Device tree binding for AMS/TAOS tsl2591 ambient light sensor.
This driver supports configuration via device tree and sysfs.
Supported channels for raw infrared light intensity,
raw combined light intensity and illuminance in lux.
The driver additionally supports iio events on lower and
upper thresholds.
This is a very-high sensitivity light-to-digital converter that
transforms light intensity into a digital signal.
Signed-off-by: Joe Sandom <joe.g.sandom@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210421221330.17007-2-joe.g.sandom@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Pull driver core fixes from Greg KH:
"Here are two driver fixes for driver core changes that happened in
5.13-rc1.
The clk driver fix resolves a many-reported issue with booting some
devices, and the USB typec fix resolves the reported problem of USB
systems on some embedded boards.
Both of these have been in linux-next this week with no reported
issues"
* tag 'driver-core-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
clk: Skip clk provider registration when np is NULL
usb: typec: tcpm: Don't block probing of consumers of "connector" nodes
Pull staging and IIO driver fixes from Greg KH:
"Here are some small IIO driver fixes and one Staging driver fix for
5.13-rc2.
Nothing major, just some resolutions for reported problems:
- gcc-11 bogus warning fix for rtl8723bs
- iio driver tiny fixes
All of these have been in linux-next for many days with no reported
issues"
* tag 'staging-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
iio: tsl2583: Fix division by a zero lux_val
iio: core: return ENODEV if ioctl is unknown
iio: core: fix ioctl handlers removal
iio: gyro: mpu3050: Fix reported temperature value
iio: hid-sensors: select IIO_TRIGGERED_BUFFER under HID_SENSOR_IIO_TRIGGER
iio: proximity: pulsedlight: Fix rumtime PM imbalance on error
iio: light: gp2ap002: Fix rumtime PM imbalance on error
staging: rtl8723bs: avoid bogus gcc warning
Pull USB fixes from Greg KH:
"Here are some small USB fixes for 5.13-rc2. They consist of a number
of resolutions for reported issues:
- typec fixes for found problems
- xhci fixes and quirk additions
- dwc3 driver fixes
- minor fixes found by Coverity
- cdc-wdm fixes for reported problems
All of these have been in linux-next for a few days with no reported
issues"
* tag 'usb-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (28 commits)
usb: core: hub: fix race condition about TRSMRCY of resume
usb: typec: tcpm: Fix SINK_DISCOVERY current limit for Rp-default
xhci: Add reset resume quirk for AMD xhci controller.
usb: xhci: Increase timeout for HC halt
xhci: Do not use GFP_KERNEL in (potentially) atomic context
xhci: Fix giving back cancelled URBs even if halted endpoint can't reset
xhci-pci: Allow host runtime PM as default for Intel Alder Lake xHCI
usb: musb: Fix an error message
usb: typec: tcpm: Fix wrong handling for Not_Supported in VDM AMS
usb: typec: tcpm: Send DISCOVER_IDENTITY from dedicated work
usb: typec: ucsi: Retrieve all the PDOs instead of just the first 4
usb: fotg210-hcd: Fix an error message
docs: usb: function: Modify path name
usb: dwc3: omap: improve extcon initialization
usb: typec: ucsi: Put fwnode in any case during ->probe()
usb: typec: tcpm: Fix wrong handling in GET_SINK_CAP
usb: dwc2: Remove obsolete MODULE_ constants from platform.c
usb: dwc3: imx8mp: fix error return code in dwc3_imx8mp_probe()
usb: dwc3: imx8mp: detect dwc3 core node via compatible string
usb: dwc3: gadget: Return success always for kick transfer in ep queue
...
Pull timer fixes from Thomas Gleixner:
"Two fixes for timers:
- Use the ALARM feature check in the alarmtimer core code insted of
the old method of checking for the set_alarm() callback.
Drivers can have that callback set but the feature bit cleared. If
such a RTC device is selected then alarms wont work.
- Use a proper define to let the preprocessor check whether Hyper-V
VDSO clocksource should be active.
