Mark-Rutland/t…
Commits on Nov 17, 2021
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Ingo Molnar <mingo@redhat.com>
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powerpc: snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org>
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powerpc: avoid discarding flags in system_call_exception()
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Thus, when setting flags we must use an atomic operation rather than a plain read-modify-write sequence, as a plain read-modify-write may discard flags which are concurrently set by a remote thread, e.g. // task A // task B tmp = A->thread_info.flags; set_tsk_thread_flag(A, NEWFLAG_B); tmp |= NEWFLAG_A; A->thread_info.flags = tmp; In arch/powerpc/kernel/interrupt.c's system_call_exception(), we set _TIF_RESTOREALL in the thread info flags with a read-modify-write, which may result in other flags being discarded. Elsewhere in the file we use clear_bits() to atomically remove flag bits, so let's use set_bits() here for consistency with those. I presume there may be reasons (e.g. instrumentation) that prevent the use of set_thread_flag() and clear_thread_flag() here, which would otherwise be preferable. Fixes: ae7aaec ("powerpc/64s: system call rfscv workaround for TM bugs") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Eirik Fuller <efuller@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com>
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openrisc: snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Stafford Horne <shorne@gmail.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
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microblaze: snapshot thread flags
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Tested-by: Michal Simek <michal.simek@xilinx.com>
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com>
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Russell King <linux@armlinux.org.uk>
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Richard Henderson <rth@twiddle.net>
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. The READ_ONCE(ti->flags) .. cmpxchg(ti->flags) loop in set_nr_if_polling() is left as-is for clarity. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vincent Guittot <vincent.guittot@linaro.org>
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Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not. Convert them all to the new flag accessor helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de>
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thread_info: add helpers to snapshot thread flags
In <linux/thread_info.h> there are helpers to manipulate individual thread flags, but where code wants to check several flags at once, it must open code reading current_thread_info()->flags and operating on a snapshot. As some flags can be set remotely it's necessary to use READ_ONCE() to get a consistent snapshot even when IRQs are disabled, but some code forgets to do this. Generally this is unlike to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race. To make it easier to do the right thing, and to highlight that concurrent modification is possible, add new helpers to snapshot the flags, which should be used in preference to plain reads. Subsequent patches will move existing code to use the new helpers. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marco Elver <elver@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org>
Commits on Nov 8, 2021
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arm64: pgtable: make __pte_to_phys/__phys_to_pte_val inline functions
gcc warns about undefined behavior the vmalloc code when building with CONFIG_ARM64_PA_BITS_52, when the 'idx++' in the argument to __phys_to_pte_val() is evaluated twice: mm/vmalloc.c: In function 'vmap_pfn_apply': mm/vmalloc.c:2800:58: error: operation on 'data->idx' may be undefined [-Werror=sequence-point] 2800 | *pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot)); | ~~~~~~~~~^~ arch/arm64/include/asm/pgtable-types.h:25:37: note: in definition of macro '__pte' 25 | #define __pte(x) ((pte_t) { (x) } ) | ^ arch/arm64/include/asm/pgtable.h:80:15: note: in expansion of macro '__phys_to_pte_val' 80 | __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) | ^~~~~~~~~~~~~~~~~ mm/vmalloc.c:2800:30: note: in expansion of macro 'pfn_pte' 2800 | *pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot)); | ^~~~~~~ I have no idea why this never showed up earlier, but the safest workaround appears to be changing those macros into inline functions so the arguments get evaluated only once. Cc: Matthew Wilcox <willy@infradead.org> Fixes: 75387b9 ("arm64: handle 52-bit physical addresses in page table entries") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20211105075414.2553155-1-arnd@kernel.org Signed-off-by: Will Deacon <will@kernel.org> -
