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arm64 big endian boot failure with LLVM 13 and 14 after -next commit 34f66c4c4d55 #1948

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nathanchance opened this issue Oct 19, 2023 · 6 comments
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[BUG] linux-next This is an issue only seen in linux-next [FIXED][LINUX] development cycle This bug was only present and fixed in a -next or -rc cycle [FIXED][LLVM] 15 This bug was fixed in LLVM 15.x

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@nathanchance
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After commit 34f66c4c4d55 ("arm64: Use a positive cpucap for FP/SIMD") in -next, CI notices a boot failure when building with LLVM 13 and 14 (we do not test LLVM 12 and earlier because ld.lld does not support OUTPUT_FORMAT on those versions):

https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/6574588247/job/17865804560
https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/6574643887/job/17867052219

$ make -skj"$(nproc)" ARCH=arm64 LLVM=1 virtconfig

$ scripts/config -d CPU_LITTLE_ENDIAN -e CPU_BIG_ENDIAN

$ make -skj"$(nproc)" ARCH=arm64 LLVM=1 olddefconfig Image.gz

$ boot-qemu.py -k . -t 15s
...
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x000f0510]
[    0.000000] Linux version 6.6.0-rc3-00013-g34f66c4c4d55 (nathan@dev-arch.thelio-3990X) (ClangBuiltLinux clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1), ClangBuiltLinux LLD 14.0.6) #1 SMP PREEMPT Thu Oct 19 10:59:15 MST 2023
[    0.000000] KASLR enabled
[    0.000000] random: crng init done
[    0.000000] Machine model: linux,dummy-virt
[    0.000000] earlycon: pl11 at MMIO 0x0000000009000000 (options '')
[    0.000000] printk: bootconsole [pl11] enabled
[    0.000000] Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
[    0.000000] Hardware name: linux,dummy-virt (DT)
[    0.000000] pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    0.000000] pc : __pi_strcmp+0x1c/0x150
[    0.000000] lr : populate_properties+0xe4/0x254
[    0.000000] sp : ffffd014173d3ad0
[    0.000000] x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
[    0.000000] x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
[    0.000000] x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
[    0.000000] x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
[    0.000000] x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
[    0.000000] x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
[    0.000000] x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
[    0.000000] x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
[    0.000000] x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
[    0.000000] x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
[    0.000000] Kernel panic - not syncing: Unhandled exception
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
[    0.000000] Hardware name: linux,dummy-virt (DT)
[    0.000000] Call trace:
[    0.000000]  dump_backtrace+0xec/0x108
[    0.000000]  show_stack+0x18/0x2c
[    0.000000]  dump_stack_lvl+0x50/0x68
[    0.000000]  dump_stack+0x18/0x24
[    0.000000]  panic+0x13c/0x340
[    0.000000]  el1t_64_irq_handler+0x0/0x1c
[    0.000000]  el1_abort+0x0/0x5c
[    0.000000]  el1h_64_sync+0x64/0x68