The code used a constant in an enum with #ifdef, which evaluates to
always false and disabled the clocksource for VDSO"
* tag 'timers-urgent-2021-05-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource/drivers/hyper-v: Re-enable VDSO_CLOCKMODE_HVCLOCK on X86
alarmtimer: Check RTC features instead of ops
Pull xen fixes from Juergen Gross:
- two patches for error path fixes
- a small series for fixing a regression with swiotlb with Xen on Arm
* tag 'for-linus-5.13b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/swiotlb: check if the swiotlb has already been initialized
arm64: do not set SWIOTLB_NO_FORCE when swiotlb is required
xen/arm: move xen_swiotlb_detect to arm/swiotlb-xen.h
xen/unpopulated-alloc: fix error return code in fill_list()
xen/gntdev: fix gntdev_mmap() error exit path
Pull x86 fixes from Borislav Petkov:
"The three SEV commits are not really urgent material. But we figured
since getting them in now will avoid a huge amount of conflicts
between future SEV changes touching tip, the kvm and probably other
trees, sending them to you now would be best.
The idea is that the tip, kvm etc branches for 5.14 will all base
ontop of -rc2 and thus everything will be peachy. What is more, those
changes are purely mechanical and defines movement so they should be
fine to go now (famous last words).
Summary:
- Enable -Wundef for the compressed kernel build stage
- Reorganize SEV code to streamline and simplify future development"
* tag 'x86_urgent_for_v5.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot/compressed: Enable -Wundef
x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG
x86/sev: Move GHCB MSR protocol and NAE definitions in a common header
x86/sev-es: Rename sev-es.{ch} to sev.{ch}
Pull powerpc fixes from Michael Ellerman:
- Fix a regression in the conversion of the 64-bit BookE interrupt
entry to C.
- Fix KVM hosts running with the hash MMU since the recent KVM gfn
changes.
- Fix a deadlock in our paravirt spinlocks when hcall tracing is
enabled.
- Several fixes for oopses in our runtime code patching for security
mitigations.
- A couple of minor fixes for the recent conversion of 32-bit interrupt
entry/exit to C.
- Fix __get_user() causing spurious crashes in sigreturn due to a bad
inline asm constraint, spotted with GCC 11.
- A fix for the way we track IRQ masking state vs NMI interrupts when
using the new scv system call entry path.
- A couple more minor fixes.
Thanks to Cédric Le Goater, Christian Zigotzky, Christophe Leroy,
Naveen N. Rao, Nicholas Piggin Paul Menzel, and Sean Christopherson.
* tag 'powerpc-5.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64e/interrupt: Fix nvgprs being clobbered
powerpc/64s: Make NMI record implicitly soft-masked code as irqs disabled
powerpc/64s: Fix stf mitigation patching w/strict RWX & hash
powerpc/64s: Fix entry flush patching w/strict RWX & hash
powerpc/64s: Fix crashes when toggling entry flush barrier
powerpc/64s: Fix crashes when toggling stf barrier
KVM: PPC: Book3S HV: Fix kvm_unmap_gfn_range_hv() for Hash MMU
powerpc/legacy_serial: Fix UBSAN: array-index-out-of-bounds
powerpc/signal: Fix possible build failure with unsafe_copy_fpr_{to/from}_user
powerpc/uaccess: Fix __get_user() with CONFIG_CC_HAS_ASM_GOTO_OUTPUT
powerpc/pseries: warn if recursing into the hcall tracing code
powerpc/pseries: use notrace hcall variant for H_CEDE idle
powerpc/pseries: Don't trace hcall tracing wrapper
powerpc/pseries: Fix hcall tracing recursion in pv queued spinlocks
powerpc/syscall: Calling kuap_save_and_lock() is wrong
powerpc/interrupts: Fix kuep_unlock() call
Pull scheduler fixes from Ingo Molnar:
"Fix an idle CPU selection bug, and an AMD Ryzen maximum frequency
enumeration bug"
* tag 'sched-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations
sched/fair: Fix clearing of has_idle_cores flag in select_idle_cpu()
Pull objtool fixes from Ingo Molnar:
"Fix a couple of endianness bugs that crept in"
* tag 'objtool-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool/x86: Fix elf_add_alternative() endianness
objtool: Fix elf_create_undef_symbol() endianness
Pull irq fix from Ingo Molnar:
"Fix build warning on SH"
* tag 'irq-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sh: Remove unused variable
Pull x86 stack randomization fix from Ingo Molnar:
"Fix an assembly constraint that affected LLVM up to version 12"
* tag 'core-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stack: Replace "o" output with "r" input constraint
Merge misc fixes from Andrew Morton:
"13 patches.
Subsystems affected by this patch series: resource, squashfs, hfsplus,
modprobe, and mm (hugetlb, slub, userfaultfd, ksm, pagealloc, kasan,
pagemap, and ioremap)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/ioremap: fix iomap_max_page_shift
docs: admin-guide: update description for kernel.modprobe sysctl
hfsplus: prevent corruption in shrinking truncate
mm/filemap: fix readahead return types
kasan: fix unit tests with CONFIG_UBSAN_LOCAL_BOUNDS enabled
mm: fix struct page layout on 32-bit systems
ksm: revert "use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from_tree()"
userfaultfd: release page in error path to avoid BUG_ON
squashfs: fix divide error in calculate_skip()
kernel/resource: fix return code check in __request_free_mem_region
mm, slub: move slub_debug static key enabling outside slab_mutex
mm/hugetlb: fix cow where page writtable in child
mm/hugetlb: fix F_SEAL_FUTURE_WRITE
Pull ARC fixes from Vineet Gupta:
- PAE fixes
- syscall num check off-by-one bug
- misc fixes
* tag 'arc-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: mm: Use max_high_pfn as a HIGHMEM zone border
ARC: mm: PAE: use 40-bit physical page mask
ARC: entry: fix off-by-one error in syscall number validation
ARC: kgdb: add 'fallthrough' to prevent a warning
arc: Fix typos/spellos
Pull block fixes from Jens Axboe:
- Fix for shared tag set exit (Bart)
- Correct ioctl range for zoned ioctls (Damien)
- Removed dead/unused function (Lin)
- Fix perf regression for shared tags (Ming)
- Fix out-of-bounds issue with kyber and preemption (Omar)
- BFQ merge fix (Paolo)
- Two error handling fixes for nbd (Sun)
- Fix weight update in blk-iocost (Tejun)
- NVMe pull request (Christoph):
- correct the check for using the inline bio in nvmet (Chaitanya
Kulkarni)
- demote unsupported command warnings (Chaitanya Kulkarni)
- fix corruption due to double initializing ANA state (me, Hou Pu)
- reset ns->file when open fails (Daniel Wagner)
- fix a NULL deref when SEND is completed with error in nvmet-rdma
(Michal Kalderon)
- Fix kernel-doc warning (Bart)
* tag 'block-5.13-2021-05-14' of git://git.kernel.dk/linux-block:
block/partitions/efi.c: Fix the efi_partition() kernel-doc header
blk-mq: Swap two calls in blk_mq_exit_queue()
blk-mq: plug request for shared sbitmap
nvmet: use new ana_log_size instead the old one
nvmet: seset ns->file when open fails
nbd: share nbd_put and return by goto put_nbd
nbd: Fix NULL pointer in flush_workqueue
blkdev.h: remove unused codes blk_account_rq
block, bfq: avoid circular stable merges
blk-iocost: fix weight updates of inner active iocgs
nvmet: demote fabrics cmd parse err msg to debug
nvmet: use helper to remove the duplicate code
nvmet: demote discovery cmd parse err msg to debug
nvmet-rdma: Fix NULL deref when SEND is completed with error
nvmet: fix inline bio check for passthru
nvmet: fix inline bio check for bdev-ns
nvme-multipath: fix double initialization of ANA state
kyber: fix out of bounds access when preempted
block: uapi: fix comment about block device ioctl
Pull io_uring fixes from Jens Axboe:
"Just a few minor fixes/changes:
- Fix issue with double free race for linked timeout completions
- Fix reference issue with timeouts
- Remove last few places that make SQPOLL special, since it's just an
io thread now.
- Bump maximum allowed registered buffers, as we don't allocate as
much anymore"
* tag 'io_uring-5.13-2021-05-14' of git://git.kernel.dk/linux-block:
io_uring: increase max number of reg buffers
io_uring: further remove sqpoll limits on opcodes
io_uring: fix ltout double free on completion race
io_uring: fix link timeout refs
Pull erofs fixes from Gao Xiang:
"This mainly fixes 1 lcluster-sized pclusters for the big pcluster
feature, which can be forcely generated by mkfs as a specific on-disk
case for per-(sub)file compression strategies but missed to handle in
runtime properly.