arm64: Track no early_pgtable_alloc() for kmemleak
After switched page size from 64KB to 4KB on several arm64 servers here, kmemleak starts to run out of early memory pool due to a huge number of those early_pgtable_alloc() calls: kmemleak_alloc_phys() memblock_alloc_range_nid() memblock_phys_alloc_range() early_pgtable_alloc() init_pmd() alloc_init_pud() __create_pgd_mapping() __map_memblock() paging_init() setup_arch() start_kernel() Increased the default value of DEBUG_KMEMLEAK_MEM_POOL_SIZE by 4 times won't be enough for a server with 200GB+ memory. There isn't much interesting to check memory leaks for those early page tables and those early memory mappings should not reference to other memory. Hence, no kmemleak false positives, and we can safely skip tracking those early allocations from kmemleak like we did in the commit fed84c7 ("mm/memblock.c: skip kmemleak for kasan_init()") without needing to introduce complications to automatically scale the value depends on the runtime memory size etc. After the patch, the default value of DEBUG_KMEMLEAK_MEM_POOL_SIZE becomes sufficient again. Signed-off-by: Qian Cai <quic_qiancai@quicinc.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/r/20211105150509.7826-1-quic_qiancai@quicinc.com Signed-off-by: Will Deacon <will@kernel.org>
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arm64: mte: change PR_MTE_TCF_NONE back into an unsigned long
This constant was previously an unsigned long, but was changed into an int in commit 433c38f ("arm64: mte: change ASYNC and SYNC TCF settings into bitfields"). This ended up causing spurious unsigned-signed comparison warnings in expressions such as: (x & PR_MTE_TCF_MASK) != PR_MTE_TCF_NONE Therefore, change it back into an unsigned long to silence these warnings. Link: https://linux-review.googlesource.com/id/I07a72310db30227a5b7d789d0b817d78b657c639 Signed-off-by: Peter Collingbourne <pcc@google.com> Link: https://lore.kernel.org/r/20211105230829.2254790-1-pcc@google.com Signed-off-by: Will Deacon <will@kernel.org>
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arm64: vdso: remove -nostdlib compiler flag
The -nostdlib option requests the compiler to not use the standard system startup files or libraries when linking. It is effective only when $(CC) is used as a linker driver. Since commit 691efbe ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO"), $(LD) is directly used, hence -nostdlib is unneeded. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20211107161802.323125-1-masahiroy@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
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arm64: arm64_ftr_reg->name may not be a human-readable string
The id argument of ARM64_FTR_REG_OVERRIDE() is used for two purposes: one as the system register encoding (used for the sys_id field of __ftr_reg_entry), and the other as the register name (stringified and used for the name field of arm64_ftr_reg), which is debug information. The id argument is supposed to be a macro that indicates an encoding of the register (eg. SYS_ID_AA64PFR0_EL1, etc). ARM64_FTR_REG(), which also has the same id argument, uses ARM64_FTR_REG_OVERRIDE() and passes the id to the macro. Since the id argument is completely macro-expanded before it is substituted into a macro body of ARM64_FTR_REG_OVERRIDE(), the stringified id in the body of ARM64_FTR_REG_OVERRIDE is not a human-readable register name, but a string of numeric bitwise operations. Fix this so that human-readable register names are available as debug information. Fixes: 8f266a5 ("arm64: cpufeature: Add global feature override facility") Signed-off-by: Reiji Watanabe <reijiw@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211101045421.2215822-1-reijiw@google.com Signed-off-by: Will Deacon <will@kernel.org>
Commits on Oct 29, 2021
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Merge branch 'for-next/fixes' into for-next/core
Merge for-next/fixes to resolve conflicts in arm64_hugetlb_cma_reserve(). * for-next/fixes: acpi/arm64: fix next_platform_timer() section mismatch error arm64/hugetlb: fix CMA gigantic page order for non-4K PAGE_SIZE
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Merge branch 'for-next/vdso' into for-next/core
* for-next/vdso: arm64: vdso32: require CROSS_COMPILE_COMPAT for gcc+bfd arm64: vdso32: suppress error message for 'make mrproper' arm64: vdso32: drop test for -march=armv8-a arm64: vdso32: drop the test for dmb ishld
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Merge branch 'for-next/trbe-errata' into for-next/core
* for-next/trbe-errata: arm64: errata: Add detection for TRBE write to out-of-range arm64: errata: Add workaround for TSB flush failures arm64: errata: Add detection for TRBE overwrite in FILL mode arm64: Add Neoverse-N2, Cortex-A710 CPU part definition
