linux-stable.git/drivers/md, branch v5.6.4

Revert "dm: always call blk_queue_split() in dm_process_bio()"

2020-04-08T07:11:08+00:00

commit 120c9257f5f19e5d1e87efcbb5531b7cd81b7d74 upstream.

This reverts commit effd58c95f277744f75d6e08819ac859dbcbd351.

blk_queue_split() is causing excessive IO splitting -- because
blk_max_size_offset() depends on 'chunk_sectors' limit being set and
if it isn't (as is the case for DM targets!) it falls back to
splitting on a 'max_sectors' boundary regardless of offset.

"Fix" this by reverting back to _not_ using blk_queue_split() in
dm_process_bio() for normal IO (reads and writes).  Long-term fix is
still TBD but it should focus on training blk_max_size_offset() to
call into a DM provided hook (to call DM's max_io_len()).

Test results from simple misaligned IO test on 4-way dm-striped device
with chunksize of 128K and stripesize of 512K:

xfs_io -d -c 'pread -b 2m 224s 4072s' /dev/mapper/stripe_dev

before this revert:

253,0   21        1     0.000000000  2206  Q   R 224 + 4072 [xfs_io]
253,0   21        2     0.000008267  2206  X   R 224 / 480 [xfs_io]
253,0   21        3     0.000010530  2206  X   R 224 / 256 [xfs_io]
253,0   21        4     0.000027022  2206  X   R 480 / 736 [xfs_io]
253,0   21        5     0.000028751  2206  X   R 480 / 512 [xfs_io]
253,0   21        6     0.000033323  2206  X   R 736 / 992 [xfs_io]
253,0   21        7     0.000035130  2206  X   R 736 / 768 [xfs_io]
253,0   21        8     0.000039146  2206  X   R 992 / 1248 [xfs_io]
253,0   21        9     0.000040734  2206  X   R 992 / 1024 [xfs_io]
253,0   21       10     0.000044694  2206  X   R 1248 / 1504 [xfs_io]
253,0   21       11     0.000046422  2206  X   R 1248 / 1280 [xfs_io]
253,0   21       12     0.000050376  2206  X   R 1504 / 1760 [xfs_io]
253,0   21       13     0.000051974  2206  X   R 1504 / 1536 [xfs_io]
253,0   21       14     0.000055881  2206  X   R 1760 / 2016 [xfs_io]
253,0   21       15     0.000057462  2206  X   R 1760 / 1792 [xfs_io]
253,0   21       16     0.000060999  2206  X   R 2016 / 2272 [xfs_io]
253,0   21       17     0.000062489  2206  X   R 2016 / 2048 [xfs_io]
253,0   21       18     0.000066133  2206  X   R 2272 / 2528 [xfs_io]
253,0   21       19     0.000067507  2206  X   R 2272 / 2304 [xfs_io]
253,0   21       20     0.000071136  2206  X   R 2528 / 2784 [xfs_io]
253,0   21       21     0.000072764  2206  X   R 2528 / 2560 [xfs_io]
253,0   21       22     0.000076185  2206  X   R 2784 / 3040 [xfs_io]
253,0   21       23     0.000077486  2206  X   R 2784 / 2816 [xfs_io]
253,0   21       24     0.000080885  2206  X   R 3040 / 3296 [xfs_io]
253,0   21       25     0.000082316  2206  X   R 3040 / 3072 [xfs_io]
253,0   21       26     0.000085788  2206  X   R 3296 / 3552 [xfs_io]
253,0   21       27     0.000087096  2206  X   R 3296 / 3328 [xfs_io]
253,0   21       28     0.000093469  2206  X   R 3552 / 3808 [xfs_io]
253,0   21       29     0.000095186  2206  X   R 3552 / 3584 [xfs_io]
253,0   21       30     0.000099228  2206  X   R 3808 / 4064 [xfs_io]
253,0   21       31     0.000101062  2206  X   R 3808 / 3840 [xfs_io]
253,0   21       32     0.000104956  2206  X   R 4064 / 4096 [xfs_io]
253,0   21       33     0.001138823     0  C   R 4096 + 200 [0]

after this revert:

