The usage of get_cpu_var() in zs_map_object() is problematic because
it disables preemption and makes it impossible to acquire any sleeping
lock on PREEMPT_RT such as a spinlock_t.
Replace the get_cpu_var() usage with a local_lock_t which is embedded
struct mapping_area. It ensures that the access the struct is
synchronized against all users on the same CPU.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[minchan: remove the bit_spin_lock part and change the title]
Signed-off-by: Minchan Kim <minchan@kernel.org>

The zsmalloc has used a bit for spin_lock in zpage handle to keep
zpage object alive during several operations. However, it causes
the problem for PREEMPT_RT as well as introducing too complicated.

This patch replaces the bit spin_lock with pool->migrate_lock
rwlock. It could make the code simple as well as zsmalloc work
under PREEMPT_RT.

The drawback is the pool->migrate_lock is bigger granuarity than
per zpage lock so the contention would be higher than old when
both IO-related operations(i.e., zsmalloc, zsfree, zs_[map|unmap])
and compaction(page/zpage migration) are going in parallel(*,
the migrate_lock is rwlock and IO related functions are all read
side lock so there is no contention). However, the write-side
is fast enough(dominant overhead is just page copy) so it wouldn't
affect much. If the lock granurity becomes more problem later,
we could introduce table locks based on handle as a hash value.

Signed-off-by: Minchan Kim <minchan@kernel.org>

zspage isolation for migration introduced additional exceptions
to be dealt with since the zspage was isolated from class list.
The reason why I isolated zspage from class list was to prevent
race between obj_malloc and page migration via allocating zpage
from the zspage further. However, it couldn't prevent object
freeing from zspage so it needed corner case handling.

This patch removes the whole mess. Now, we are fine since
class->lock and zspage->lock can prevent the race.

Signed-off-by: Minchan Kim <minchan@kernel.org>

the flag aims for zspage, not per page. Let's move it to zspage.

Signed-off-by: Minchan Kim <minchan@kernel.org>

The usage pattern for obj_to_head is to check whether the zpage
is allocated or not. Thus, introduce obj_allocated.

Signed-off-by: Minchan Kim <minchan@kernel.org>

This patch moves class stat update out of obj_malloc since
it's not related to zspage operation.
This is a preparation to introduce new lock scheme in next
patch.

Signed-off-by: Minchan Kim <minchan@kernel.org>

The stat aims for class stat, not zspage so rename it.

Signed-off-by: Minchan Kim <minchan@google.com>

get_zspage_mapping returns fullness as well as class_idx. However,
the fullness is usually not used since it could be stale in some
contexts. It causes misleading as well as unnecessary instructions
so this patch introduces zspage_class.

obj_to_location also produces page and index but we don't need
always the index, either so this patch introduces obj_to_page.

Signed-off-by: Minchan Kim <minchan@kernel.org>

….org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fix compilation of callchain related code on powerpc with gcc11+

 - Fix PERF_SAMPLE_WEIGHT_STRUCT support in 'perf script'

 - Check session->header.env.arch before using it, fixing a segmentation
   fault

 - Suppress 'rm dlfilter' build messages

* tag 'perf-tools-fixes-for-v5.15-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf script: Fix PERF_SAMPLE_WEIGHT_STRUCT support
  perf callchain: Fix compilation on powerpc with gcc11+
  perf script: Check session->header.env.arch before using it
  perf build: Suppress 'rm dlfilter' build message

Pull kvm fixes from Paolo Bonzini:

 - Fixes for s390 interrupt delivery

 - Fixes for Xen emulator bugs showing up as debug kernel WARNs

 - Fix another issue with SEV/ES string I/O VMGEXITs

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Take srcu lock in post_kvm_run_save()
  KVM: SEV-ES: fix another issue with string I/O VMGEXITs
  KVM: x86/xen: Fix kvm_xen_has_interrupt() sleeping in kvm_vcpu_block()
  KVM: x86: switch pvclock_gtod_sync_lock to a raw spinlock
  KVM: s390: preserve deliverable_mask in __airqs_kick_single_vcpu
  KVM: s390: clear kicked_mask before sleeping again

-F weight in perf script is broken.

