Pull block fixes from Jens Axboe:
- Fix for a regression in this series for loop and read/write iterator
handling
- zone append block update tweak
- remove a broken IO priority test
- NVMe pull request via Christoph:
- unblock ctrl state transition for firmware update (Daniel
Wagner)
* tag 'block-6.15-20250509' of git://git.kernel.dk/linux:
block: remove test of incorrect io priority level
nvme: unblock ctrl state transition for firmware update
block: only update request sector if needed
loop: Add sanity check for read/write_iter
In case of a ZONE APPEND write, regardless of native ZONE APPEND or the
emulation layer in the zone write plugging code, the sector the data got
written to by the device needs to be updated in the bio.
At the moment, this is done for every native ZONE APPEND write and every
request that is flagged with 'BIO_ZONE_WRITE_PLUGGING'. But thus
superfluously updates the sector for regular writes to a zoned block
device.
Check if a bio is a native ZONE APPEND write or if the bio is flagged as
'BIO_EMULATES_ZONE_APPEND', meaning the block layer's zone write plugging
code handles the ZONE APPEND and translates it into a regular write and
back. Only if one of these two criterion is met, update the sector in the
bio upon completion.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/dea089581cb6b777c1cd1500b38ac0b61df4b2d1.1746530748.git.jth@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block fixes from Jens Axboe:
- Fix autoloading of drivers from stat*(2)
- Fix losing read-ahead setting one suspend/resume, when a device is
re-probed.
- Fix race between setting the block size and page cache updates.
Includes a helper that a coming XFS fix will use as well.
- ublk cancelation fixes.
- ublk selftest additions and fixes.
- NVMe pull via Christoph:
- fix an out-of-bounds access in nvmet_enable_port (Richard
Weinberger)
* tag 'block-6.15-20250424' of git://git.kernel.dk/linux:
ublk: fix race between io_uring_cmd_complete_in_task and ublk_cancel_cmd
ublk: call ublk_dispatch_req() for handling UBLK_U_IO_NEED_GET_DATA
block: don't autoload drivers on blk-cgroup configuration
block: don't autoload drivers on stat
block: remove the backing_inode variable in bdev_statx
block: move blkdev_{get,put} _no_open prototypes out of blkdev.h
block: never reduce ra_pages in blk_apply_bdi_limits
selftests: ublk: common: fix _get_disk_dev_t for pre-9.0 coreutils
selftests: ublk: remove useless 'delay_us' from 'struct dev_ctx'
selftests: ublk: fix recover test
block: hoist block size validation code to a separate function
block: fix race between set_blocksize and read paths
nvmet: fix out-of-bounds access in nvmet_enable_port
When the user increased the read-ahead size through sysfs this value
currently get lost if the device is reprobe, including on a resume
from suspend.
As there is no hardware limitation for the read-ahead size there is
no real need to reset it or track a separate hardware limitation
like for max_sectors.
This restores the pre-atomic queue limit behavior in the sd driver as
sd did not use blk_queue_io_opt and thus never updated the read ahead
size to the value based of the optimal I/O, but changes behavior for
all other drivers. As the new behavior seems useful and sd is the
driver for which the readahead size tweaks are most useful that seems
like a worthwhile trade off.
Fixes: 804e498e04 ("sd: convert to the atomic queue limits API")
Reported-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250424082521.1967286-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the new large sector size support, it's now the case that
set_blocksize can change i_blksize and the folio order in a manner that
conflicts with a concurrent reader and causes a kernel crash.
Specifically, let's say that udev-worker calls libblkid to detect the
labels on a block device. The read call can create an order-0 folio to
read the first 4096 bytes from the disk. But then udev is preempted.
Next, someone tries to mount an 8k-sectorsize filesystem from the same
block device. The filesystem calls set_blksize, which sets i_blksize to
8192 and the minimum folio order to 1.
Now udev resumes, still holding the order-0 folio it allocated. It then
tries to schedule a read bio and do_mpage_readahead tries to create
bufferheads for the folio. Unfortunately, blocks_per_folio == 0 because
the page size is 4096 but the blocksize is 8192 so no bufferheads are
attached and the bh walk never sets bdev. We then submit the bio with a
NULL block device and crash.
Therefore, truncate the page cache after flushing but before updating
i_blksize. However, that's not enough -- we also need to lock out file
IO and page faults during the update. Take both the i_rwsem and the
invalidate_lock in exclusive mode for invalidations, and in shared mode
for read/write operations.
