linux_dsm_epyc7002/drivers/md
NeilBrown 8dd601fa83 dm: correctly handle chained bios in dec_pending()
dec_pending() is given an error status (possibly 0) to be recorded
against a bio.  It can be called several times on the one 'struct
dm_io', and it is careful to only assign a non-zero error to
io->status.  However when it then assigned io->status to bio->bi_status,
it is not careful and could overwrite a genuine error status with 0.

This can happen when chained bios are in use.  If a bio is chained
beneath the bio that this dm_io is handling, the child bio might
complete and set bio->bi_status before the dm_io completes.

This has been possible since chained bios were introduced in 3.14, and
has become a lot easier to trigger with commit 18a25da843 ("dm: ensure
bio submission follows a depth-first tree walk") as that commit caused
dm to start using chained bios itself.

A particular failure mode is that if a bio spans an 'error' target and a
working target, the 'error' fragment will complete instantly and set the
->bi_status, and the other fragment will normally complete a little
later, and will clear ->bi_status.

The fix is simply to only assign io_error to bio->bi_status when
io_error is not zero.

Reported-and-tested-by: Milan Broz <gmazyland@gmail.com>
Cc: stable@vger.kernel.org (v3.14+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-02-16 10:46:35 -05:00
..
bcache bcache: fix for data collapse after re-attaching an attached device 2018-02-07 12:50:01 -07:00
persistent-data dm btree: fix serious bug in btree_split_beneath() 2018-01-17 09:07:55 -05:00
dm-bio-prison-v1.c dm bio prison: use rb_entry() rather than container_of() 2017-06-19 11:03:50 -04:00
dm-bio-prison-v1.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
dm-bio-prison-v2.c dm bio prison: use rb_entry() rather than container_of() 2017-06-19 11:03:50 -04:00
dm-bio-prison-v2.h
dm-bio-record.h block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
dm-bufio.c dm bufio: eliminate unnecessary labels in dm_bufio_client_create() 2018-01-17 09:16:04 -05:00
dm-bufio.h dm integrity: optimize writing dm-bufio buffers that are partially changed 2017-08-28 11:47:17 -04:00
dm-builtin.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dm-cache-background-tracker.c dm cache background tracker: limit amount of background work that may be issued at once 2017-11-10 15:45:03 -05:00
dm-cache-background-tracker.h
dm-cache-block-types.h
dm-cache-metadata.c dm cache: convert dm_cache_metadata.ref_count from atomic_t to refcount_t 2017-10-24 15:09:51 -04:00
dm-cache-metadata.h
dm-cache-policy-internal.h
dm-cache-policy-smq.c dm cache policy smq: allocate cache blocks in order 2017-11-10 15:45:05 -05:00
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c dm: fix various targets to dm_register_target after module __init resources created 2017-12-04 10:23:10 -05:00
dm-core.h dm: various cleanups to md->queue initialization code 2018-01-29 13:44:55 -05:00
dm-crypt.c - DM core fixes to ensure that bio submission follows a depth-first tree 2018-01-31 11:05:47 -08:00
dm-delay.c dm: backfill missing calls to mutex_destroy() 2018-01-17 09:16:15 -05:00
dm-era-target.c dm: do not set 'discards_supported' in targets that do not need it 2017-11-16 16:33:54 -05:00
dm-exception-store.c
dm-exception-store.h
dm-flakey.c dm flakey: check for null arg_name in parse_features() 2018-01-17 09:16:13 -05:00
dm-integrity.c dm integrity: don't store cipher request on the stack 2018-01-17 09:08:57 -05:00
dm-io.c dm io: remove BIOSET_NEED_RESCUER flag from bios bioset 2017-12-13 12:15:56 -05:00
dm-ioctl.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
dm-kcopyd.c dm: backfill missing calls to mutex_destroy() 2018-01-17 09:16:15 -05:00
dm-linear.c - Some request-based DM core and DM multipath fixes and cleanups 2017-09-14 13:43:16 -07:00
dm-log-userspace-base.c
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c dm log writes: fix max length used for kstrndup 2018-01-17 09:16:16 -05:00
dm-log.c
dm-mpath.c - DM core fixes to ensure that bio submission follows a depth-first tree 2018-01-31 11:05:47 -08:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c dm mpath selector: more evenly distribute ties 2018-01-29 13:44:58 -05:00
