commit 86399ea071 upstream.
When BLKRESETZONE ioctl and data read race, the data read leaves stale
page cache. The commit e511350590 ("block: Discard page cache of zone
reset target range") added page cache truncation to avoid stale page
cache after the ioctl. However, the stale page cache still can be read
during the reset zone operation for the ioctl. To avoid the stale page
cache completely, hold invalidate_lock of the block device file mapping.
Fixes: e511350590 ("block: Discard page cache of zone reset target range")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211111085238.942492-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 35e4c6c1a2 upstream.
When BLKZEROOUT ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is modified to call "blkdiscard -z" command
and repeated hundreds of times.
This patch can be applied back to the stable kernel version v5.15.y.
Rework is required for older stable kernels.
Fixes: 22dd6d3566 ("block: invalidate the page cache when issuing BLKZEROOUT")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-3-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7607c44c15 upstream.
When BLKDISCARD ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is repeated hundreds of times.
This patch can be applied back to the stable kernel version v5.15.y
with slight patch edit. Rework is required for older stable kernels.
Fixes: 351499a172 ("block: Invalidate cache on discard v2")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-2-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fe7d064fa3 ]
Commit 83cbce9574 ("block: add error handling for device_add_disk /
add_disk") added error handling to device_add_disk(), however the goto
label for the kobject_create_and_add() failure did not set the return
value correctly, and so we can end up in a situation where
kobject_create_and_add() fails but we report success.
Fixes: 83cbce9574 ("block: add error handling for device_add_disk / add_disk")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211103164023.1384821-1-mcgrof@kernel.org
[axboe: fold in followup fix from Wu Bo <wubo40@huawei.com>]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 037057a5a9 ]
This check is meant to catch cases where a requeue is attempted on a
request that is still inserted. It's never really been useful to catch any
misuse, and now it's actively wrong. Outside of that, this should not be a
BUG_ON() to begin with.
Remove the check as it's now causing active harm, as requeue off the plug
path will trigger it even though the request state is just fine.
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Link: https://lore.kernel.org/linux-block/CAHj4cs80zAUc2grnCZ015-2Rvd-=gXRfB_dFKy=RTm+wRo09HQ@mail.gmail.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ba0ffdd8ce ]
Particularly for NVMe with efficient deferred submission for many
requests, there are nice benefits to be seen by bumping the default max
plug count from 16 to 32. This is especially true for virtualized setups,
where the submit part is more expensive. But can be noticed even on
native hardware.
Reduce the multiple queue factor from 4 to 2, since we're changing the
default size.
While changing it, move the defines into the block layer private header.
These aren't values that anyone outside of the block layer uses, or
should use.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Commit a33df75c63 ("block: use an xarray for disk->part_tbl") modified
the method to check partition existence in host-aware zoned block
devices from disk_has_partitions() helper function call to empty check
of xarray disk->part_tbl. However, disk->part_tbl always has single
entry for disk->part0 and never becomes empty. This resulted in the
host-aware zoned devices always judged to have partitions, and it made
the sysfs queue/zoned attribute to be "none" instead of "host-aware"
regardless of partition existence in the devices.
This also caused DEBUG_LOCKS_WARN_ON(lock->magic != lock) for
sdkp->rev_mutex in scsi layer when the kernel detects host-aware zoned
device. Since block layer handled the host-aware zoned devices as non-
zoned devices, scsi layer did not have chance to initialize the mutex
for zone revalidation. Therefore, the warning was triggered.
To fix the issues, call the helper function disk_has_partitions() in
place of disk->part_tbl empty check. Since the function was removed with
the commit a33df75c63, reimplement it to walk through entries in the
xarray disk->part_tbl.
Fixes: a33df75c63 ("block: use an xarray for disk->part_tbl")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.14+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211026060115.753746-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When dispatching a zone append write request to a SCSI zoned block device,
if the target zone of the request is already locked, the device driver will
return BLK_STS_ZONE_RESOURCE and the request will be pushed back to the
hctx dipatch queue. The queue will be marked as RESTART in
dd_finish_request() and restarted in __blk_mq_free_request(). However, this
restart applies to the hctx of the completed request. If the requeued
request is on a different hctx, dispatch will no be retried until another
request is submitted or the next periodic queue run triggers, leading to up
to 30 seconds latency for the requeued request.