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Merge branch 'for-next/sve' into for-next/core
* for-next/sve: arm64/sve: Fix warnings when SVE is disabled arm64/sve: Add stub for sve_max_virtualisable_vl() arm64/sve: Track vector lengths for tasks in an array arm64/sve: Explicitly load vector length when restoring SVE state arm64/sve: Put system wide vector length information into structs arm64/sve: Use accessor functions for vector lengths in thread_struct arm64/sve: Rename find_supported_vector_length() arm64/sve: Make access to FFR optional arm64/sve: Make sve_state_size() static arm64/sve: Remove sve_load_from_fpsimd_state() arm64/fp: Reindent fpsimd_save()
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Merge branch 'for-next/scs' into for-next/core
* for-next/scs: scs: Release kasan vmalloc poison in scs_free process
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Merge branch 'for-next/pfn-valid' into for-next/core
* for-next/pfn-valid: arm64/mm: drop HAVE_ARCH_PFN_VALID dma-mapping: remove bogus test for pfn_valid from dma_map_resource
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Merge branch 'for-next/perf' into for-next/core
* for-next/perf: drivers/perf: Improve build test coverage drivers/perf: thunderx2_pmu: Change data in size tx2_uncore_event_update() drivers/perf: hisi: Fix PA PMU counter offset
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Merge branch 'for-next/mte' into for-next/core
* for-next/mte: kasan: Extend KASAN mode kernel parameter arm64: mte: Add asymmetric mode support arm64: mte: CPU feature detection for Asymm MTE arm64: mte: Bitfield definitions for Asymm MTE kasan: Remove duplicate of kasan_flag_async arm64: kasan: mte: move GCR_EL1 switch to task switch when KASAN disabled
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Merge branch 'for-next/mm' into for-next/core
* for-next/mm: arm64: mm: update max_pfn after memory hotplug arm64/mm: Add pud_sect_supported() arm64: mm: Drop pointless call to set_max_mapnr()
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Merge branch 'for-next/misc' into for-next/core
* for-next/misc: arm64: Select POSIX_CPU_TIMERS_TASK_WORK arm64: Document boot requirements for FEAT_SME_FA64 arm64: ftrace: use function_nocfi for _mcount as well arm64: asm: setup.h: export common variables arm64/traps: Avoid unnecessary kernel/user pointer conversion
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Merge branch 'for-next/kselftest' into for-next/core
* for-next/kselftest: selftests: arm64: Factor out utility functions for assembly FP tests selftests: arm64: Add coverage of ptrace flags for SVE VL inheritance selftests: arm64: Verify that all possible vector lengths are handled selftests: arm64: Fix and enable test for setting current VL in vec-syscfg selftests: arm64: Remove bogus error check on writing to files selftests: arm64: Fix printf() format mismatch in vec-syscfg selftests: arm64: Move FPSIMD in SVE ptrace test into a function selftests: arm64: More comprehensively test the SVE ptrace interface selftests: arm64: Verify interoperation of SVE and FPSIMD register sets selftests: arm64: Clarify output when verifying SVE register set selftests: arm64: Document what the SVE ptrace test is doing selftests: arm64: Remove extraneous register setting code selftests: arm64: Don't log child creation as a test in SVE ptrace test selftests: arm64: Use a define for the number of SVE ptrace tests to be run
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Merge branch 'for-next/kexec' into for-next/core
* for-next/kexec: arm64: trans_pgd: remove trans_pgd_map_page() arm64: kexec: remove cpu-reset.h arm64: kexec: remove the pre-kexec PoC maintenance arm64: kexec: keep MMU enabled during kexec relocation arm64: kexec: install a copy of the linear-map arm64: kexec: use ld script for relocation function arm64: kexec: relocate in EL1 mode arm64: kexec: configure EL2 vectors for kexec arm64: kexec: pass kimage as the only argument to relocation function arm64: kexec: Use dcache ops macros instead of open-coding arm64: kexec: skip relocation code for inplace kexec arm64: kexec: flush image and lists during kexec load time arm64: hibernate: abstract ttrb0 setup function arm64: trans_pgd: hibernate: Add trans_pgd_copy_el2_vectors arm64: kernel: add helper for booted at EL2 and not VHE
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Merge branch 'for-next/extable' into for-next/core
* for-next/extable: arm64: vmlinux.lds.S: remove `.fixup` section arm64: extable: add load_unaligned_zeropad() handler arm64: extable: add a dedicated uaccess handler arm64: extable: add `type` and `data` fields arm64: extable: use `ex` for `exception_table_entry` arm64: extable: make fixup_exception() return bool arm64: extable: consolidate definitions arm64: gpr-num: support W registers arm64: factor out GPR numbering helpers arm64: kvm: use kvm_exception_table_entry arm64: lib: __arch_copy_to_user(): fold fixups into body arm64: lib: __arch_copy_from_user(): fold fixups into body arm64: lib: __arch_clear_user(): fold fixups into body