I don't know if this is the correct fix, but xfs/259 found it.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/174543795699.4139148.2086129139322431423.stgit@frogsfrogsfrogs
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull vfs fixes from Christian Brauner:
- Revert the hfs{plus} deprecation warning that's also included in this
pull request. The commit introducing the deprecation warning resides
rather early in this branch. So simply dropping it would've rebased
all other commits which I decided to avoid. Hence the revert in the
same branch
[ Background - the deprecation warning discussion resulted in people
stepping up, and so hfs{plus} will have a maintainer taking care of
it after all.. - Linus ]
- Switch CONFIG_SYSFS_SYCALL default to n and decouple from
CONFIG_EXPERT
- Fix an audit bug caused by changes to our kernel path lookup helpers
this cycle. Audit needs the parent path even if the dentry it tried
to look up is negative
- Ensure that the kernel path lookup helpers leave the passed in path
argument clean when they return an error. This is consistent with all
our other helpers
- Ensure that vfs_getattr_nosec() calls bdev_statx() so the relevant
information is available to kernel consumers as well
- Don't set a timer and call schedule() if the timer will expire
immediately in epoll
- Make netfs lookup tables with __nonstring
* tag 'vfs-6.15-rc3.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
Revert "hfs{plus}: add deprecation warning"
fs: move the bdex_statx call to vfs_getattr_nosec
netfs: Mark __nonstring lookup tables
eventpoll: Set epoll timeout if it's in the future
fs: ensure that *path_locked*() helpers leave passed path pristine
fs: add kern_path_locked_negative()
hfs{plus}: add deprecation warning
Kconfig: switch CONFIG_SYSFS_SYCALL default to n
Pull block fixes from Jens Axboe:
- MD pull via Yu:
- fix raid10 missing discard IO accounting (Yu Kuai)
- fix bitmap stats for bitmap file (Zheng Qixing)
- fix oops while reading all member disks failed during
check/repair (Meir Elisha)
- NVMe pull via Christoph:
- fix scan failure for non-ANA multipath controllers (Hannes
Reinecke)
- fix multipath sysfs links creation for some cases (Hannes
Reinecke)
- PCIe endpoint fixes (Damien Le Moal)
- use NULL instead of 0 in the auth code (Damien Le Moal)
- Various ublk fixes:
- Slew of selftest additions
- Improvements and fixes for IO cancelation
- Tweak to Kconfig verbiage
- Fix for page dirtying for blk integrity mapped pages
- loop fixes:
- buffered IO fix
- uevent fixes
- request priority inheritance fix
- Various little fixes
* tag 'block-6.15-20250417' of git://git.kernel.dk/linux: (38 commits)
selftests: ublk: add generic_06 for covering fault inject
ublk: simplify aborting ublk request
ublk: remove __ublk_quiesce_dev()
ublk: improve detection and handling of ublk server exit
ublk: move device reset into ublk_ch_release()
ublk: rely on ->canceling for dealing with ublk_nosrv_dev_should_queue_io
ublk: add ublk_force_abort_dev()
ublk: properly serialize all FETCH_REQs
selftests: ublk: move creating UBLK_TMP into _prep_test()
selftests: ublk: add test_stress_05.sh
selftests: ublk: support user recovery
selftests: ublk: support target specific command line
selftests: ublk: increase max nr_queues and queue depth
selftests: ublk: set queue pthread's cpu affinity
selftests: ublk: setup ring with IORING_SETUP_SINGLE_ISSUER/IORING_SETUP_DEFER_TASKRUN
selftests: ublk: add two stress tests for zero copy feature
selftests: ublk: run stress tests in parallel
selftests: ublk: make sure _add_ublk_dev can return in sub-shell
selftests: ublk: cleanup backfile automatically
selftests: ublk: add io_uring uapi header
...
Currently bdex_statx is only called from the very high-level
vfs_statx_path function, and thus bypassing it for in-kernel calls
to vfs_getattr or vfs_getattr_nosec.
This breaks querying the block ѕize of the underlying device in the
loop driver and also is a pitfall for any other new kernel caller.
Move the call into the lowest level helper to ensure all callers get
the right results.
Fixes: 2d985f8c6b ("vfs: support STATX_DIOALIGN on block devices")
Fixes: f4774e92aa ("loop: take the file system minimum dio alignment into account")
Reported-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/20250417064042.712140-1-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
Placing multiple protection information buffers inside the same page
can lead to oopses because set_page_dirty_lock() can't be called from
interrupt context.