Fix this problem by scheduling a queue restart similarly to the
BLK_STS_RESOURCE case or when we cannot get the budget.
Also, consolidate the checks into the "need_resource" variable to simplify
the condition.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Niklas Cassel <Niklas.Cassel@wdc.com>
Link: https://lore.kernel.org/r/20211026165127.4151055-1-naohiro.aota@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Before removing disk from sysfs, userspace still may change queue via
sysfs, such as switching elevator or setting wbt latency, both may
reinitialize wbt, then the warning in blk_free_queue_stats() will be
triggered since rq_qos_exit() is moved to del_gendisk().
Fixes the issue by moving draining queue & tearing down after disk is
removed from sysfs, at that time no one can come into queue's
store()/show().
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Fixes: 8e141f9eb8 ("block: drain file system I/O on del_gendisk")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211026101204.2897166-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=uhGw
-----END PGP SIGNATURE-----
Merge tag 'block-5.15-2021-10-22' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Fix for the cgroup code not ussing irq safe stats updates, and one fix
for an error handling condition in add_partition()"
* tag 'block-5.15-2021-10-22' of git://git.kernel.dk/linux-block:
block: fix incorrect references to disk objects
blk-cgroup: blk_cgroup_bio_start() should use irq-safe operations on blkg->iostat_cpu
When adding partitions to the disk, the reference count of the disk
object is increased. then alloc partition device and called
device_add(), if the device_add() return error, the reference
count of the disk object will be reduced twice, at put_device(pdev)
and put_disk(disk). this leads to the end of the object's life cycle
prematurely, and trigger following calltrace.
__init_work+0x2d/0x50 kernel/workqueue.c:519
synchronize_rcu_expedited+0x3af/0x650 kernel/rcu/tree_exp.h:847
bdi_remove_from_list mm/backing-dev.c:938 [inline]
bdi_unregister+0x17f/0x5c0 mm/backing-dev.c:946
release_bdi+0xa1/0xc0 mm/backing-dev.c:968
kref_put include/linux/kref.h:65 [inline]
bdi_put+0x72/0xa0 mm/backing-dev.c:976
bdev_free_inode+0x11e/0x220 block/bdev.c:408
i_callback+0x3f/0x70 fs/inode.c:226
rcu_do_batch kernel/rcu/tree.c:2508 [inline]
rcu_core+0x76d/0x16c0 kernel/rcu/tree.c:2743
__do_softirq+0x1d7/0x93b kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu kernel/softirq.c:636 [inline]
irq_exit_rcu+0xf2/0x130 kernel/softirq.c:648
sysvec_apic_timer_interrupt+0x93/0xc0
making disk is NULL when calling put_disk().
Reported-by: Hao Sun <sunhao.th@gmail.com>
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211018103422.2043-1-qiang.zhang1211@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=J/e4
-----END PGP SIGNATURE-----
Merge tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Bigger than usual for this point in time, the majority is fixing some
issues around BDI lifetimes with the move from the request_queue to
the disk in this release. In detail:
- Series on draining fs IO for del_gendisk() (Christoph)
- NVMe pull request via Christoph:
- fix the abort command id (Keith Busch)
- nvme: fix per-namespace chardev deletion (Adam Manzanares)
- brd locking scope fix (Tetsuo)
- BFQ fix (Paolo)"
* tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
block, bfq: reset last_bfqq_created on group change
block: warn when putting the final reference on a registered disk
brd: reduce the brd_devices_mutex scope
kyber: avoid q->disk dereferences in trace points
block: keep q_usage_counter in atomic mode after del_gendisk
block: drain file system I/O on del_gendisk
block: split bio_queue_enter from blk_queue_enter
block: factor out a blk_try_enter_queue helper
block: call submit_bio_checks under q_usage_counter
nvme: fix per-namespace chardev deletion
block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
nvme-pci: Fix abort command id
Since commit 430a67f9d6 ("block, bfq: merge bursts of newly-created
queues"), BFQ maintains a per-group pointer to the last bfq_queue
created. If such a queue, say bfqq, happens to move to a different
group, then bfqq is no more a valid last bfq_queue created for its
previous group. That pointer must then be cleared. Not resetting such
a pointer may also cause UAF, if bfqq happens to also be freed after
being moved to a different group. This commit performs this missing
reset. As such it fixes commit 430a67f9d6 ("block, bfq: merge bursts
of newly-created queues").