253,0   18        1     0.000000000  4430  Q   R 224 + 3896 [xfs_io]
253,0   18        2     0.000018359  4430  X   R 224 / 256 [xfs_io]
253,0   18        3     0.000028898  4430  X   R 256 / 512 [xfs_io]
253,0   18        4     0.000033535  4430  X   R 512 / 768 [xfs_io]
253,0   18        5     0.000065684  4430  X   R 768 / 1024 [xfs_io]
253,0   18        6     0.000091695  4430  X   R 1024 / 1280 [xfs_io]
253,0   18        7     0.000098494  4430  X   R 1280 / 1536 [xfs_io]
253,0   18        8     0.000114069  4430  X   R 1536 / 1792 [xfs_io]
253,0   18        9     0.000129483  4430  X   R 1792 / 2048 [xfs_io]
253,0   18       10     0.000136759  4430  X   R 2048 / 2304 [xfs_io]
253,0   18       11     0.000152412  4430  X   R 2304 / 2560 [xfs_io]
253,0   18       12     0.000160758  4430  X   R 2560 / 2816 [xfs_io]
253,0   18       13     0.000183385  4430  X   R 2816 / 3072 [xfs_io]
253,0   18       14     0.000190797  4430  X   R 3072 / 3328 [xfs_io]
253,0   18       15     0.000197667  4430  X   R 3328 / 3584 [xfs_io]
253,0   18       16     0.000218751  4430  X   R 3584 / 3840 [xfs_io]
253,0   18       17     0.000226005  4430  X   R 3840 / 4096 [xfs_io]
253,0   18       18     0.000250404  4430  Q   R 4120 + 176 [xfs_io]
253,0   18       19     0.000847708     0  C   R 4096 + 24 [0]
253,0   18       20     0.000855783     0  C   R 4120 + 176 [0]

Fixes: effd58c95f27774 ("dm: always call blk_queue_split() in dm_process_bio()")
Cc: stable@vger.kernel.org
Reported-by: Andreas Gruenbacher 
Tested-by: Barry Marson 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block

2020-03-07T20:14:38+00:00

Pull block fixes from Jens Axboe:
 "Here are a few fixes that should go into this release. This contains:

   - Revert of a bad bcache patch from this merge window

   - Removed unused function (Daniel)

   - Fixup for the blktrace fix from Jan from this release (Cengiz)

   - Fix of deeper level bfqq overwrite in BFQ (Carlo)"

* tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
  block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
  blktrace: fix dereference after null check
  Revert "bcache: ignore pending signals when creating gc and allocator thread"
  block: Remove used kblockd_schedule_work_on()

Merge tag 'for-5.6/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2020-03-04T19:02:45+00:00

Pull device mapper fixes from Mike Snitzer:

- Fix request-based DM's congestion_fn and actually wire it up to the
bdi.

- Extend dm-bio-record to track additional struct bio members needed by
DM integrity target.

- Fix DM core to properly advertise that a device is suspended during
unload (between the presuspend and postsuspend hooks). This change is
a prereq for related DM integrity and DM writecache fixes. It
elevates DM integrity's 'suspending' state tracking to DM core.

- Four stable fixes for DM integrity target.

- Fix crash in DM cache target due to incorrect work item cancelling.

- Fix DM thin metadata lockdep warning that was introduced during 5.6
merge window.

- Fix DM zoned target's chunk work refcounting that regressed during
recent conversion to refcount_t.

- Bump the minor version for DM core and all target versions that have
seen interface changes or important fixes during the 5.6 cycle.

* tag 'for-5.6/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: bump version of core and various targets
dm: fix congested_fn for request-based device
dm integrity: use dm_bio_record and dm_bio_restore
dm bio record: save/restore bi_end_io and bi_integrity
dm zoned: Fix reference counter initial value of chunk works
dm writecache: verify watermark during resume
dm: report suspended device during destroy
dm thin metadata: fix lockdep complaint
dm cache: fix a crash due to incorrect work item cancelling
dm integrity: fix invalid table returned due to argument count mismatch
dm integrity: fix a deadlock due to offloading to an incorrect workqueue
dm integrity: fix recalculation when moving from journal mode to bitmap mode

dm: bump version of core and various targets

2020-03-03T16:10:21+00:00

Changes made during the 5.6 cycle warrant bumping the version number
for DM core and the targets modified by this commit.

It should be noted that dm-thin, dm-crypt and dm-raid already had
their target version bumped during the 5.6 merge window.

Signed-off-by; Mike Snitzer

dm: fix congested_fn for request-based device

2020-03-03T16:10:20+00:00

We neither assign congested_fn for requested-based blk-mq device nor
implement it correctly. So fix both.

Also, remove incorrect comment from dm_init_normal_md_queue and rename
it to dm_init_congested_fn.