Also, documentation updates are included to fix the broken
illustration due to the ReST conversion by accident and complete the
big pcluster introduction.
Summary:
- update documentation to fix the broken illustration due to ReST
conversion by accident at that time and complete the big pcluster
introduction
- fix 1 lcluster-sized pclusters for the big pcluster feature"
* tag 'erofs-for-5.13-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: fix 1 lcluster-sized pcluster for big pcluster
erofs: update documentation about data compression
erofs: fix broken illustration in documentation
Pull libnvdimm fixes from Dan Williams:
"A regression fix for a bootup crash condition introduced in this merge
window and some other minor fixups:
- Fix regression in ACPI NFIT table handling leading to crashes and
driver load failures.
- Move the nvdimm mailing list
- Miscellaneous minor fixups"
* tag 'libnvdimm-fixes-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
ACPI: NFIT: Fix support for variable 'SPA' structure size
MAINTAINERS: Move nvdimm mailing list
tools/testing/nvdimm: Make symbol '__nfit_test_ioremap' static
libnvdimm: Remove duplicate struct declaration
Pull dax fixes from Dan Williams:
"A fix for a hang condition due to missed wakeups in the filesystem-dax
core when exercised by virtiofs.
This bug has been there from the beginning, but the condition has
not triggered on other filesystems since they hold a lock over
invalidation events"
* tag 'dax-fixes-5.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: Wake up all waiters after invalidating dax entry
dax: Add a wakeup mode parameter to put_unlocked_entry()
dax: Add an enum for specifying dax wakup mode
Pull more drm fixes from Dave Airlie:
"Looks like I wasn't the only one not fully switched on this week. The
msm pull has a missing tag so I missed it, and i915 team were a bit
late. In my defence I did have a day with the roof of my home office
removed, so was sitting at my kids desk.
msm:
- dsi regression fix
- dma-buf pinning fix
- displayport fixes
- llc fix
i915:
- Fix active callback alignment annotations and subsequent crashes
- Retract link training strategy to slow and wide, again
- Avoid division by zero on gen2
- Use correct width reads for C0DRB3/C1DRB3 registers
- Fix double free in pdp allocation failure path
- Fix HDMI 2.1 PCON downstream caps check"
* tag 'drm-fixes-2021-05-15' of git://anongit.freedesktop.org/drm/drm:
drm/i915: Use correct downstream caps for check Src-Ctl mode for PCON
drm/i915/overlay: Fix active retire callback alignment
drm/i915: Fix crash in auto_retire
drm/i915/gt: Fix a double free in gen8_preallocate_top_level_pdp
drm/i915: Read C0DRB3/C1DRB3 as 16 bits again
drm/i915: Avoid div-by-zero on gen2
drm/i915/dp: Use slow and wide link training for everything
drm/msm/dp: initialize audio_comp when audio starts
drm/msm/dp: check sink_count before update is_connected status
drm/msm: fix minor version to indicate MSM_PARAM_SUSPENDS support
drm/msm/dsi: fix msm_dsi_phy_get_clk_provider return code
drm/msm/dsi: dsi_phy_28nm_8960: fix uninitialized variable access
drm/msm: fix LLC not being enabled for mmu500 targets
drm/msm: Do not unpin/evict exported dma-buf's
I believe there are some issues introduced by commit 31651c6071
("hfsplus: avoid deadlock on file truncation")
HFS+ has extent records which always contains 8 extents. In case the
first extent record in catalog file gets full, new ones are allocated from
extents overflow file.
In case shrinking truncate happens to middle of an extent record which
locates in extents overflow file, the logic in hfsplus_file_truncate() was
changed so that call to hfs_brec_remove() is not guarded any more.
Right action would be just freeing the extents that exceed the new size
inside extent record by calling hfsplus_free_extents(), and then check if
the whole extent record should be removed. However since the guard
(blk_cnt > start) is now after the call to hfs_brec_remove(), this has
unfortunate effect that the last matching extent record is removed
unconditionally.