Such a missing reset is most likely the cause of the crash reported in [1].
With some analysis, we found that this crash was due to the
above UAF. And such UAF did go away with this commit applied [1].
Anyway, before this commit, that crash happened to be triggered in
conjunction with commit 2d52c58b9c ("block, bfq: honor already-setup
queue merges"). The latter was then reverted by commit ebc69e897e
("Revert "block, bfq: honor already-setup queue merges""). Yet commit
2d52c58b9c ("block, bfq: honor already-setup queue merges") contains
no error related with the above UAF, and can then be restored.
[1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Fixes: 430a67f9d6 ("block, bfq: merge bursts of newly-created queues")
Tested-by: Grzegorz Kowal <custos.mentis@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20211015144336.45894-2-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Warn when the last reference on a live disk is put without calling
del_gendisk first. There are some BDI related bug reports that look
like a case of this, so make sure we have the proper instrumentation
to catch it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211014130231.1468538-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
q->disk becomes invalid after the gendisk is removed. Work around this
by caching the dev_t for the tracepoints. The real fix would be to
properly tear down the I/O schedulers with the gendisk, but that is
a much more invasive change.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211012093301.GA27795@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't switch back to percpu mode to avoid the double RCU grace period
when tearing down SCSI devices. After removing the disk only passthrough
commands can be send anyway.
Suggested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-6-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of delaying draining of file system I/O related items like the
blk-qos queues, the integrity read workqueue and timeouts only when the
request_queue is removed, do that when del_gendisk is called. This is
important for SCSI where the upper level drivers that control the gendisk
are separate entities, and the disk can be freed much earlier than the
request_queue, or can even be unbound without tearing down the queue.
Fixes: edb0872f44 ("block: move the bdi from the request_queue to the gendisk")
Reported-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-5-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To prepare for fixing a gendisk shutdown race, open code the
blk_queue_enter logic in bio_queue_enter. This also removes the
pointless flags translation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-4-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Factor out the code to try to get q_usage_counter without blocking into
a separate helper. Both to improve code readability and to prepare for
splitting bio_queue_enter from blk_queue_enter.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20210929071241.934472-3-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ensure all bios check the current values of the queue under freeze
protection, i.e. to make sure the zero capacity set by del_gendisk
is actually seen before dispatching to the driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210929071241.934472-2-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While debugging an issue we've found that $DEBUGFS/block/$disk/state
doesn't decode QUEUE_FLAG_HCTX_ACTIVE but only displays its numerical
value.
Add QUEUE_FLAG(HCTX_ACTIVE) to the blk_queue_flag_name array so it'll get
decoded properly.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/4351076388918075bd80ef07756f9d2ce63be12c.1633332053.git.johannes.thumshirn@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=SMoX
-----END PGP SIGNATURE-----
Merge tag 'block-5.15-2021-10-01' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A few block fixes for this release:
- Revert a BFQ commit that causes breakage for people. Unfortunately
it was auto-selected for stable as well, so now 5.14.7 suffers from
it too. Hopefully stable will pick up this revert quickly too, so
we can remove the issue on that end as well.
- Add a quirk for Apple NVMe controllers, which due to their
non-compliance broke due to the introduction of command sequences
(Keith)
- Use shifts in nbd, fixing a __divdi3 issue (Nick)"
* tag 'block-5.15-2021-10-01' of git://git.kernel.dk/linux-block:
nbd: use shifts rather than multiplies
Revert "block, bfq: honor already-setup queue merges"
nvme: add command id quirk for apple controllers
syzbot is reporting use-after-free read at bdev_free_inode() [1], for
kfree() from __alloc_disk_node() is called before bdev_free_inode()
(which is called after RCU grace period) reads bdev->bd_disk and calls
kfree(bdev->bd_disk).
Fix use-after-free read followed by double kfree() problem
by making sure that bdev->bd_disk is NULL when calling iput().
Link: https://syzkaller.appspot.com/bug?extid=8281086e8a6fbfbd952a [1]
Reported-by: syzbot <syzbot+8281086e8a6fbfbd952a@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/e6dd13c5-8db0-4392-6e78-a42ee5d2a1c4@i-love.sakura.ne.jp
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 2d52c58b9c.
We have had several folks complain that this causes hangs for them, which
is especially problematic as the commit has also hit stable already.
As no resolution seems to be forthcoming right now, revert the patch.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214503
Fixes: 2d52c58b9c ("block, bfq: honor already-setup queue merges")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Thirty Three fixes, I'm afraid. Essentially the build up from the
last couple of weeks while I've been dealling with Linux Plumbers
conference infrastructure issues. It's mostly the usual assortment of
spelling fixes and minor corrections. The only core relevant changes
are to the sd driver to reduce the spin up message spew and fix a
small memory leak on the freeing path.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
-----BEGIN PGP SIGNATURE-----
iJsEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCYU+VfiYcamFtZXMuYm90
dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pishVuMAP9Y2+rE
AyQ3Y9dubie/AyKQ/2ZEFO/G2wz+jEJvfppXJwD4ulhhDFh/l4iNPVa7GW9M/ti3
gd+6gMzzRC9/B+u2gQ==
=+K+l
-----END PGP SIGNATURE-----
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Thirty-three fixes, I'm afraid.
Essentially the build up from the last couple of weeks while I've been
dealling with Linux Plumbers conference infrastructure issues. It's
mostly the usual assortment of spelling fixes and minor corrections.
The only core relevant changes are to the sd driver to reduce the spin
up message spew and fix a small memory leak on the freeing path"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (33 commits)
scsi: ses: Retry failed Send/Receive Diagnostic commands
scsi: target: Fix spelling mistake "CONFLIFT" -> "CONFLICT"
scsi: lpfc: Fix gcc -Wstringop-overread warning, again
scsi: lpfc: Use correct scnprintf() limit
scsi: lpfc: Fix sprintf() overflow in lpfc_display_fpin_wwpn()
scsi: core: Remove 'current_tag'
scsi: acornscsi: Remove tagged queuing vestiges
scsi: fas216: Kill scmd->tag
scsi: qla2xxx: Restore initiator in dual mode
scsi: ufs: core: Unbreak the reset handler
scsi: sd_zbc: Support disks with more than 2**32 logical blocks
scsi: ufs: core: Revert "scsi: ufs: Synchronize SCSI and UFS error handling"
scsi: bsg: Fix device unregistration
scsi: sd: Make sd_spinup_disk() less noisy
scsi: ufs: ufs-pci: Fix Intel LKF link stability
scsi: mpt3sas: Clean up some inconsistent indenting
scsi: megaraid: Clean up some inconsistent indenting
scsi: sr: Fix spelling mistake "does'nt" -> "doesn't"
scsi: Remove SCSI CDROM MAINTAINERS entry
scsi: megaraid: Fix Coccinelle warning
...
When running ->fallocate(), blkdev_fallocate() should hold
mapping->invalidate_lock to prevent page cache from being accessed,
otherwise stale data may be read in page cache.
Without this patch, blktests block/009 fails sometimes. With this patch,
block/009 can pass always.
Also as Jan pointed out, no pages can be created in the discarded area
while you are holding the invalidate_lock, so remove the 2nd
truncate_bdev_range().
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210923023751.1441091-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
rq_qos framework is only applied on request based driver, so:
1) rq_qos_done_bio() needn't to be called for bio based driver
2) rq_qos_done_bio() needn't to be called for bio which isn't tracked,
such as bios ended from error handling code.
Especially in bio_endio():
1) request queue is referred via bio->bi_bdev->bd_disk->queue, which
may be gone since request queue refcount may not be held in above two
cases
2) q->rq_qos may be freed in blk_cleanup_queue() when calling into
__rq_qos_done_bio()
Fix the potential kernel panic by not calling rq_qos_ops->done_bio if
the bio isn't tracked. This way is safe because both ioc_rqos_done_bio()
and blkcg_iolatency_done_bio() are nop if the bio isn't tracked.
Reported-by: Yu Kuai <yukuai3@huawei.com>
Cc: tj@kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20210924110704.1541818-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When the integrity profile is unregistered there can still be integrity
reads queued up which could see a NULL verify_fn as shown by the race
window below:
CPU0 CPU1
process_one_work nvme_validate_ns
bio_integrity_verify_fn nvme_update_ns_info
nvme_update_disk_info
blk_integrity_unregister
---set queue->integrity as 0
bio_integrity_process
--access bi->profile->verify_fn(bi is a pointer of queue->integity)
Before calling blk_integrity_unregister in nvme_update_disk_info, we must
make sure that there is no work item in the kintegrityd_wq. Just call
blk_flush_integrity to flush the work queue so the bug can be resolved.