  # ./perf mem record
  # ./perf script -F weight
  Samples for 'dummy:HG' event do not have WEIGHT attribute set. Cannot
print 'weight' field.

The sample type, PERF_SAMPLE_WEIGHT_STRUCT, is an alternative of the
PERF_SAMPLE_WEIGHT sample type. They share the same space, weight. The
lower 32 bits are exactly the same for both sample type. The higher 32
bits may be different for different architecture. For a new kernel on
x86, the PERF_SAMPLE_WEIGHT_STRUCT is used. For an old kernel or other
ARCHs, the PERF_SAMPLE_WEIGHT is used.

With -F weight, current perf script will only check the input string
"weight" with the PERF_SAMPLE_WEIGHT sample type. Because the commit
ea8d0ed ("perf tools: Support PERF_SAMPLE_WEIGHT_STRUCT") didn't
update the PERF_SAMPLE_WEIGHT_STRUCT sample type for perf script. For a
new kernel on x86, the check fails.

Use PERF_SAMPLE_WEIGHT_TYPE, which supports both sample types, to
replace PERF_SAMPLE_WEIGHT

Fixes: ea8d0ed ("perf tools: Support PERF_SAMPLE_WEIGHT_STRUCT")
Reported-by: Joe Mario <jmario@redhat.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Joe Mario <jmario@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Joe Mario <jmario@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: https://lore.kernel.org/r/1632929894-102778-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Got following build fail on powerpc:

    CC      arch/powerpc/util/skip-callchain-idx.o
  In function ‘check_return_reg’,
      inlined from ‘check_return_addr’ at arch/powerpc/util/skip-callchain-idx.c:213:7,
      inlined from ‘arch_skip_callchain_idx’ at arch/powerpc/util/skip-callchain-idx.c:265:7:
  arch/powerpc/util/skip-callchain-idx.c:54:18: error: ‘dwarf_frame_register’ accessing 96 bytes \
  in a region of size 64 [-Werror=stringop-overflow=]
     54 |         result = dwarf_frame_register(frame, ra_regno, ops_mem, &ops, &nops);
        |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  arch/powerpc/util/skip-callchain-idx.c: In function ‘arch_skip_callchain_idx’:
  arch/powerpc/util/skip-callchain-idx.c:54:18: note: referencing argument 3 of type ‘Dwarf_Op *’
  In file included from /usr/include/elfutils/libdwfl.h:32,
                   from arch/powerpc/util/skip-callchain-idx.c:10:
  /usr/include/elfutils/libdw.h:1069:12: note: in a call to function ‘dwarf_frame_register’
   1069 | extern int dwarf_frame_register (Dwarf_Frame *frame, int regno,
        |            ^~~~~~~~~~~~~~~~~~~~
  cc1: all warnings being treated as errors

The dwarf_frame_register args changed with [1],
Updating ops_mem accordingly.

[1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=5621fe5443da23112170235dd5cac161e5c75e65

Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Mark Wieelard <mjw@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20210928195253.1267023-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When perf.data is not written cleanly, we would like to process existing
data as much as possible (please see f_header.data.size == 0 condition
in perf_session__read_header). However, perf.data with partial data may
crash perf. Specifically, we see crash in 'perf script' for NULL
session->header.env.arch.

Fix this by checking session->header.env.arch before using it to determine
native_arch. Also split the if condition so it is easier to read.

Committer notes:

If it is a pipe, we already assume is a native arch, so no need to check
session->header.env.arch.

Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211004053238.514936-1-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The following build message:

	rm dlfilters/dlfilter-test-api-v0.o

is unwanted.

The object file is being treated as an intermediate file and being
automatically removed. Mark the object file as .SECONDARY to prevent
removal and hence the message.

Requested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20210930062849.110416-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

…it/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Three small fixes, all in drivers, and one sizeable update to the UFS
  driver to remove the HPB 2.0 feature that has been objected to by Jens
  and Christoph.