To reproduce this issue, create a file which has at least 10 extents, and
then perform shrinking truncate into middle of the last extent record, so
that the number of remaining extents is not under or divisible by 8. This
causes the last extent record (8 extents) to be removed totally instead of
truncating into middle of it. Thus this causes corruption, and lost data.
Fix for this is simply checking if the new truncated end is below the
start of this extent record, making it safe to remove the full extent
record. However call to hfs_brec_remove() can't be moved to it's previous
place since we're dropping ->tree_lock and it can cause a race condition
and the cached info being invalidated possibly corrupting the node data.
Another issue is related to this one. When entering into the block
(blk_cnt > start) we are not holding the ->tree_lock. We break out from
the loop not holding the lock, but hfs_find_exit() does unlock it. Not
sure if it's possible for someone else to take the lock under our feet,
but it can cause hard to debug errors and premature unlocking. Even if
there's no real risk of it, the locking should still always be kept in
balance. Thus taking the lock now just before the check.
Link: https://lkml.kernel.org/r/20210429165139.3082828-1-jouni.roivas@tuxera.com
Fixes: 31651c6071 ("hfsplus: avoid deadlock on file truncation")
Signed-off-by: Jouni Roivas <jouni.roivas@tuxera.com>
Reviewed-by: Anton Altaparmakov <anton@tuxera.com>
Cc: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Cc: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
32-bit architectures which expect 8-byte alignment for 8-byte integers and
need 64-bit DMA addresses (arm, mips, ppc) had their struct page
inadvertently expanded in 2019. When the dma_addr_t was added, it forced
the alignment of the union to 8 bytes, which inserted a 4 byte gap between
'flags' and the union.
Fix this by storing the dma_addr_t in one or two adjacent unsigned longs.
This restores the alignment to that of an unsigned long. We always
store the low bits in the first word to prevent the PageTail bit from
being inadvertently set on a big endian platform. If that happened,
get_user_pages_fast() racing against a page which was freed and
reallocated to the page_pool could dereference a bogus compound_head(),
which would be hard to trace back to this cause.
Link: https://lkml.kernel.org/r/20210510153211.1504886-1-willy@infradead.org
Fixes: c25fff7171 ("mm: add dma_addr_t to struct page")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Matteo Croce <mcroce@linux.microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Consider the following sequence of events:
1. Userspace issues a UFFD ioctl, which ends up calling into
shmem_mfill_atomic_pte(). We successfully account the blocks, we
shmem_alloc_page(), but then the copy_from_user() fails. We return
-ENOENT. We don't release the page we allocated.
2. Our caller detects this error code, tries the copy_from_user() after
dropping the mmap_lock, and retries, calling back into
shmem_mfill_atomic_pte().
3. Meanwhile, let's say another process filled up the tmpfs being used.
4. So shmem_mfill_atomic_pte() fails to account blocks this time, and
immediately returns - without releasing the page.
This triggers a BUG_ON in our caller, which asserts that the page
should always be consumed, unless -ENOENT is returned.
To fix this, detect if we have such a "dangling" page when accounting
fails, and if so, release it before returning.
Link: https://lkml.kernel.org/r/20210428230858.348400-1-axelrasmussen@google.com
Fixes: cb658a453b ("userfaultfd: shmem: avoid leaking blocks and used blocks in UFFDIO_COPY")
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reported-by: Hugh Dickins <hughd@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sysbot has reported a "divide error" which has been identified as being
caused by a corrupted file_size value within the file inode. This value
has been corrupted to a much larger value than expected.
Calculate_skip() is passed i_size_read(inode) >> msblk->block_log. Due to
the file_size value corruption this overflows the int argument/variable in
that function, leading to the divide error.
This patch changes the function to use u64. This will accommodate any
unexpectedly large values due to corruption.
The value returned from calculate_skip() is clamped to be never more than
SQUASHFS_CACHED_BLKS - 1, or 7. So file_size corruption does not lead to
an unexpectedly large return result here.