Since a protection information buffer is not backed by a file there is
no point in setting its page dirty, there is nothing to synchronize.
Drop the call to set_page_dirty_lock() and remove the last argument to
bio_integrity_unpin_bvec().
Cc: stable@vger.kernel.org
Fixes: 492c5d4559 ("block: bio-integrity: directly map user buffers")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/yq1v7r3ev9g.fsf@ca-mkp.ca.oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When registering a queue fails after blk_mq_sysfs_register() is
successful but the function later encounters an error, we need
to clean up the blk_mq_sysfs resources.
Add the missing blk_mq_sysfs_unregister() call in the error path
to properly clean up these resources and prevent a memory leak.
Fixes: 320ae51fee ("blk-mq: new multi-queue block IO queueing mechanism")
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250412092554.475218-1-zhengqixing@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull block updates from Jens Axboe:
- Fixes for integrity handling
- NVMe pull request via Keith:
- Secure concatenation for TCP transport (Hannes)
- Multipath sysfs visibility (Nilay)
- Various cleanups (Qasim, Baruch, Wang, Chen, Mike, Damien, Li)
- Correct use of 64-bit BARs for pci-epf target (Niklas)
- Socket fix for selinux when used in containers (Peijie)
- MD pull request via Yu:
- fix recovery can preempt resync (Li Nan)
- fix md-bitmap IO limit (Su Yue)
- fix raid10 discard with REQ_NOWAIT (Xiao Ni)
- fix raid1 memory leak (Zheng Qixing)
- fix mddev uaf (Yu Kuai)
- fix raid1,raid10 IO flags (Yu Kuai)
- some refactor and cleanup (Yu Kuai)
- Series cleaning up and fixing bugs in the bad block handling code
- Improve support for write failure simulation in null_blk
- Various lock ordering fixes
- Fixes for locking for debugfs attributes
- Various ublk related fixes and improvements
- Cleanups for blk-rq-qos wait handling
- blk-throttle fixes
- Fixes for loop dio and sync handling
- Fixes and cleanups for the auto-PI code
- Block side support for hardware encryption keys in blk-crypto
- Various cleanups and fixes
* tag 'for-6.15/block-20250322' of git://git.kernel.dk/linux: (105 commits)
nvmet: replace max(a, min(b, c)) by clamp(val, lo, hi)
nvme-tcp: fix selinux denied when calling sock_sendmsg
nvmet: pci-epf: Always configure BAR0 as 64-bit
nvmet: Remove duplicate uuid_copy
nvme: zns: Simplify nvme_zone_parse_entry()
nvmet: pci-epf: Remove redundant 'flush_workqueue()' calls
nvmet-fc: Remove unused functions
nvme-pci: remove stale comment
nvme-fc: Utilise min3() to simplify queue count calculation
nvme-multipath: Add visibility for queue-depth io-policy
nvme-multipath: Add visibility for numa io-policy
nvme-multipath: Add visibility for round-robin io-policy
nvmet: add tls_concat and tls_key debugfs entries
nvmet-tcp: support secure channel concatenation
nvmet: Add 'sq' argument to alloc_ctrl_args
nvme-fabrics: reset admin connection for secure concatenation
nvme-tcp: request secure channel concatenation
nvme-keyring: add nvme_tls_psk_refresh()
nvme: add nvme_auth_derive_tls_psk()
nvme: add nvme_auth_generate_digest()
...
Pull CRC updates from Eric Biggers:
"Another set of improvements to the kernel's CRC (cyclic redundancy
check) code:
- Rework the CRC64 library functions to be directly optimized, like
what I did last cycle for the CRC32 and CRC-T10DIF library
functions
- Rewrite the x86 PCLMULQDQ-optimized CRC code, and add VPCLMULQDQ
support and acceleration for crc64_be and crc64_nvme
- Rewrite the riscv Zbc-optimized CRC code, and add acceleration for
crc_t10dif, crc64_be, and crc64_nvme
- Remove crc_t10dif and crc64_rocksoft from the crypto API, since
they are no longer needed there
- Rename crc64_rocksoft to crc64_nvme, as the old name was incorrect
- Add kunit test cases for crc64_nvme and crc7
- Eliminate redundant functions for calculating the Castagnoli CRC32,
settling on just crc32c()
- Remove unnecessary prompts from some of the CRC kconfig options
- Further optimize the x86 crc32c code"
* tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (36 commits)
x86/crc: drop the avx10_256 functions and rename avx10_512 to avx512
lib/crc: remove unnecessary prompt for CONFIG_CRC64
lib/crc: remove unnecessary prompt for CONFIG_LIBCRC32C
lib/crc: remove unnecessary prompt for CONFIG_CRC8
lib/crc: remove unnecessary prompt for CONFIG_CRC7
lib/crc: remove unnecessary prompt for CONFIG_CRC4
lib/crc7: unexport crc7_be_syndrome_table
lib/crc_kunit.c: update comment in crc_benchmark()
lib/crc_kunit.c: add test and benchmark for crc7_be()
x86/crc32: optimize tail handling for crc32c short inputs
riscv/crc64: add Zbc optimized CRC64 functions
riscv/crc-t10dif: add Zbc optimized CRC-T10DIF function
riscv/crc32: reimplement the CRC32 functions using new template
riscv/crc: add "template" for Zbc optimized CRC functions
x86/crc: add ANNOTATE_NOENDBR to suppress objtool warnings
x86/crc32: improve crc32c_arch() code generation with clang
x86/crc64: implement crc64_be and crc64_nvme using new template
x86/crc-t10dif: implement crc_t10dif using new template
x86/crc32: implement crc32_le using new template
x86/crc: add "template" for [V]PCLMULQDQ based CRC functions
...
Pull timer cleanups from Thomas Gleixner:
"A treewide hrtimer timer cleanup
hrtimers are initialized with hrtimer_init() and a subsequent store to
the callback pointer. This turned out to be suboptimal for the
upcoming Rust integration and is obviously a silly implementation to
begin with.
This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
with hrtimer_setup(T, cb);
The conversion was done with Coccinelle and a few manual fixups.
Once the conversion has completely landed in mainline, hrtimer_init()
will be removed and the hrtimer::function becomes a private member"
* tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
wifi: rt2x00: Switch to use hrtimer_update_function()
io_uring: Use helper function hrtimer_update_function()
serial: xilinx_uartps: Use helper function hrtimer_update_function()
ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup()
RDMA: Switch to use hrtimer_setup()
virtio: mem: Switch to use hrtimer_setup()
drm/vmwgfx: Switch to use hrtimer_setup()
drm/xe/oa: Switch to use hrtimer_setup()
drm/vkms: Switch to use hrtimer_setup()
drm/msm: Switch to use hrtimer_setup()
drm/i915/request: Switch to use hrtimer_setup()
drm/i915/uncore: Switch to use hrtimer_setup()
drm/i915/pmu: Switch to use hrtimer_setup()
drm/i915/perf: Switch to use hrtimer_setup()
drm/i915/gvt: Switch to use hrtimer_setup()
drm/i915/huc: Switch to use hrtimer_setup()
drm/amdgpu: Switch to use hrtimer_setup()
stm class: heartbeat: Switch to use hrtimer_setup()
i2c: Switch to use hrtimer_setup()
iio: Switch to use hrtimer_setup()
...
Pull cgroup updates from Tejun Heo:
- Add deprecation info messages to cgroup1-only features
- rstat updates including a bug fix and breaking up a critical section
to reduce interrupt latency impact
- Other misc and doc updates
* tag 'cgroup-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: rstat: Cleanup flushing functions and locking
cgroup/rstat: avoid disabling irqs for O(num_cpu)
mm: Fix a build breakage in memcontrol-v1.c
blk-cgroup: Simplify policy files registration
cgroup: Update file naming comment
cgroup: Add deprecation message to legacy freezer controller
mm: Add transformation message for per-memcg swappiness
RFC cgroup/cpuset-v1: Add deprecation messages to sched_relax_domain_level
cgroup/cpuset-v1: Add deprecation messages to memory_migrate
cgroup/cpuset-v1: Add deprecation messages to mem_exclusive and mem_hardwall
cgroup: Print message when /proc/cgroups is read on v2-only system
cgroup/blkio: Add deprecation messages to reset_stats
cgroup/cpuset-v1: Add deprecation messages to memory_spread_page and memory_spread_slab
cgroup/cpuset-v1: Add deprecation messages to sched_load_balance and memory_pressure_enabled
cgroup, docs: Be explicit about independence of RT_GROUP_SCHED and non-cpu controllers
cgroup/rstat: Fix forceidle time in cpu.stat
cgroup/misc: Remove unused misc_cg_res_total_usage
cgroup/cpuset: Move procfs cpuset attribute under cgroup-v1.c
cgroup: update comment about dropping cgroup kn refs
Pull vfs pagesize updates from Christian Brauner:
"This enables block sizes greater than the page size for block devices.