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Merge branch 'for-next/8.6-timers' into for-next/core
* for-next/8.6-timers: arm64: Add HWCAP for self-synchronising virtual counter arm64: Add handling of CNTVCTSS traps arm64: Add CNT{P,V}CTSS_EL0 alternatives to cnt{p,v}ct_el0 arm64: Add a capability for FEAT_ECV clocksource/drivers/arch_arm_timer: Move workaround synchronisation around clocksource/drivers/arm_arch_timer: Fix masking for high freq counters clocksource/drivers/arm_arch_timer: Drop unnecessary ISB on CVAL programming clocksource/drivers/arm_arch_timer: Remove any trace of the TVAL programming interface clocksource/drivers/arm_arch_timer: Work around broken CVAL implementations clocksource/drivers/arm_arch_timer: Advertise 56bit timer to the core code clocksource/drivers/arm_arch_timer: Move MMIO timer programming over to CVAL clocksource/drivers/arm_arch_timer: Fix MMIO base address vs callback ordering issue clocksource/drivers/arm_arch_timer: Move drop _tval from erratum function names clocksource/drivers/arm_arch_timer: Move system register timer programming over to CVAL clocksource/drivers/arm_arch_timer: Extend write side of timer register accessors to u64 clocksource/drivers/arm_arch_timer: Drop CNT*_TVAL read accessors clocksource/arm_arch_timer: Add build-time guards for unhandled register accesses
Commits on Oct 28, 2021
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arm64: Select POSIX_CPU_TIMERS_TASK_WORK
With 6caa581 ("KVM: arm64: Use generic KVM xfer to guest work function") all arm64 exit paths are properly equipped to handle the POSIX timers' task work. Deferring timer callbacks to thread context, not only limits the amount of time spent in hard interrupt context, but is a safer implementation[1], and will allow PREEMPT_RT setups to use KVM[2]. So let's enable POSIX_CPU_TIMERS_TASK_WORK on arm64. [1] https://lore.kernel.org/all/20200716201923.228696399@linutronix.de/ [2] https://lore.kernel.org/linux-rt-users/87v92bdnlx.ffs@tglx/ Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211018144713.873464-1-nsaenzju@redhat.com Signed-off-by: Will Deacon <will@kernel.org>
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arm64: Document boot requirements for FEAT_SME_FA64
The EAC1 release of the SME specification adds the FA64 feature which requires enablement at higher ELs before lower ELs can use it. Document what we require from higher ELs in our boot requirements. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20211026111802.12853-1-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
Commits on Oct 26, 2021
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arm64/sve: Fix warnings when SVE is disabled
In configurations where SVE is disabled we define but never reference the functions for retrieving the default vector length, causing warnings. Fix this by move the ifdef up, marking get_default_vl() inline since it is referenced from code guarded by an IS_ENABLED() check, and do the same for the other accessors for consistency. Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20211022141635.2360415-3-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
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arm64/sve: Add stub for sve_max_virtualisable_vl()
Fixes build problems for configurations with KVM enabled but SVE disabled. Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20211022141635.2360415-2-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
Commits on Oct 21, 2021
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arm64: errata: Add detection for TRBE write to out-of-range
Arm Neoverse-N2 and Cortex-A710 cores are affected by an erratum where the trbe, under some circumstances, might write upto 64bytes to an address after the Limit as programmed by the TRBLIMITR_EL1.LIMIT. This might - - Corrupt a page in the ring buffer, which may corrupt trace from a previous session, consumed by userspace. - Hit the guard page at the end of the vmalloc area and raise a fault. To keep the handling simpler, we always leave the last page from the range, which TRBE is allowed to write. This can be achieved by ensuring that we always have more than a PAGE worth space in the range, while calculating the LIMIT for TRBE. And then the LIMIT pointer can be adjusted to leave the PAGE (TRBLIMITR.LIMIT -= PAGE_SIZE), out of the TRBE range while enabling it. This makes sure that the TRBE will only write to an area within its allowed limit (i.e, [head-head+size]) and we do not have to handle address faults within the driver. Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20211019163153.3692640-5-suzuki.poulose@arm.com Signed-off-by: Will Deacon <will@kernel.org>