Link: https://lkml.kernel.org/r/20210507152618.9447-1-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: <syzbot+e8f781243ce16ac2f962@syzkaller.appspotmail.com>
Reported-by: <syzbot+7b98870d4fec9447b951@syzkaller.appspotmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul E. McKenney reported [1] that commit 1f0723a4c0 ("mm, slub: enable
slub_debug static key when creating cache with explicit debug flags")
results in the lockdep complaint:
======================================================
WARNING: possible circular locking dependency detected
5.12.0+ #15 Not tainted
------------------------------------------------------
rcu_torture_sta/109 is trying to acquire lock:
ffffffff96063cd0 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x9/0x20
but task is already holding lock:
ffffffff96173c28 (slab_mutex){+.+.}-{3:3}, at: kmem_cache_create_usercopy+0x2d/0x250
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (slab_mutex){+.+.}-{3:3}:
lock_acquire+0xb9/0x3a0
__mutex_lock+0x8d/0x920
slub_cpu_dead+0x15/0xf0
cpuhp_invoke_callback+0x17a/0x7c0
cpuhp_invoke_callback_range+0x3b/0x80
_cpu_down+0xdf/0x2a0
cpu_down+0x2c/0x50
device_offline+0x82/0xb0
remove_cpu+0x1a/0x30
torture_offline+0x80/0x140
torture_onoff+0x147/0x260
kthread+0x10a/0x140
ret_from_fork+0x22/0x30
-> #0 (cpu_hotplug_lock){++++}-{0:0}:
check_prev_add+0x8f/0xbf0
__lock_acquire+0x13f0/0x1d80
lock_acquire+0xb9/0x3a0
cpus_read_lock+0x21/0xa0
static_key_enable+0x9/0x20
__kmem_cache_create+0x38d/0x430
kmem_cache_create_usercopy+0x146/0x250
kmem_cache_create+0xd/0x10
rcu_torture_stats+0x79/0x280
kthread+0x10a/0x140
ret_from_fork+0x22/0x30
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(slab_mutex);
lock(cpu_hotplug_lock);
lock(slab_mutex);
lock(cpu_hotplug_lock);
*** DEADLOCK ***
1 lock held by rcu_torture_sta/109:
#0: ffffffff96173c28 (slab_mutex){+.+.}-{3:3}, at: kmem_cache_create_usercopy+0x2d/0x250
stack backtrace:
CPU: 3 PID: 109 Comm: rcu_torture_sta Not tainted 5.12.0+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
dump_stack+0x6d/0x89
check_noncircular+0xfe/0x110
? lock_is_held_type+0x98/0x110
check_prev_add+0x8f/0xbf0
__lock_acquire+0x13f0/0x1d80
lock_acquire+0xb9/0x3a0
? static_key_enable+0x9/0x20
? mark_held_locks+0x49/0x70
cpus_read_lock+0x21/0xa0
? static_key_enable+0x9/0x20
static_key_enable+0x9/0x20
__kmem_cache_create+0x38d/0x430
kmem_cache_create_usercopy+0x146/0x250
? rcu_torture_stats_print+0xd0/0xd0
kmem_cache_create+0xd/0x10
rcu_torture_stats+0x79/0x280
? rcu_torture_stats_print+0xd0/0xd0
kthread+0x10a/0x140
? kthread_park+0x80/0x80
ret_from_fork+0x22/0x30
This is because there's one order of locking from the hotplug callbacks:
lock(cpu_hotplug_lock); // from hotplug machinery itself
lock(slab_mutex); // in e.g. slab_mem_going_offline_callback()
And commit 1f0723a4c0 made the reverse sequence possible:
lock(slab_mutex); // in kmem_cache_create_usercopy()
lock(cpu_hotplug_lock); // kmem_cache_open() -> static_key_enable()
The simplest fix is to move static_key_enable() to a place before slab_mutex is
taken. That means kmem_cache_create_usercopy() in mm/slab_common.c which is not
ideal for SLUB-specific code, but the #ifdef CONFIG_SLUB_DEBUG makes it
at least self-contained and obvious.
[1] https://lore.kernel.org/lkml/20210502171827.GA3670492@paulmck-ThinkPad-P17-Gen-1/
Link: https://lkml.kernel.org/r/20210504120019.26791-1-vbabka@suse.cz
Fixes: 1f0723a4c0 ("mm, slub: enable slub_debug static key when creating cache with explicit debug flags")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