Signed-off-by: Lihong Kou <koulihong@huawei.com>
[hch: split up and shortened the changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20210914070657.87677-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While clearing the profile itself is harmless, we really should not clear
the stable writes flag if it wasn't set due to a registered integrity
profile.
Reported-by: Lihong Kou <koulihong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20210914070657.87677-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
device_initialize() is used to take a refcount on the device. However,
put_device() is not called during device teardown. This leads to a
leak of private data of the driver core, dev_name(), etc. This is
reported by kmemleak at boot time if we compile kernel with
DEBUG_TEST_DRIVER_REMOVE.
Fix memory leaks during unregistration and implement a release
function.
Link: https://lore.kernel.org/r/20210911105306.1511-1-yuzenghui@huawei.com
Fixes: ead09dd3ae ("scsi: bsg: Simplify device registration")
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
blk-mq can't run allocating driver tag and updating ->rqs[tag]
atomically, meantime blk-mq doesn't clear ->rqs[tag] after the driver
tag is released.
So there is chance to iterating over one stale request just after the
tag is allocated and before updating ->rqs[tag].
scsi_host_busy_iter() calls scsi_host_check_in_flight() to count scsi
in-flight requests after scsi host is blocked, so no new scsi command can
be marked as SCMD_STATE_INFLIGHT. However, driver tag allocation still can
be run by blk-mq core. One request is marked as SCMD_STATE_INFLIGHT,
but this request may have been kept in another slot of ->rqs[], meantime
the slot can be allocated out but ->rqs[] isn't updated yet. Then this
in-flight request is counted twice as SCMD_STATE_INFLIGHT. This way causes
trouble in handling scsi error.
Fixes the issue by not iterating over stale request.
Cc: linux-scsi@vger.kernel.org
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Reported-by: luojiaxing <luojiaxing@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210906065003.439019-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=1ajD
-----END PGP SIGNATURE-----
Merge tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- NVMe pull request from Christoph:
- fix nvmet command set reporting for passthrough controllers (Adam Manzanares)
- update a MAINTAINERS email address (Chaitanya Kulkarni)
- set QUEUE_FLAG_NOWAIT for nvme-multipth (me)
- handle errors from add_disk() (Luis Chamberlain)
- update the keep alive interval when kato is modified (Tatsuya Sasaki)
- fix a buffer overrun in nvmet_subsys_attr_serial (Hannes Reinecke)
- do not reset transport on data digest errors in nvme-tcp (Daniel Wagner)
- only call synchronize_srcu when clearing current path (Daniel Wagner)
- revalidate paths during rescan (Hannes Reinecke)
- Split out the fs/block_dev into block/fops.c and block/bdev.c, which
has been long overdue. Do this now before -rc1, to avoid annoying
conflicts due to this (Christoph)
- blk-throtl use-after-free fix (Li)
- Improve plug depth for multi-device plugs, greatly increasing md
resync performance (Song)
- blkdev_show() locking fix (Tetsuo)
- n64cart error check fix (Yang)
* tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-block:
n64cart: fix return value check in n64cart_probe()
blk-mq: allow 4x BLK_MAX_REQUEST_COUNT at blk_plug for multiple_queues
block: move fs/block_dev.c to block/bdev.c
block: split out operations on block special files
blk-throttle: fix UAF by deleteing timer in blk_throtl_exit()
block: genhd: don't call blkdev_show() with major_names_lock held
nvme: update MAINTAINERS email address
nvme: add error handling support for add_disk()
nvme: only call synchronize_srcu when clearing current path
nvme: update keep alive interval when kato is modified
nvme-tcp: Do not reset transport on data digest errors
nvmet: fixup buffer overrun in nvmet_subsys_attr_serial()
nvmet: return bool from nvmet_passthru_ctrl and nvmet_is_passthru_req
nvmet: looks at the passthrough controller when initializing CAP
nvme: move nvme_multi_css into nvme.h
nvme-multipath: revalidate paths during rescan
nvme-multipath: set QUEUE_FLAG_NOWAIT
Limiting number of request to BLK_MAX_REQUEST_COUNT at blk_plug hurts
performance for large md arrays. [1] shows resync speed of md array drops
for md array with more than 16 HDDs.
Fix this by allowing more request at plug queue. The multiple_queue flag
is used to only apply higher limit to multiple queue cases.
[1] https://lore.kernel.org/linux-raid/CAFDAVznS71BXW8Jxv6k9dXc2iR3ysX3iZRBww_rzA8WifBFxGg@mail.gmail.com/
Tested-by: Marcin Wanat <marcin.wanat@gmail.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new block/fops.c for all the file and address_space operations
that provide the block special file support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210907141303.1371844-2-hch@lst.de
[axboe: correct trailing whitespace while at it]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The pending timer has been set up in blk_throtl_init(). However, the
timer is not deleted in blk_throtl_exit(). This means that the timer
handler may still be running after freeing the timer, which would
result in a use-after-free.
Fix by calling del_timer_sync() to delete the timer in blk_throtl_exit().
Signed-off-by: Li Jinlin <lijinlin3@huawei.com>
Link: https://lore.kernel.org/r/20210907121242.2885564-1-lijinlin3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----
iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmE1hQcQHGF4Ym9lQGtl
cm5lbC5kawAKCRD301j7KXHgprjfEACdG+medwQOPpKNSoAvQmYyQnZRMbPjiruv
A4nW2L6MKaExO59qQLVbBYHaH2+ng2UR/p5jNi2AKm+hrQEYllxlNvuCkRBIn97J
r45R48mzBbHjR4kE3Fdu1mOFpBWOuU9JrtzHI+JF/Sl/qPIxKYNHf5E66T6l90Fz
0hJkorAoVB7+hQYixdmkM9quZy11D5SY3aM+bG8r2uNjZTBEHMfmOen8o1giR0vC
EOHzObuC6WLjLGQInNW+Cq2//vVVybQa79mhOUMp93z5nhDMtwUu7MH4B4kmGpix
GLjDa1DukUZe7nGcnsRKmjjXQ+BpG6YF52Z2RfVZpWZn83t5c4YQsq++TPZ8KfpK
4NAFFuSbGM/+QWwEiiyWu00syvpzrEJ4ZIJyZX3FYEeKyKWVRGHqlMDcS9LstYOk
4OfgQUcJ7f/fXeedwi0OGJS1BLr6fi8RnazIafCNIIJLe1XIwTsNufPCNxWYqDAi
0XhH+uYGD38VoUiR5JymZku6frwY4kxssA1khPPE5jWbzCZXiHprwwzaP4hBNNeZ
c5cn9/1ZQSoTE3ebrX9pzTn5wRZwAL+iDhZ2SpLlN2Ji1BJ4EM9H8qFGj3U/CSM4
OWKY2c0VwJYQUhjO4QDBx0MblJgNy8HsvmqGETuxUlk56j3Q1Mx3ViPV43amP9eM
OM4mGige3Q==
=4SCA
-----END PGP SIGNATURE-----
Merge tag 'block-5.15-2021-09-05' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Was going to send this one in later this week, but given that -Werror
is now enabled (or at least available), the mq-deadline fix really
should go in for the folks hitting that.
- Ensure dd_queued() is only there if needed (Geert)
- Fix a kerneldoc warning for bio_alloc_kiocb()
- BFQ fix for queue merging
- loop locking fix (Tetsuo)"
* tag 'block-5.15-2021-09-05' of git://git.kernel.dk/linux-block:
loop: reduce the loop_ctl_mutex scope
bio: fix kerneldoc documentation for bio_alloc_kiocb()
block, bfq: honor already-setup queue merges
block/mq-deadline: Move dd_queued() to fix defined but not used warning
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
flush_kernel_dcache_page is a rather confusing interface that implements a
subset of flush_dcache_page by not being able to properly handle page
cache mapped pages.
The only callers left are in the exec code as all other previous callers
were incorrect as they could have dealt with page cache pages. Replace
the calls to flush_kernel_dcache_page with calls to flush_dcache_page,
which for all architectures does either exactly the same thing, can
contains one or more of the following:
1) an optimization to defer the cache flush for page cache pages not
mapped into userspace
2) additional flushing for mapped page cache pages if cache aliases
are possible
Link: https://lkml.kernel.org/r/20210712060928.4161649-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Apparently the last fixup got butter fingered a bit, the correct variable
name is 'nr_vecs', not 'nr_iovecs'.
Link: https://lore.kernel.org/lkml/20210903164939.02f6e8c5@canb.auug.org.au/
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This series consists of the usual driver updates (ufs, qla2xxx,
target, smartpqi, lpfc, mpt3sas). The core change causing the most
churn was replacing the command request field request with a macro,
allowing us to offset map to it and remove the redundant field; the
same was also done for the tag field. The most impactful change is
the final removal of scsi_ioctl, which has been deprecated for over a
decade.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
-----BEGIN PGP SIGNATURE-----
iJwEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCYTD/TiYcamFtZXMuYm90
dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pishdUkAQCjb3Ux
4K9438mMelHlzM4er1S1IJ0WNnvObaVMNO9LBwD+JUz+rHsrKvuEX9j3g3C3u6JH
hC3BUEW8f2LLnujWanQ=
=lC5o
-----END PGP SIGNATURE-----
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This series consists of the usual driver updates (ufs, qla2xxx,
target, smartpqi, lpfc, mpt3sas).
The core change causing the most churn was replacing the command
request field request with a macro, allowing us to offset map to it
and remove the redundant field; the same was also done for the tag
field.
The most impactful change is the final removal of scsi_ioctl, which
has been deprecated for over a decade"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (293 commits)
scsi: ufs: Fix ufshcd_request_sense_async() for Samsung KLUFG8RHDA-B2D1
scsi: ufs: ufs-exynos: Fix static checker warning
scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI
scsi: lpfc: Use the proper SCSI midlayer interfaces for PI
scsi: lpfc: Copyright updates for 14.0.0.1 patches
scsi: lpfc: Update lpfc version to 14.0.0.1
scsi: lpfc: Add bsg support for retrieving adapter cmf data
scsi: lpfc: Add cmf_info sysfs entry
scsi: lpfc: Add debugfs support for cm framework buffers
scsi: lpfc: Add support for maintaining the cm statistics buffer
scsi: lpfc: Add rx monitoring statistics
scsi: lpfc: Add support for the CM framework
scsi: lpfc: Add cmfsync WQE support
scsi: lpfc: Add support for cm enablement buffer
scsi: lpfc: Add cm statistics buffer support
scsi: lpfc: Add EDC ELS support
scsi: lpfc: Expand FPIN and RDF receive logging
scsi: lpfc: Add MIB feature enablement support
scsi: lpfc: Add SET_HOST_DATA mbox cmd to pass date/time info to firmware
scsi: fc: Add EDC ELS definition
...
The function bfq_setup_merge prepares the merging between two
bfq_queues, say bfqq and new_bfqq. To this goal, it assigns
bfqq->new_bfqq = new_bfqq. Then, each time some I/O for bfqq arrives,
the process that generated that I/O is disassociated from bfqq and
associated with new_bfqq (merging is actually a redirection). In this
respect, bfq_setup_merge increases new_bfqq->ref in advance, adding
the number of processes that are expected to be associated with
new_bfqq.
Unfortunately, the stable-merging mechanism interferes with this
setup. After bfqq->new_bfqq has been set by bfq_setup_merge, and
before all the expected processes have been associated with
bfqq->new_bfqq, bfqq may happen to be stably merged with a different
queue than the current bfqq->new_bfqq. In this case, bfqq->new_bfqq
gets changed. So, some of the processes that have been already
accounted for in the ref counter of the previous new_bfqq will not be
associated with that queue. This creates an unbalance, because those
references will never be decremented.
This commit fixes this issue by reestablishing the previous, natural
behaviour: once bfqq->new_bfqq has been set, it will not be changed
until all expected redirections have occurred.
Signed-off-by: Davide Zini <davidezini2@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20210802141352.74353-2-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Shin'ichiro Kawasaki
Luis Chamberlain
Yu Kuai
Andrea Righi
Jens Axboe
Linus Torvalds
Naohiro Aota
Ming Lei
Zqiang
Tejun Heo
Paolo Valente
Christoph Hellwig
Johannes Thumshirn
Tetsuo Handa
Li Jinlin
Yanfei Xu
Lihong Kou
Zenghui Yu
Song Liu