dm-raid1.c md: Convert timers to use timer_setup() 2017-11-14 20:11:57 -07:00
dm-raid.c - DM core fixes to ensure that bio submission follows a depth-first tree 2018-01-31 11:05:47 -08:00
dm-region-hash.c
dm-round-robin.c
dm-rq.c for-linus-20180204 2018-02-04 11:16:35 -08:00
dm-rq.h dm rq: do not update rq partially in each ending bio 2017-08-28 10:23:28 -04:00
dm-service-time.c dm mpath selector: more evenly distribute ties 2018-01-29 13:44:58 -05:00
dm-snap-persistent.c dm: make flush bios explicitly sync 2017-05-31 10:50:23 -04:00
dm-snap-transient.c
dm-snap.c dm snapshot: use mutex instead of rw_semaphore 2018-01-17 09:16:14 -05:00
dm-stats.c dm: backfill missing calls to mutex_destroy() 2018-01-17 09:16:15 -05:00
dm-stats.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dm-stripe.c - Some request-based DM core and DM multipath fixes and cleanups 2017-09-14 13:43:16 -07:00
dm-switch.c locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() 2017-10-25 11:01:08 +02:00
dm-sysfs.c
dm-table.c dm table: fix NVMe bio-based dm_table_determine_type() validation 2018-01-29 13:44:56 -05:00
dm-target.c dm: don't return errnos from ->map 2017-06-09 09:27:32 -06:00
dm-thin-metadata.c dm thin metadata: THIN_MAX_CONCURRENT_LOCKS should be 6 2018-01-17 09:07:54 -05:00
dm-thin-metadata.h
dm-thin.c dm thin: fix trailing semicolon in __remap_and_issue_shared_cell 2018-01-29 13:44:57 -05:00
dm-uevent.c
dm-uevent.h
dm-unstripe.c dm unstripe: fix target length versus number of stripes size check 2018-01-29 13:44:58 -05:00
dm-verity-fec.c dm verity fec: fix GFP flags used with mempool_alloc() 2017-07-26 15:55:44 -04:00
dm-verity-fec.h
dm-verity-target.c Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-14 10:52:09 -08:00
dm-verity.h dm: move dm-verity to generic async completion 2017-11-03 22:11:20 +08:00
dm-zero.c dm: don't return errnos from ->map 2017-06-09 09:27:32 -06:00
dm-zoned-metadata.c dm: backfill missing calls to mutex_destroy() 2018-01-17 09:16:15 -05:00
dm-zoned-reclaim.c dm zoned: use GFP_NOIO in I/O path 2017-07-26 15:55:43 -04:00
dm-zoned-target.c dm: backfill missing calls to mutex_destroy() 2018-01-17 09:16:15 -05:00
dm-zoned.h dm zoned: drive-managed zoned block device target 2017-06-19 11:05:20 -04:00
dm.c dm: correctly handle chained bios in dec_pending() 2018-02-16 10:46:35 -05:00
dm.h dm: move dm_table_destroy() to same header as dm_table_create() 2018-01-17 09:16:06 -05:00
Kconfig dm: add unstriped target 2018-01-17 09:16:00 -05:00
Makefile dm: add unstriped target 2018-01-17 09:16:00 -05:00
md-bitmap.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00
md-bitmap.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00
md-cluster.c md-cluster: update document for raid10 2017-11-01 21:32:25 -07:00
md-cluster.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
md-faulty.c md: rename some drivers/md/ files to have an "md-" prefix 2017-10-16 19:06:36 -07:00
md-linear.c md: rename some drivers/md/ files to have an "md-" prefix 2017-10-16 19:06:36 -07:00
md-linear.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00
md-multipath.c md: remove redundant variable q 2017-11-01 21:32:24 -07:00
md-multipath.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00
md.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
md.h raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
raid0.c md: remove special meaning of ->quiesce(.., 2) 2017-11-01 21:32:20 -07:00
raid0.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
raid1-10.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
raid1.c md/raid1,raid10: silence warning about wait-within-wait 2017-12-11 08:52:34 -08:00
raid1.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
raid5-cache.c raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
raid5-log.h raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
raid5-ppl.c raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
raid5.c raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
raid5.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
raid10.c md/raid1,raid10: silence warning about wait-within-wait 2017-12-11 08:52:34 -08:00
raid10.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00