With this we can start supporting block devices with logical block
sizes larger than 4k.
It also allows to lift the device cache sector size support to 64k.
This allows filesystems which can use larger sector sizes up to 64k to
ensure that the filesystem will not generate writes that are smaller
than the specified sector size"
* tag 'vfs-6.15-rc1.pagesize' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
bdev: add back PAGE_SIZE block size validation for sb_set_blocksize()
bdev: use bdev_io_min() for statx block size
block/bdev: lift block size restrictions to 64k
block/bdev: enable large folio support for large logical block sizes
fs/buffer fs/mpage: remove large folio restriction
fs/mpage: use blocks_per_folio instead of blocks_per_page
fs/mpage: avoid negative shift for large blocksize
fs/buffer: remove batching from async read
fs/buffer: simplify block_read_full_folio() with bh_offset()
The commit '245618f8e45f ("block: protect wbt_lat_usec using q->
elevator_lock")' introduced q->elevator_lock to protect updates
to blk-wbt parameters when writing to the sysfs attribute wbt_
lat_usec and the cgroup attribute io.cost.qos. However, both
these attributes also acquire q->rq_qos_mutex, leading to the
following lockdep warning:
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc5+ #138 Not tainted
------------------------------------------------------
bash/5902 is trying to acquire lock:
c000000085d495a0 (&q->rq_qos_mutex){+.+.}-{4:4}, at: wbt_init+0x164/0x238
but task is already holding lock:
c000000085d498c8 (&q->elevator_lock){+.+.}-{4:4}, at: queue_wb_lat_store+0xb0/0x20c
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&q->elevator_lock){+.+.}-{4:4}:
__mutex_lock+0xf0/0xa58
ioc_qos_write+0x16c/0x85c
cgroup_file_write+0xc4/0x32c
kernfs_fop_write_iter+0x1b8/0x29c
vfs_write+0x410/0x584
ksys_write+0x84/0x140
system_call_exception+0x134/0x360
system_call_vectored_common+0x15c/0x2ec
-> #0 (&q->rq_qos_mutex){+.+.}-{4:4}:
__lock_acquire+0x1b6c/0x2ae0
lock_acquire+0x140/0x430
__mutex_lock+0xf0/0xa58
wbt_init+0x164/0x238
queue_wb_lat_store+0x1dc/0x20c
queue_attr_store+0x12c/0x164
sysfs_kf_write+0x6c/0xb0
kernfs_fop_write_iter+0x1b8/0x29c
vfs_write+0x410/0x584
ksys_write+0x84/0x140
system_call_exception+0x134/0x360
system_call_vectored_common+0x15c/0x2ec
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&q->elevator_lock);
lock(&q->rq_qos_mutex);
lock(&q->elevator_lock);
lock(&q->rq_qos_mutex);
*** DEADLOCK ***
6 locks held by bash/5902:
#0: c000000051122400 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x84/0x140
#1: c00000007383f088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x174/0x29c
#2: c000000008550428 (kn->active#182){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x180/0x29c
#3: c000000085d493a8 (&q->q_usage_counter(io)#5){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x28/0x40
#4: c000000085d493e0 (&q->q_usage_counter(queue)#5){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x28/0x40
#5: c000000085d498c8 (&q->elevator_lock){+.+.}-{4:4}, at: queue_wb_lat_store+0xb0/0x20c
stack backtrace:
CPU: 17 UID: 0 PID: 5902 Comm: bash Kdump: loaded Not tainted 6.14.0-rc5+ #138
Hardware name: IBM,9043-MRX POWER10 (architected) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_028) hv:phyp pSeries
Call Trace:
[c0000000721ef590] [c00000000118f8a8] dump_stack_lvl+0x108/0x18c (unreliable)
[c0000000721ef5c0] [c00000000022563c] print_circular_bug+0x448/0x604
[c0000000721ef670] [c000000000225a44] check_noncircular+0x24c/0x26c
[c0000000721ef740] [c00000000022bf28] __lock_acquire+0x1b6c/0x2ae0
[c0000000721ef870] [c000000000229240] lock_acquire+0x140/0x430
[c0000000721ef970] [c0000000011cfbec] __mutex_lock+0xf0/0xa58
[c0000000721efaa0] [c00000000096c46c] wbt_init+0x164/0x238
[c0000000721efaf0] [c0000000008f8cd8] queue_wb_lat_store+0x1dc/0x20c
[c0000000721efb50] [c0000000008f8fa0] queue_attr_store+0x12c/0x164
[c0000000721efc60] [c0000000007c11cc] sysfs_kf_write+0x6c/0xb0
[c0000000721efca0] [c0000000007bfa4c] kernfs_fop_write_iter+0x1b8/0x29c
[c0000000721efcf0] [c0000000006a281c] vfs_write+0x410/0x584
[c0000000721efdc0] [c0000000006a2cc8] ksys_write+0x84/0x140
[c0000000721efe10] [c000000000031b64] system_call_exception+0x134/0x360
[c0000000721efe50] [c00000000000cedc] system_call_vectored_common+0x15c/0x2ec
>From the above log it's apparent that method which writes to sysfs attr
wbt_lat_usec acquires q->elevator_lock first, and then acquires q->rq_
qos_mutex. However the another method which writes to io.cost.qos,
acquires q->rq_qos_mutex first, and then acquires q->rq_qos_mutex. So
this could potentially cause the deadlock.
A closer look at ioc_qos_write shows that correcting the lock order is
non-trivial because q->rq_qos_mutex is acquired in blkg_conf_open_bdev
and released in blkg_conf_exit. The function blkg_conf_open_bdev is
responsible for parsing user input and finding the corresponding block
device (bdev) from the user provided major:minor number.
Since we do not know the bdev until blkg_conf_open_bdev completes, we
cannot simply move q->elevator_lock acquisition before blkg_conf_open_
bdev. So to address this, we intoduce new helpers blkg_conf_open_bdev_
frozen and blkg_conf_exit_frozen which are just wrappers around blkg_
conf_open_bdev and blkg_conf_exit respectively. The helper blkg_conf_
open_bdev_frozen is similar to blkg_conf_open_bdev, but additionally
freezes the queue, acquires q->elevator_lock and ensures the correct
locking order is followed between q->elevator_lock and q->rq_qos_mutex.
Similarly another helper blkg_conf_exit_frozen in addition to unfreezing
the queue ensures that we release the locks in correct order.
By using these helpers, now we maintain the same locking order in all
code paths where we update blk-wbt parameters.
Fixes: 245618f8e4 ("block: protect wbt_lat_usec using q->elevator_lock")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202503171650.cc082b66-lkp@intel.com
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250319105518.468941-3-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch improve the returned error code of blkcg_policy_register().
1. Move the validation check for cpd/pd_alloc_fn and cpd/pd_free_fn
function pairs to the start of blkcg_policy_register(). This ensures
we immediately return -EINVAL if the function pairs are not correctly
provided, rather than returning -ENOSPC after locking and unlocking
mutexes unnecessarily.
Those locks should not contention any problems, as error of policy
registration is a super cold path.
2. Return -ENOMEM when cpd_alloc_fn() failed.
Co-authored-by: Wen Tao <wentao@uniontech.com>
Signed-off-by: Wen Tao <wentao@uniontech.com>
Signed-off-by: Chen Linxuan <chenlinxuan@uniontech.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/3E333A73B6B6DFC0+20250317022924.150907-1-chenlinxuan@uniontech.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The hctx_busy_show method in debugfs is currently unprotected. This
method iterates over all started requests in a tagset and prints them.
However, the tags can be updated concurrently via the sysfs attributes
'nr_requests' or 'scheduler' (elevator switch), leading to potential
race conditions.
Since sysfs attributes 'nr_requests' and 'scheduler' are already
protected using q->elevator_lock, extend this protection to the debugfs
'busy' attribute as well to ensure consistency.
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250313115235.3707600-4-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In some debugfs attribute read methods, failure to acquire the mutex
lock results in jumping to a label before returning an error code.
However this is unnecessary, as we can return the failure code directly,
improving code readability and reducing complexity.
This commit removes the goto labels and ensures that the method returns
immediately upon failing to acquire the mutex lock.
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250313115235.3707600-3-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, the block debugfs attributes (tags, tags_bitmap, sched_tags,
and sched_tags_bitmap) are protected using q->sysfs_lock. However, these
attributes are updated in multiple scenarios:
- During driver probe method
- During an elevator switch/update
- During an nr_hw_queues update
- When writing to the sysfs attribute nr_requests
All these update paths (except driver probe method, which doesn't
require any protection) are already protected using q->elevator_lock. To
ensure consistency and proper synchronization, replace q->sysfs_lock
with q->elevator_lock for protecting these debugfs attributes.