[    0.000000]  __pi_strcmp+0x1c/0x150
[    0.000000]  unflatten_dt_nodes+0x1e8/0x2d8
[    0.000000]  __unflatten_device_tree+0x5c/0x15c
[    0.000000]  unflatten_device_tree+0x38/0x50
[    0.000000]  setup_arch+0x164/0x1e0
[    0.000000]  start_kernel+0x64/0x38c
[    0.000000]  __primary_switched+0xbc/0xc4
qemu-system-aarch64: terminating on signal 15 from pid 2994349 (timeout)
# bad: [4230ea146b1e64628f11e44290bb4008e391bc24] Add linux-next specific files for 20231019
# good: [dd72f9c7e512da377074d47d990564959b772643] Merge tag 'spi-fix-v6-6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
git bisect start '4230ea146b1e64628f11e44290bb4008e391bc24' 'dd72f9c7e512da377074d47d990564959b772643'
# bad: [2958944f7786b88cb86f7b3377c1a8bda75fd506] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git
git bisect bad 2958944f7786b88cb86f7b3377c1a8bda75fd506
# good: [a1fea94f1270c0b2e441320e1c0b185dd5961070] bcachefs: KEY_TYPE_error now counts towards i_sectors
git bisect good a1fea94f1270c0b2e441320e1c0b185dd5961070
# bad: [c6d5508ffd185ad82fd3458c0c9acd1801d4d123] Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-devel.git
git bisect bad c6d5508ffd185ad82fd3458c0c9acd1801d4d123
# good: [e93a66f24437a1e36275b357b718be2b270d51c7] Merge branch 'for-next' of git://git.armlinux.org.uk/~rmk/linux-arm.git
git bisect good e93a66f24437a1e36275b357b718be2b270d51c7
# good: [0a84cbfb7fedf39843e12953c61a51bc8ab38673] Merge tag 'amlogic-arm64-dt-for-v6.7' of https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux into soc/dt
git bisect good 0a84cbfb7fedf39843e12953c61a51bc8ab38673
# good: [0abc4a0457d9b04756f7df2d3334e9b0e13679d8] Merge branch 'soc/drivers' into for-next
git bisect good 0abc4a0457d9b04756f7df2d3334e9b0e13679d8
# bad: [43130e7ae2b84aa59991a995f4f5d6651cd3d4b5] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git
git bisect bad 43130e7ae2b84aa59991a995f4f5d6651cd3d4b5
# bad: [a545beb64ec48b128d863da0092917413011e91f] Merge branch 'for-next/perf' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git
git bisect bad a545beb64ec48b128d863da0092917413011e91f
# bad: [e8d4006dc24e66105444715d6d5daa244aa2bdec] arm64: Remove cpus_have_const_cap()
git bisect bad e8d4006dc24e66105444715d6d5daa244aa2bdec
# bad: [25693f1771552ad6a2f38c7749a5b7516bbddd1d] arm64: Avoid cpus_have_const_cap() for ARM64_HAS_DIT
git bisect bad 25693f1771552ad6a2f38c7749a5b7516bbddd1d
# good: [d8569fba13850bbf46a172fcee63df2130cf4ecc] arm64: kvm: Use cpus_have_final_cap() explicitly
git bisect good d8569fba13850bbf46a172fcee63df2130cf4ecc
# bad: [7f0387cf76b1d026a5f0e0386a05c4cdac3a99af] arm64: Avoid cpus_have_const_cap() for ARM64_HAS_{ADDRESS,GENERIC}_AUTH
git bisect bad 7f0387cf76b1d026a5f0e0386a05c4cdac3a99af
# good: [907722917002ed06b8f75e119b83842d5f63b15e] arm64: Use build-time assertions for cpucap ordering
git bisect good 907722917002ed06b8f75e119b83842d5f63b15e
# bad: [34f66c4c4d5518c11bfb7d10defff8f814c9f28a] arm64: Use a positive cpucap for FP/SIMD
git bisect bad 34f66c4c4d5518c11bfb7d10defff8f814c9f28a
# good: [14567ba42c5747f50584eb463ac8029f2a30e0d1] arm64: Rename SVE/SME cpu_enable functions
git bisect good 14567ba42c5747f50584eb463ac8029f2a30e0d1
# first bad commit: [34f66c4c4d5518c11bfb7d10defff8f814c9f28a] arm64: Use a positive cpucap for FP/SIMD

LLVM 15 and newer do not show this issue. I bisected the fix to llvm/llvm-project@1379b15, which certainly seems like a reasonable change to land on.

While I am not exactly sure why that arm64 commit exposes this problem, it seems like something that is worth just working around in Kconfig due to arm64 big endian being a rather exotic configuration:

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b10515c0200b..cacc67121adb 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1355,6 +1355,8 @@ choice
 config CPU_BIG_ENDIAN
        bool "Build big-endian kernel"
        depends on !LD_IS_LLD || LLD_VERSION >= 130000
+       # https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c
+       depends on AS_IS_GNU || AS_VERSION >= 150000
        help
          Say Y if you plan on running a kernel with a big-endian userspace.
@nathanchance nathanchance added [PATCH] Exists There is a patch that fixes this issue [BUG] linux-next This is an issue only seen in linux-next [FIXED][LLVM] 15 This bug was fixed in LLVM 15.x labels Oct 19, 2023
@JustinStitt
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Where's the patch?

Not seeing anything recent here: https://lore.kernel.org/all/?q=dfn%3Aarch%2Farm64%2FKconfig

@nathanchance
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Where's the patch?

The diff at the end of my first post.

@JustinStitt
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Where's the patch?

The diff at the end of my first post.

Ah, right. I forgot the distinction between [PATCH] Exists and [PATCH] Submitted.

@nathanchance
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intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this issue Oct 25, 2023
A recent refactoring in the arm64 tree exposed an assembler bug in LLVM
with regards to the generation of NOPs for arm64 big endian, resulting
in near-immediate crashes on boot in QEMU.

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
@nathanchance nathanchance removed the [PATCH] Exists There is a patch that fixes this issue label Oct 25, 2023
@nickdesaulniers
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@nickdesaulniers nickdesaulniers added the [PATCH] Accepted A submitted patch has been accepted upstream label Oct 26, 2023
nathanchance added a commit to nathanchance/continuous-integration2 that referenced this issue Oct 26, 2023
LLVM's integrated assembler incorrect generates the encoding for nop
when targeting arm64 big endian. This was fixed in LLVM 15, so disable
builds for LLVM 13 and 14.

Link: ClangBuiltLinux/linux#1948
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
akiyks pushed a commit to akiyks/linux that referenced this issue Oct 27, 2023
Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
@nathanchance nathanchance added [FIXED][LINUX] development cycle This bug was only present and fixed in a -next or -rc cycle and removed [PATCH] Accepted A submitted patch has been accepted upstream labels Oct 31, 2023
@nathanchance
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While this is technically a long outstanding issue, it is not visibly problematic until the upcoming arm64 changes in 6.7, so I am closing this up now that the workaround change is in -next. It will go back to stable automatically.

mj22226 pushed a commit to mj22226/linux that referenced this issue Nov 24, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mj22226 pushed a commit to mj22226/linux that referenced this issue Nov 26, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kaz205 pushed a commit to Kaz205/linux that referenced this issue Nov 26, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kaz205 pushed a commit to Kaz205/linux that referenced this issue Nov 27, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mj22226 pushed a commit to mj22226/linux that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
woodsts pushed a commit to woodsts/linux-stable that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Whissi pushed a commit to Whissi/linux-stable that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sj-aws pushed a commit to amazonlinux/linux that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Whissi pushed a commit to Whissi/linux-stable that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Whissi pushed a commit to Whissi/linux-stable that referenced this issue Nov 28, 2023
commit 146a15b upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SkrilaxCZ pushed a commit to SkrilaxCZ/l4t-kernel that referenced this issue Dec 1, 2023
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sparkstar pushed a commit to sparkstar/jammy-stable that referenced this issue Jan 22, 2024
BugLink: https://bugs.launchpad.net/bugs/2050038

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
sparkstar pushed a commit to sparkstar/jammy-stable that referenced this issue Jan 23, 2024
BugLink: https://bugs.launchpad.net/bugs/2050038

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
sparkstar pushed a commit to sparkstar/jammy-stable that referenced this issue Jan 25, 2024
BugLink: https://bugs.launchpad.net/bugs/2050038

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
sileshn pushed a commit to sileshn/ubuntu-kernel-jammy that referenced this issue Feb 4, 2024
BugLink: https://bugs.launchpad.net/bugs/2050038

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Shakib-BD pushed a commit to Shakib-BD/kernel_xiaomi-yunluo that referenced this issue Mar 23, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: شَکِیْب | Shakib <its.shakib@proton.me>
wanghao75 pushed a commit to openeuler-mirror/kernel that referenced this issue Apr 16, 2024
stable inclusion
from stable-v5.10.202
commit d08a1e75253b4e19ae290b1c35349f12cfcebc0a
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9DZOS

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d08a1e75253b4e19ae290b1c35349f12cfcebc0a

--------------------------------

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>
xt0032rus pushed a commit to xt0032rus/android_kernel_xiaomi_sm8550 that referenced this issue May 3, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: xt0032rus <andrey.denikin9@mail.com>
steadfasterX pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue May 27, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
steadfasterX pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue May 27, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 1, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 1, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 1, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 2, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 4, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 4, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wanghao75 pushed a commit to openeuler-mirror/kernel that referenced this issue Jun 4, 2024
stable inclusion
from stable-v5.10.202
commit d08a1e75253b4e19ae290b1c35349f12cfcebc0a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9R4L4
CVE: CVE-2023-52750

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d08a1e75253b4e19ae290b1c35349f12cfcebc0a

--------------------------------

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Conflicts:
	arch/arm64/Kconfig
[lhb: adjust context]
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
wanghao75 pushed a commit to openeuler-mirror/kernel that referenced this issue Jun 4, 2024
stable inclusion
from stable-v5.10.202
commit d08a1e75253b4e19ae290b1c35349f12cfcebc0a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9R4L4
CVE: CVE-2023-52750

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d08a1e75253b4e19ae290b1c35349f12cfcebc0a

--------------------------------

commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 17, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 19, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 20, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 21, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 21, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 21, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 21, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 24, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jun 24, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jul 15, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jul 16, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jul 16, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sfX-bot pushed a commit to AXP-OS/android_kernel_google_gs201 that referenced this issue Jul 17, 2024
commit 146a15b873353f8ac28dc281c139ff611a3c4848 upstream.

Prior to LLVM 15.0.0, LLVM's integrated assembler would incorrectly
byte-swap NOP when compiling for big-endian, and the resulting series of
bytes happened to match the encoding of FNMADD S21, S30, S0, S0.

This went unnoticed until commit:

  34f66c4c4d5518c1 ("arm64: Use a positive cpucap for FP/SIMD")

Prior to that commit, the kernel would always enable the use of FPSIMD
early in boot when __cpu_setup() initialized CPACR_EL1, and so usage of
FNMADD within the kernel was not detected, but could result in the
corruption of user or kernel FPSIMD state.

After that commit, the instructions happen to trap during boot prior to
FPSIMD being detected and enabled, e.g.

| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x000000001fe00000 -- ASIMD
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| pstate: 400000c9 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
| pc : __pi_strcmp+0x1c/0x150
| lr : populate_properties+0xe4/0x254
| sp : ffffd014173d3ad0
| x29: ffffd014173d3af0 x28: fffffbfffddffcb8 x27: 0000000000000000
| x26: 0000000000000058 x25: fffffbfffddfe054 x24: 0000000000000008
| x23: fffffbfffddfe000 x22: fffffbfffddfe000 x21: fffffbfffddfe044
| x20: ffffd014173d3b70 x19: 0000000000000001 x18: 0000000000000005
| x17: 0000000000000010 x16: 0000000000000000 x15: 00000000413e7000
| x14: 0000000000000000 x13: 0000000000001bcc x12: 0000000000000000
| x11: 00000000d00dfeed x10: ffffd414193f2cd0 x9 : 0000000000000000
| x8 : 0101010101010101 x7 : ffffffffffffffc0 x6 : 0000000000000000
| x5 : 0000000000000000 x4 : 0101010101010101 x3 : 000000000000002a
| x2 : 0000000000000001 x1 : ffffd014171f2988 x0 : fffffbfffddffcb8
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc3-00013-g34f66c4c4d55 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0xec/0x108
|  show_stack+0x18/0x2c
|  dump_stack_lvl+0x50/0x68
|  dump_stack+0x18/0x24
|  panic+0x13c/0x340
|  el1t_64_irq_handler+0x0/0x1c
|  el1_abort+0x0/0x5c
|  el1h_64_sync+0x64/0x68
|  __pi_strcmp+0x1c/0x150
|  unflatten_dt_nodes+0x1e8/0x2d8
|  __unflatten_device_tree+0x5c/0x15c
|  unflatten_device_tree+0x38/0x50
|  setup_arch+0x164/0x1e0
|  start_kernel+0x64/0x38c
|  __primary_switched+0xbc/0xc4

Restrict CONFIG_CPU_BIG_ENDIAN to a known good assembler, which is
either GNU as or LLVM's IAS 15.0.0 and newer, which contains the linked
commit.

Closes: ClangBuiltLinux/linux#1948
Link: llvm/llvm-project@1379b15
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231025-disable-arm64-be-ias-b4-llvm-15-v1-1-b25263ed8b23@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[BUG] linux-next This is an issue only seen in linux-next [FIXED][LINUX] development cycle This bug was only present and fixed in a -next or -rc cycle [FIXED][LLVM] 15 This bug was fixed in LLVM 15.x
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