  Although the UFS patch is large and last minute, it's essentially the
  least intrusive way of resolving the objections in time for the 5.15
  release"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: ufshpb: Remove HPB2.0 flows
  scsi: mpt3sas: Fix reference tag handling for WRITE_INSERT
  scsi: ufs: ufs-exynos: Correct timeout value setting registers
  scsi: ibmvfc: Fix up duplicate response detection

…/kernel/git/clk/linux

Pull clk fix from Stephen Boyd:
 "One fix for the composite clk that broke when we changed this clk type
  to use the determine_rate instead of round_rate clk op by default.
  This caused lots of problems on Rockchip SoCs because they heavily use
  the composite clk code to model the clk tree"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: composite: Also consider .determine_rate for rate + mux composites

…linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:
 "These are pretty late, but they do fix concrete issues.

   - ensure the trap vector's address is aligned.

   - avoid re-populating the KASAN shadow memory.

   - allow kasan to build without warnings, which have recently become
     errors"

* tag 'riscv-for-linus-5.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Fix asan-stack clang build
  riscv: Do not re-populate shadow memory with kasan_populate_early_shadow
  riscv: fix misalgned trap vector base address

The Host Performance Buffer feature allows UFS read commands to carry the
physical media addresses along with the LBAs, thus allowing less internal
L2P-table switches in the device.  HPB1.0 allowed a single LBA, while
HPB2.0 increases this capacity up to 255 blocks.

Carrying more than a single record, the read operation is no longer purely
of type "read" but a "hybrid" command: Writing the physical address to the
device in one operation and reading back the required payload in another.

The JEDEC HPB spec defines two commands for this operation:
HPB-WRITE-BUFFER (0x2) to write the physical addresses to device, and
HPB-READ to read the payload.

With the current HPB design the UFS driver has no alternative but to divide
the READ request into 2 separate commands: HPB-WRITE-BUFFER and HPB-READ.
This causes a great deal of aggravation to the block layer guys who
demanded that we completely revert the entire HPB driver regardless of the
huge amount of corporate effort already invested in it.

As a compromise, remove only the pieces that implement the 2.0
specification. This is done as a matter of urgency for the final 5.15
release.

Link: https://lore.kernel.org/r/20211030062301.248-1-avri.altman@wdc.com
Tested-by: Avri Altman <avri.altman@wdc.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Co-developed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

…el/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Three commits fixing some issues introduced with the recent IOMMU
  changes we merged.

  Thanks to Alexey Kardashevskiy"

* tag 'powerpc-5.15-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries/iommu: Create huge DMA window if no MMIO32 is present
  powerpc/pseries/iommu: Check if the default window in use before removing it
  powerpc/pseries/iommu: Use correct vfree for it_map

…x/kernel/git/brgl/linux

Pull gpio fixes from Bartosz Golaszewski:

 - fix the return value check when parsing the ngpios property in
   gpio-xgs-iproc

 - check the return value of bgpio_init() in gpio-mlxbf2

* tag 'gpio-fixes-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio: mlxbf2.c: Add check for bgpio_init failure
  gpio: xgs-iproc: fix parsing of ngpios property

Pull block fixes from Jens Axboe:

 - NVMe pull request:
      - fix nvmet-tcp header digest verification (Amit Engel)
      - fix a memory leak in nvmet-tcp when releasing a queue (Maurizio
        Lombardi)
      - fix nvme-tcp H2CData PDU send accounting again (Sagi Grimberg)
      - fix digest pointer calculation in nvme-tcp and nvmet-tcp (Varun
        Prakash)
      - fix possible nvme-tcp req->offset corruption (Varun Prakash)

 - Queue drain ordering fix (Ming)

 - Partition check regression for zoned devices (Shin'ichiro)

 - Zone queue restart fix (Naohiro)

* tag 'block-5.15-2021-10-29' of git://git.kernel.dk/linux-block:
  block: Fix partition check for host-aware zoned block devices
  nvmet-tcp: fix header digest verification
  nvmet-tcp: fix data digest pointer calculation
  nvme-tcp: fix data digest pointer calculation
  nvme-tcp: fix possible req->offset corruption
  block: schedule queue restart after BLK_STS_ZONE_RESOURCE
  block: drain queue after disk is removed from sysfs
  nvme-tcp: fix H2CData PDU send accounting (again)
  nvmet-tcp: fix a memory leak when releasing a queue

Testing revealed a problem with how the reference tag was handled for
a WRITE_INSERT operation. The SCSI_PROT_REF_CHECK flag is not set when
the controller is asked to generate the protection information
(i.e. not DIX). And as a result the initial reference tag would not be
set in the WRITE_INSERT case.

Separate handling of the REF_CHECK and REF_INCREMENT flags to align
with both the DIX spec and the MPI implementation.

Link: https://lore.kernel.org/r/20211028034202.24225-1-martin.petersen@oracle.com
Fixes: b3e2c72 ("scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

…l/git/ulfh/mmc

Pull MMC fixes from Ulf Hansson:

 - tmio: Re-enable card irqs after a reset

 - mtk-sd: Fixup probing of cqhci for crypto

 - cqhci: Fix support for suspend/resume

 - vub300: Fix control-message timeouts

 - dw_mmc-exynos: Fix support for tuning

 - winbond: Silences build errors on M68K

 - sdhci-esdhc-imx: Fix support for tuning

 - sdhci-pci: Read card detect from ACPI for Intel Merrifield

 - sdhci: Fix eMMC support for Thundercomm TurboX CM2290

* tag 'mmc-v5.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: tmio: reenable card irqs after the reset callback
  mmc: mediatek: Move cqhci init behind ungate clock
  mmc: cqhci: clear HALT state after CQE enable
  mmc: vub300: fix control-message timeouts
  mmc: dw_mmc: exynos: fix the finding clock sample value
  mmc: winbond: don't build on M68K
  mmc: sdhci-esdhc-imx: clear the buffer_read_ready to reset standard tuning circuit
  mmc: sdhci-pci: Read card detect from ACPI for Intel Merrifield
  mmc: sdhci: Map more voltage level to SDHCI_POWER_330

…rnel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Last minute fixes for crash on 32bit architectures when compression is
  in use. It's a regression introduced in 5.15-rc and I'd really like
  not let this into the final release, fixes via stable trees would add
  unnecessary delay.

  The problem is on 32bit architectures with highmem enabled, the pages
  for compression may need to be kmapped, while the patches removed that
  as we don't use GFP_HIGHMEM allocations anymore. The pages that don't
  come from local allocation still may be from highmem. Despite being on
  32bit there's enough such ARM machines in use so it's not a marginal
  issue.

  I did full reverts of the patches one by one instead of a huge one.
  There's one exception for the "lzo" revert as there was an
  intermediate patch touching the same code to make it compatible with
  subpage. I can't revert that one too, so the revert in lzo.c is
  manual. Qu Wenruo has worked on that with me and verified the changes"

* tag 'for-5.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Revert "btrfs: compression: drop kmap/kunmap from lzo"
  Revert "btrfs: compression: drop kmap/kunmap from zlib"
  Revert "btrfs: compression: drop kmap/kunmap from zstd"
  Revert "btrfs: compression: drop kmap/kunmap from generic helpers"

…ernel/git/rostedt/linux-trace

Pull tracing comment fixes from Steven Rostedt:

 - Some bots have informed me that some of the ftrace functions
   kernel-doc has formatting issues.

 - Also, fix my snake instinct.

* tag 'trace-v5.15-rc6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix misspelling of "missing"
  ftrace: Fix kernel-doc formatting issues

…/herbert/crypto-2.6

Pull crypto fix from Herbert Xu:
 "Fix a build-time warning in x86/sm4"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: x86/sm4 - Fix invalid section entry size

Merge misc fixes from Andrew Morton:
 "11 patches.

  Subsystems affected by this patch series: mm (memcg, memory-failure,
  oom-kill, secretmem, vmalloc, hugetlb, damon, and tools), and ocfs2"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/testing/selftests/vm/split_huge_page_test.c: fix application of sizeof to pointer
  mm/damon/core-test: fix wrong expectations for 'damon_split_regions_of()'
  mm: khugepaged: skip huge page collapse for special files
  mm, thp: bail out early in collapse_file for writeback page
  mm/vmalloc: fix numa spreading for large hash tables
  mm/secretmem: avoid letting secretmem_users drop to zero
  ocfs2: fix race between searching chunks and release journal_head from buffer_head
  mm/oom_kill.c: prevent a race between process_mrelease and exit_mmap
  mm: filemap: check if THP has hwpoisoned subpage for PMD page fault
  mm: hwpoison: remove the unnecessary THP check
  memcg: page_alloc: skip bulk allocator for __GFP_ACCOUNT

Nathan reported that because KASAN_SHADOW_OFFSET was not defined in
Kconfig, it prevents asan-stack from getting disabled with clang even
when CONFIG_KASAN_STACK is disabled: fix this by defining the
corresponding config.

Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Fixes: 8ad8b72 ("riscv: Add KASAN support")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

When calling this function, all the shadow memory is already populated
with kasan_early_shadow_pte which has PAGE_KERNEL protection.
kasan_populate_early_shadow write-protects the mapping of the range
of addresses passed in argument in zero_pte_populate, which actually
write-protects all the shadow memory mapping since kasan_early_shadow_pte
is used for all the shadow memory at this point. And then when using
memblock API to populate the shadow memory, the first write access to the
kernel stack triggers a trap. This becomes visible with the next commit
that contains a fix for asan-stack.

We already manually populate all the shadow memory in kasan_early_init
and we write-protect kasan_early_shadow_pte at the end of kasan_init
which makes the calls to kasan_populate_early_shadow superfluous so
we can remove them.

Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Fixes: e178d67 ("riscv/kasan: add KASAN_VMALLOC support")
Fixes: 8ad8b72 ("riscv: Add KASAN support")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

My snake instinct was on and I wrote "misssing" instead of "missing".

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Some functions had kernel-doc that used a comma instead of a hash to
separate the function name from the one line description.

Also, the "ftrace_is_dead()" had an incomplete description.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

This reverts commit 8c945d3.

The kmaps in compression code are still needed and cause crashes on
32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004
with enabled LZO or ZSTD compression.

The revert does not apply cleanly due to changes in a6e66e6
("btrfs: rework lzo_decompress_bio() to make it subpage compatible")
that reworked the page iteration so the revert is done to be equivalent
to the original code.

Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839
Tested-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

This reverts commit 696ab56.

The kmaps in compression code are still needed and cause crashes on
32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004
with enabled LZO or ZSTD compression.

Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839
Signed-off-by: David Sterba <dsterba@suse.com>

This reverts commit bbaf971.

The kmaps in compression code are still needed and cause crashes on
32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004
with enabled LZO or ZSTD compression.

Example stacktrace with ZSTD on a 32bit ARM machine:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = c4159ed3
  [00000000] *pgd=00000000
  Internal error: Oops: 5 [#1] PREEMPT SMP ARM
  Modules linked in:
  CPU: 0 PID: 210 Comm: kworker/u2:3 Not tainted 5.14.0-rc79+ torvalds#12
  Hardware name: Allwinner sun4i/sun5i Families
  Workqueue: btrfs-delalloc btrfs_work_helper
  PC is at mmiocpy+0x48/0x330
  LR is at ZSTD_compressStream_generic+0x15c/0x28c

  (mmiocpy) from [<c0629648>] (ZSTD_compressStream_generic+0x15c/0x28c)
  (ZSTD_compressStream_generic) from [<c06297dc>] (ZSTD_compressStream+0x64/0xa0)
  (ZSTD_compressStream) from [<c049444c>] (zstd_compress_pages+0x170/0x488)
  (zstd_compress_pages) from [<c0496798>] (btrfs_compress_pages+0x124/0x12c)
  (btrfs_compress_pages) from [<c043c068>] (compress_file_range+0x3c0/0x834)
  (compress_file_range) from [<c043c4ec>] (async_cow_start+0x10/0x28)
  (async_cow_start) from [<c0475c3c>] (btrfs_work_helper+0x100/0x230)
  (btrfs_work_helper) from [<c014ef68>] (process_one_work+0x1b4/0x418)
  (process_one_work) from [<c014f210>] (worker_thread+0x44/0x524)
  (worker_thread) from [<c0156aa4>] (kthread+0x180/0x1b0)
  (kthread) from [<c0100150>]

Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839
Signed-off-by: David Sterba <dsterba@suse.com>