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250313115235.3707600-2-nilay@linux.ibm.com
[axboe: some commit message rewording/fixes]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use one set of files when there is no difference between default and
legacy files, similar to regular subsys files registration. No
functional change.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tejun Heo <tj@kernel.org>
It is difficult to sync with stat updaters, stats are (should be)
monotonic so users can calculate differences from a reference.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tejun Heo <tj@kernel.org>
Currently, hctx attributes (nr_tags, nr_reserved_tags, and cpu_list)
are protected using `q->sysfs_lock`. However, these attributes can be
updated in multiple scenarios:
- During the driver's probe method.
- When updating nr_hw_queues.
- When writing to the sysfs attribute nr_requests,
which can modify nr_tags.
The nr_requests attribute is already protected using q->elevator_lock,
but none of the update paths actually use q->sysfs_lock to protect hctx
attributes. So to ensure proper synchronization, replace q->sysfs_lock
with q->elevator_lock when reading hctx attributes through sysfs.
Additionally, blk_mq_update_nr_hw_queues allocates and updates hctx.
The allocation of hctx is protected using q->elevator_lock, however,
updating hctx params happens without any protection, so safeguard hctx
param update path by also using q->elevator_lock.
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250306093956.2818808-1-nilay@linux.ibm.com
[axboe: wrap comment at 80 chars]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The wbt latency and state could be updated while initializing the
elevator or exiting the elevator. It could be also updated while
configuring IO latency QoS parameters using cgroup. The elevator
code path is now protected with q->elevator_lock. So we should
protect the access to sysfs attribute wbt_lat_usec using q->elevator
_lock instead of q->sysfs_lock. White we're at it, also protect
ioc_qos_write(), which configures wbt parameters via cgroup, using
q->elevator_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-7-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The sysfs attribute nr_requests could be simultaneously updated from
elevator switch/update or nr_hw_queue update code path. The update to
nr_requests for each of those code paths runs holding q->elevator_lock.
So we should protect access to sysfs attribute nr_requests using q->
elevator_lock instead of q->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-6-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A queue's elevator can be updated either when modifying nr_hw_queues
or through the sysfs scheduler attribute. Currently, elevator switching/
updating is protected using q->sysfs_lock, but this has led to lockdep
splats[1] due to inconsistent lock ordering between q->sysfs_lock and
the freeze-lock in multiple block layer call sites.
As the scope of q->sysfs_lock is not well-defined, its (mis)use has
resulted in numerous lockdep warnings. To address this, introduce a new
q->elevator_lock, dedicated specifically for protecting elevator
switches/updates. And we'd now use this new q->elevator_lock instead of
q->sysfs_lock for protecting elevator switches/updates.
While at it, make elv_iosched_load_module() a static function, as it is
only called from elv_iosched_store(). Also, remove redundant parameters
from elv_iosched_load_module() function signature.
[1] https://lore.kernel.org/all/67637e70.050a0220.3157ee.000c.GAE@google.com/
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-5-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There're few sysfs attributes in block layer which don't really need
acquiring q->sysfs_lock while accessing it. The reason being, reading/
writing a value from/to such attributes are either atomic or could be
easily protected using READ_ONCE()/WRITE_ONCE(). Moreover, sysfs
attributes are inherently protected with sysfs/kernfs internal locking.
So this change help segregate all existing sysfs attributes for which
we could avoid acquiring q->sysfs_lock. For all read-only attributes
we removed the q->sysfs_lock from show method of such attributes. In
case attribute is read/write then we removed the q->sysfs_lock from
both show and store methods of these attributes.
We audited all block sysfs attributes and found following list of
attributes which shouldn't require q->sysfs_lock protection:
1. io_poll:
Write to this attribute is ignored. So, we don't need q->sysfs_lock.
2. io_poll_delay:
Write to this attribute is NOP, so we don't need q->sysfs_lock.
3. io_timeout:
Write to this attribute updates q->rq_timeout and read of this
attribute returns the value stored in q->rq_timeout Moreover, the
q->rq_timeout is set only once when we init the queue (under blk_mq_
init_allocated_queue()) even before disk is added. So that means
that we don't need to protect it with q->sysfs_lock. As this
attribute is not directly correlated with anything else simply using
READ_ONCE/WRITE_ONCE should be enough.
4. nomerges:
Write to this attribute file updates two q->flags : QUEUE_FLAG_
NOMERGES and QUEUE_FLAG_NOXMERGES. These flags are accessed during
bio-merge which anyways doesn't run with q->sysfs_lock held.
Moreover, the q->flags are updated/accessed with bitops which are
atomic. So, protecting it with q->sysfs_lock is not necessary.
5. rq_affinity:
Write to this attribute file makes atomic updates to q->flags:
QUEUE_FLAG_SAME_COMP and QUEUE_FLAG_SAME_FORCE. These flags are
also accessed from blk_mq_complete_need_ipi() using test_bit macro.
As read/write to q->flags uses bitops which are atomic, protecting
it with q->stsys_lock is not necessary.
6. nr_zones:
Write to this attribute happens in the driver probe method (except
nvme) before disk is added and outside of q->sysfs_lock or any other
lock. Moreover nr_zones is defined as "unsigned int" and so reading
this attribute, even when it's simultaneously being updated on other
cpu, should not return torn value on any architecture supported by
linux. So we can avoid using q->sysfs_lock or any other lock/
protection while reading this attribute.
7. discard_zeroes_data:
Reading of this attribute always returns 0, so we don't require
holding q->sysfs_lock.
8. write_same_max_bytes
Reading of this attribute always returns 0, so we don't require
holding q->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-4-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation to further simplify and group sysfs attributes which
don't require locking or require some form of locking other than q->
limits_lock, move acquire/release of q->sysfs_lock and queue freeze/
unfreeze under each attributes' respective show/store method.
While we are at it, also remove ->load_module() as it's used to load
the module before queue is freezed. Now as we moved queue-freeze under
->store(), we could load module directly from the attributes' store
method before we actually start freezing the queue. Currently, the
->load_module() is only used by "scheduler" attribute, so we now load
the relevant elevator module before we start freezing the queue in
elv_iosched_store().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-3-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There're few sysfs attributes(RW) whose store method is protected
with q->limits_lock, however the corresponding show method of these
attributes run holding q->sysfs_lock and that doesn't make sense
as ideally the show method of these attributes should also run
holding q->limits_lock instead of q->sysfs_lock. Hence update the
show method of these sysfs attributes so that reading of these
attributes acquire q->limits_lock instead of q->sysfs_lock.
Similarly, there're few sysfs attributes(RO) whose show method is
currently protected with q->sysfs_lock however updates to these
attributes could occur using atomic limit update APIs such as queue_
limits_start_update() and queue_limits_commit_update() which run
holding q->limits_lock. So that means that reading these attributes
holding q->sysfs_lock doesn't make sense. Hence update the show method
of these sysfs attributes(RO) such that they run with holding q->
limits_lock instead of q->sysfs_lock.
We have defined a new macro QUEUE_LIM_RO_ENTRY() which uses new ->show_
limit() method and it runs holding q->limits_lock. All existing sysfs
attributes(RO) which needs protection using q->limits_lock while
reading have been now updated to use this new macro for initialization.
Also, the existing QUEUE_LIM_RW_ENTRY() is updated to use new ->show_
limit() method for reading attributes instead of existing ->show()
method. As ->show_limit() runs holding q->limits_lock, the existing
sysfs attributes(RW) requiring protection are now inherently protected
using q->limits_lock instead of q->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-2-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block fixes from Jens Axboe:
- NVMe pull request via Keith:
- TCP use after free fix on polling (Sagi)
- Controller memory buffer cleanup fixes (Icenowy)
- Free leaking requests on bad user passthrough commands (Keith)
- TCP error message fix (Maurizio)
- TCP corruption fix on partial PDU (Maurizio)
- TCP memory ordering fix for weakly ordered archs (Meir)
- Type coercion fix on message error for TCP (Dan)
- Name the RQF flags enum, fixing issues with anon enums and BPF import
of it
- ublk parameter setting fix
- GPT partition 7-bit conversion fix
* tag 'block-6.14-20250306' of git://git.kernel.dk/linux:
block: Name the RQF flags enum
nvme-tcp: fix signedness bug in nvme_tcp_init_connection()
block: fix conversion of GPT partition name to 7-bit
ublk: set_params: properly check if parameters can be applied
nvmet-tcp: Fix a possible sporadic response drops in weakly ordered arch
nvme-tcp: fix potential memory corruption in nvme_tcp_recv_pdu()
nvme-tcp: Fix a C2HTermReq error message
nvmet: remove old function prototype
nvme-ioctl: fix leaked requests on mapping error
nvme-pci: skip CMB blocks incompatible with PCI P2P DMA
nvme-pci: clean up CMBMSC when registering CMB fails
nvme-tcp: fix possible UAF in nvme_tcp_poll