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Linux kernel
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the problems which may result by upgrading your kernel.
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Pull perf event fix from Ingo Molnar:
"Fix race between perf_event_free_task() and perf_event_release_kernel()
that can result in missed wakeups and hung tasks"
* tag 'perf-urgent-2024-06-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix missing wakeup when waiting for context reference
Pull locking doc fix from Ingo Molnar:
"Fix typos in the kerneldoc of some of the atomic APIs"
* tag 'locking-urgent-2024-06-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomic: scripts: fix ${atomic}_sub_and_test() kerneldoc
In our production environment, we found many hung tasks which are
blocked for more than 18 hours. Their call traces are like this:
[346278.191038] __schedule+0x2d8/0x890
[346278.191046] schedule+0x4e/0xb0
[346278.191049] perf_event_free_task+0x220/0x270
[346278.191056] ? init_wait_var_entry+0x50/0x50
[346278.191060] copy_process+0x663/0x18d0
[346278.191068] kernel_clone+0x9d/0x3d0
[346278.191072] __do_sys_clone+0x5d/0x80
[346278.191076] __x64_sys_clone+0x25/0x30
[346278.191079] do_syscall_64+0x5c/0xc0
[346278.191083] ? syscall_exit_to_user_mode+0x27/0x50
[346278.191086] ? do_syscall_64+0x69/0xc0
[346278.191088] ? irqentry_exit_to_user_mode+0x9/0x20
[346278.191092] ? irqentry_exit+0x19/0x30
[346278.191095] ? exc_page_fault+0x89/0x160
[346278.191097] ? asm_exc_page_fault+0x8/0x30
[346278.191102] entry_SYSCALL_64_after_hwframe+0x44/0xae
The task was waiting for the refcount become to 1, but from the vmcore,
we found the refcount has already been 1. It seems that the task didn't
get woken up by perf_event_release_kernel() and got stuck forever. The
below scenario may cause the problem.
Thread A Thread B
... ...
perf_event_free_task perf_event_release_kernel
...
acquire event->child_mutex
...
get_ctx
... release event->child_mutex
acquire ctx->mutex
...
perf_free_event (acquire/release event->child_mutex)
...
release ctx->mutex
wait_var_event
acquire ctx->mutex
acquire event->child_mutex
# move existing events to free_list
release event->child_mutex
release ctx->mutex
put_ctx
... ...
In this case, all events of the ctx have been freed, so we couldn't
find the ctx in free_list and Thread A will miss the wakeup. It's thus
necessary to add a wakeup after dropping the reference.
Fixes: 1cf8dfe8a661 ("perf/core: Fix race between close() and fork()")
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20240513103948.33570-1-haifeng.xu@shopee.com
Pull misc fixes from Andrew Morton:
"14 hotfixes, 6 of which are cc:stable.
All except the nilfs2 fix affect MM and all are singletons - see the
chagelogs for details"
* tag 'mm-hotfixes-stable-2024-06-07-15-24' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
nilfs2: fix nilfs_empty_dir() misjudgment and long loop on I/O errors
mm: fix xyz_noprof functions calling profiled functions
codetag: avoid race at alloc_slab_obj_exts
mm/hugetlb: do not call vma_add_reservation upon ENOMEM
mm/ksm: fix ksm_zero_pages accounting
mm/ksm: fix ksm_pages_scanned accounting
kmsan: do not wipe out origin when doing partial unpoisoning
vmalloc: check CONFIG_EXECMEM in is_vmalloc_or_module_addr()
mm: page_alloc: fix highatomic typing in multi-block buddies
nilfs2: fix potential kernel bug due to lack of writeback flag waiting
memcg: remove the lockdep assert from __mod_objcg_mlstate()
mm: arm64: fix the out-of-bounds issue in contpte_clear_young_dirty_ptes
mm: huge_mm: fix undefined reference to `mthp_stats' for CONFIG_SYSFS=n
mm: drop the 'anon_' prefix for swap-out mTHP counters
For ${atomic}_sub_and_test() the @i parameter is the value to subtract,
not add. Fix the typo in the kerneldoc template and generate the headers
with this update.
Fixes: ad8110706f38 ("locking/atomic: scripts: generate kerneldoc comments")
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20240515133844.3502360-1-cmllamas@google.com
Pull gpio fixes from Bartosz Golaszewski:
- interrupt handling and Kconfig fixes for gpio-tqmx86
- add a buffer for storing output values in gpio-tqmx86 as reading back
the registers always returns the input values
- add missing MODULE_DESCRIPTION()s to several GPIO drivers
* tag 'gpio-fixes-for-v6.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: add missing MODULE_DESCRIPTION() macros
gpio: tqmx86: fix broken IRQ_TYPE_EDGE_BOTH interrupt type
gpio: tqmx86: store IRQ trigger type and unmask status separately
gpio: tqmx86: introduce shadow register for GPIO output value
gpio: tqmx86: fix typo in Kconfig label
The error handling in nilfs_empty_dir() when a directory folio/page read
fails is incorrect, as in the old ext2 implementation, and if the
folio/page cannot be read or nilfs_check_folio() fails, it will falsely
determine the directory as empty and corrupt the file system.
In addition, since nilfs_empty_dir() does not immediately return on a
failed folio/page read, but continues to loop, this can cause a long loop
with I/O if i_size of the directory's inode is also corrupted, causing the
log writer thread to wait and hang, as reported by syzbot.
Fix these issues by making nilfs_empty_dir() immediately return a false
value (0) if it fails to get a directory folio/page.
Link: https://lkml.kernel.org/r/20240604134255.7165-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+c8166c541d3971bf6c87@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c8166c541d3971bf6c87
Fixes: 2ba466d74ed7 ("nilfs2: directory entry operations")
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull ata fixes from Niklas Cassel:
- Add a quirk for three different devices that have shown issues with
LPM (link power management). These devices appear to not implement
LPM properly, since we see command timeouts when enabling LPM. The
quirk disables LPM for these problematic devices. (Me)
- Do not apply the Intel PCS quirk on Alder Lake. The quirk is not
needed and was originally added by mistake when LPM support was
enabled for this AHCI controller. Enabling the quirk when not needed
causes the the controller to not be able to detect the connected
devices on some platforms.
* tag 'ata-6.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
ata: libata-core: Add ATA_HORKAGE_NOLPM for Apacer AS340
ata: libata-core: Add ATA_HORKAGE_NOLPM for AMD Radeon S3 SSD
ata: libata-core: Add ATA_HORKAGE_NOLPM for Crucial CT240BX500SSD1
ata: ahci: Do not apply Intel PCS quirk on Intel Alder Lake
Pull block fixes from Jens Axboe:
- Fix for null_blk block size validation (Andreas)
- NVMe pull request via Keith:
- Use reserved tags for special fabrics operations (Chunguang)
- Persistent Reservation status masking fix (Weiwen)
* tag 'block-6.10-20240607' of git://git.kernel.dk/linux:
null_blk: fix validation of block size
nvme: fix nvme_pr_* status code parsing
nvme-fabrics: use reserved tag for reg read/write command
On x86, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/gpio/gpio-gw-pld.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/gpio/gpio-mc33880.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/gpio/gpio-pcf857x.o
Add the missing invocations of the MODULE_DESCRIPTION() macro,
including the one missing in gpio-pl061.c, which is not built for x86.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240606-md-drivers-gpio-v1-1-cb42d240ca5c@quicinc.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Grepping /proc/allocinfo for "noprof" reveals several xyz_noprof
functions, which means internally they are calling profiled functions.
This should never happen as such calls move allocation charge from a
higher level location where it should be accounted for into these lower
level helpers. Fix this by replacing profiled function calls with noprof
ones.
Link: https://lkml.kernel.org/r/20240531205350.3973009-1-surenb@google.com
Fixes: b951aaff5035 ("mm: enable page allocation tagging")
Fixes: e26d8769da6d ("mempool: hook up to memory allocation profiling")
Fixes: 88ae5fb755b0 ("mm: vmalloc: enable memory allocation profiling")
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Kees Cook <kees@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull x86 fixes from Ingo Molnar:
"Miscellaneous topology parsing fixes:
- Fix topology parsing regression on older CPUs in the new AMD/Hygon
parser
- Fix boot crash on odd Intel Quark and similar CPUs that do not fill
out cpuinfo_x86::x86_clflush_size and zero out
cpuinfo_x86::x86_cache_alignment as a result.
Provide 32 bytes as a general fallback value.
- Fix topology enumeration on certain rare CPUs where the BIOS locks
certain CPUID leaves and the kernel unlocked them late, which broke
with the new topology parsing code. Factor out this unlocking logic
and move it earlier in the parsing sequence"
* tag 'x86-urgent-2024-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology/intel: Unlock CPUID before evaluating anything
x86/cpu: Provide default cache line size if not enumerated
x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 and greater
Commit 7627a0edef54 ("ata: ahci: Drop low power policy board type")
dropped the board_ahci_low_power board type, and instead enables LPM if:
-The AHCI controller reports that it supports LPM (Partial/Slumber), and
-CONFIG_SATA_MOBILE_LPM_POLICY != 0, and
-The port is not defined as external in the per port PxCMD register, and
-The port is not defined as hotplug capable in the per port PxCMD
register.
Partial and Slumber LPM states can either be initiated by HIPM or DIPM.
For HIPM (host initiated power management) to get enabled, both the AHCI
controller and the drive have to report that they support HIPM.
For DIPM (device initiated power management) to get enabled, only the
drive has to report that it supports DIPM. However, the HBA will reject
device requests to enter LPM states which the HBA does not support.
The problem is that Apacer AS340 drives do not handle low power modes
correctly. The problem was most likely not seen before because no one
had used this drive with a AHCI controller with LPM enabled.
Add a quirk so that we do not enable LPM for this drive, since we see
command timeouts if we do (even though the drive claims to support DIPM).
Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type")
Cc: stable@vger.kernel.org
Reported-by: Tim Teichmann <teichmanntim@outlook.de>
Closes: https://lore.kernel.org/linux-ide/87bk4pbve8.ffs@tglx/
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Pull io_uring fixes from Jens Axboe:
- Fix a locking order issue with setting max async thread workers
(Hagar)
- Fix for a NULL pointer dereference for failed async flagged requests
using ring provided buffers. This doesn't affect the current kernel,
but it does affect older kernels, and is being queued up for 6.10
just to make the stable process easier (me)
- Fix for NAPI timeout calculations for how long to busy poll, and
subsequently how much to sleep post that if a wait timeout is passed
in (me)
- Fix for a regression in this release cycle, where we could end up
using a partially unitialized match value for io-wq (Su)
* tag 'io_uring-6.10-20240607' of git://git.kernel.dk/linux:
io_uring: fix possible deadlock in io_register_iowq_max_workers()
io_uring/io-wq: avoid garbage value of 'match' in io_wq_enqueue()
io_uring/napi: fix timeout calculation
io_uring: check for non-NULL file pointer in io_file_can_poll()
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