Fixes: 4aa9c692e052 ("bdi: separate out congested state into a separate struct")
Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao 
Signed-off-by: Mike Snitzer

dm integrity: use dm_bio_record and dm_bio_restore

2020-03-03T15:02:47+00:00

In cases where dec_in_flight() has to requeue the integrity_bio_wait
work to transfer the rest of the data, the bio's __bi_remaining might
already have been decremented to 0, e.g.: if bio passed to underlying
data device was split via blk_queue_split().

Use dm_bio_{record,restore} rather than effectively open-coding them in
dm-integrity -- these methods now manage __bi_remaining too.

Depends-on: f7f0b057a9c1 ("dm bio record: save/restore bi_end_io and bi_integrity")
Reported-by: Daniel Glöckner 
Suggested-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm bio record: save/restore bi_end_io and bi_integrity

2020-03-03T15:02:46+00:00

Also, save/restore __bi_remaining in case the bio was used in a
BIO_CHAIN (e.g. due to blk_queue_split).

Suggested-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

Revert "bcache: ignore pending signals when creating gc and allocator thread"

2020-03-03T03:01:32+00:00

This reverts commit 0b96da639a4874311e9b5156405f69ef9fc3bef8.

We can't just go flushing random signals, under the assumption that the
OOM killer will just do something else. It's not safe from the OOM
perspective, and it could also cause other signals to get randomly lost.

Signed-off-by: Jens Axboe

dm zoned: Fix reference counter initial value of chunk works

2020-02-27T21:44:25+00:00

Dm-zoned initializes reference counters of new chunk works with zero
value and refcount_inc() is called to increment the counter. However, the
refcount_inc() function handles the addition to zero value as an error
and triggers the warning as follows:

refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 1506 at lib/refcount.c:25 refcount_warn_saturate+0x68/0xf0
...
CPU: 7 PID: 1506 Comm: systemd-udevd Not tainted 5.4.0+ #134
...
Call Trace:
 dmz_map+0x2d2/0x350 [dm_zoned]
 __map_bio+0x42/0x1a0
 __split_and_process_non_flush+0x14a/0x1b0
 __split_and_process_bio+0x83/0x240
 ? kmem_cache_alloc+0x165/0x220
 dm_process_bio+0x90/0x230
 ? generic_make_request_checks+0x2e7/0x680
 dm_make_request+0x3e/0xb0
 generic_make_request+0xcf/0x320
 ? memcg_drain_all_list_lrus+0x1c0/0x1c0
 submit_bio+0x3c/0x160
 ? guard_bio_eod+0x2c/0x130
 mpage_readpages+0x182/0x1d0
 ? bdev_evict_inode+0xf0/0xf0
 read_pages+0x6b/0x1b0
 __do_page_cache_readahead+0x1ba/0x1d0
 force_page_cache_readahead+0x93/0x100
 generic_file_read_iter+0x83a/0xe40
 ? __seccomp_filter+0x7b/0x670
 new_sync_read+0x12a/0x1c0
 vfs_read+0x9d/0x150
 ksys_read+0x5f/0xe0
 do_syscall_64+0x5b/0x180
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
...

After this warning, following refcount API calls for the counter all fail
to change the counter value.

Fix this by setting the initial reference counter value not zero but one
for the new chunk works. Instead, do not call refcount_inc() via
dmz_get_chunk_work() for the new chunks works.

The failure was observed with linux version 5.4 with CONFIG_REFCOUNT_FULL
enabled. Refcount rework was merged to linux version 5.5 by the
commit 168829ad09ca ("Merge branch 'locking-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip"). After this
commit, CONFIG_REFCOUNT_FULL was removed and the failure was observed
regardless of kernel configuration.

Linux version 4.20 merged the commit 092b5648760a ("dm zoned: target: use
refcount_t for dm zoned reference counters"). Before this commit, dm
zoned used atomic_t APIs which does not check addition to zero, then this
fix is not necessary.

Fixes: 092b5648760a ("dm zoned: target: use refcount_t for dm zoned reference counters")
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Shin'ichiro Kawasaki 
Reviewed-by: Damien Le Moal 
Signed-off-by: Mike Snitzer

dm writecache: verify watermark during resume

2020-02-27T21:44:24+00:00

Verify the watermark upon resume - so that if the target is reloaded
with lower watermark, it will start the cleanup process immediately.

Fixes: 48debafe4f2f ("dm: add writecache target")
Cc: stable@vger.kernel.org # 4.18+
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer