linux-uconsole/drivers/md
Dennis Yang c5ff397f07 md: update slab_cache before releasing new stripes when stripes resizing
commit 583da48e38 upstream.

When growing raid5 device on machine with small memory, there is chance that
mdadm will be killed and the following bug report can be observed. The same
bug could also be reproduced in linux-4.10.6.

[57600.075774] BUG: unable to handle kernel NULL pointer dereference at           (null)
[57600.083796] IP: [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20
[57600.110378] PGD 421cf067 PUD 4442d067 PMD 0
[57600.114678] Oops: 0002 [#1] SMP
[57600.180799] CPU: 1 PID: 25990 Comm: mdadm Tainted: P           O    4.2.8 #1
[57600.187849] Hardware name: To be filled by O.E.M. To be filled by O.E.M./MAHOBAY, BIOS QV05AR66 03/06/2013
[57600.197490] task: ffff880044e47240 ti: ffff880043070000 task.ti: ffff880043070000
[57600.204963] RIP: 0010:[<ffffffff81a6aa87>]  [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20
[57600.213057] RSP: 0018:ffff880043073810  EFLAGS: 00010046
[57600.218359] RAX: 0000000000000000 RBX: 000000000000000c RCX: ffff88011e296dd0
[57600.225486] RDX: 0000000000000001 RSI: ffffe8ffffcb46c0 RDI: 0000000000000000
[57600.232613] RBP: ffff880043073878 R08: ffff88011e5f8170 R09: 0000000000000282
[57600.239739] R10: 0000000000000005 R11: 28f5c28f5c28f5c3 R12: ffff880043073838
[57600.246872] R13: ffffe8ffffcb46c0 R14: 0000000000000000 R15: ffff8800b9706a00
[57600.253999] FS:  00007f576106c700(0000) GS:ffff88011e280000(0000) knlGS:0000000000000000
[57600.262078] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[57600.267817] CR2: 0000000000000000 CR3: 00000000428fe000 CR4: 00000000001406e0
[57600.274942] Stack:
[57600.276949]  ffffffff8114ee35 ffff880043073868 0000000000000282 000000000000eb3f
[57600.284383]  ffffffff81119043 ffff880043073838 ffff880043073838 ffff88003e197b98
[57600.291820]  ffffe8ffffcb46c0 ffff88003e197360 0000000000000286 ffff880043073968
[57600.299254] Call Trace:
[57600.301698]  [<ffffffff8114ee35>] ? cache_flusharray+0x35/0xe0
[57600.307523]  [<ffffffff81119043>] ? __page_cache_release+0x23/0x110
[57600.313779]  [<ffffffff8114eb53>] kmem_cache_free+0x63/0xc0
[57600.319344]  [<ffffffff81579942>] drop_one_stripe+0x62/0x90
[57600.324915]  [<ffffffff81579b5b>] raid5_cache_scan+0x8b/0xb0
[57600.330563]  [<ffffffff8111b98a>] shrink_slab.part.36+0x19a/0x250
[57600.336650]  [<ffffffff8111e38c>] shrink_zone+0x23c/0x250
[57600.342039]  [<ffffffff8111e4f3>] do_try_to_free_pages+0x153/0x420
[57600.348210]  [<ffffffff8111e851>] try_to_free_pages+0x91/0xa0
[57600.353959]  [<ffffffff811145b1>] __alloc_pages_nodemask+0x4d1/0x8b0
[57600.360303]  [<ffffffff8157a30b>] check_reshape+0x62b/0x770
[57600.365866]  [<ffffffff8157a4a5>] raid5_check_reshape+0x55/0xa0
[57600.371778]  [<ffffffff81583df7>] update_raid_disks+0xc7/0x110
[57600.377604]  [<ffffffff81592b73>] md_ioctl+0xd83/0x1b10
[57600.382827]  [<ffffffff81385380>] blkdev_ioctl+0x170/0x690
[57600.388307]  [<ffffffff81195238>] block_ioctl+0x38/0x40
[57600.393525]  [<ffffffff811731c5>] do_vfs_ioctl+0x2b5/0x480
[57600.399010]  [<ffffffff8115e07b>] ? vfs_write+0x14b/0x1f0
[57600.404400]  [<ffffffff811733cc>] SyS_ioctl+0x3c/0x70
[57600.409447]  [<ffffffff81a6ad97>] entry_SYSCALL_64_fastpath+0x12/0x6a
[57600.415875] Code: 00 00 00 00 55 48 89 e5 8b 07 85 c0 74 04 31 c0 5d c3 ba 01 00 00 00 f0 0f b1 17 85 c0 75 ef b0 01 5d c3 90 31 c0 ba 01 00 00 00 <f0> 0f b1 17 85 c0 75 01 c3 55 89 c6 48 89 e5 e8 85 d1 63 ff 5d
[57600.435460] RIP  [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20
[57600.441208]  RSP <ffff880043073810>
[57600.444690] CR2: 0000000000000000
[57600.448000] ---[ end trace cbc6b5cc4bf9831d ]---

The problem is that resize_stripes() releases new stripe_heads before assigning new
slab cache to conf->slab_cache. If the shrinker function raid5_cache_scan() gets called
after resize_stripes() starting releasing new stripes but right before new slab cache
being assigned, it is possible that these new stripe_heads will be freed with the old
slab_cache which was already been destoryed and that triggers this bug.

Signed-off-by: Dennis Yang <dennisyang@qnap.com>
Fixes: edbe83ab4c ("md/raid5: allow the stripe_cache to grow and shrink.")
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:08 +02:00
..
bcache bcache: Make gc wakeup sane, remove set_task_state() 2017-02-23 17:43:10 +01:00
persistent-data dm space map disk: fix some book keeping in the disk space map 2017-05-25 14:30:08 +02:00
bitmap.c md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
bitmap.h md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
dm-bio-prison.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
dm-bio-prison.h dm bio prison: add dm_cell_promote_or_release() 2015-05-29 14:19:06 -04:00
dm-bio-record.h
dm-bufio.c dm bufio: make the parameter "retain_bytes" unsigned long 2017-05-25 14:30:08 +02:00
dm-bufio.h
dm-builtin.c
dm-cache-block-types.h
dm-cache-metadata.c dm cache metadata: fail operations if fail_io mode has been established 2017-05-25 14:30:08 +02:00
dm-cache-metadata.h dm cache: make sure every metadata function checks fail_io 2016-04-12 09:08:40 -07:00
dm-cache-policy-cleaner.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-cache-policy-internal.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-policy-mq.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-cache-policy-smq.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-cache-policy.c
dm-cache-policy.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-target.c dm cache: fix corruption seen when using cache > 2TB 2017-03-12 06:37:26 +01:00
dm-crypt.c dm crypt: mark key as invalid until properly loaded 2017-01-06 11:16:15 +01:00
dm-delay.c dm delay: document that offsets are specified in sectors 2015-10-31 19:06:05 -04:00
dm-era-target.c dm era: save spacemap metadata root after the pre-commit 2017-05-20 14:27:00 +02:00
dm-exception-store.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-exception-store.h dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-flakey.c dm flakey: return -EINVAL on interval bounds error in flakey_ctr() 2017-01-06 11:16:15 +01:00
dm-io.c dm: drop NULL test before kmem_cache_destroy() and mempool_destroy() 2015-10-31 19:06:00 -04:00
dm-ioctl.c dm ioctl: prevent stack leak in dm ioctl call 2017-05-08 07:46:02 +02:00
dm-kcopyd.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
dm-linear.c dm linear: remove redundant target name from error messages 2015-10-31 19:06:03 -04:00
dm-log-userspace-base.c dm: drop NULL test before kmem_cache_destroy() and mempool_destroy() 2015-10-31 19:06:00 -04:00
dm-log-userspace-transfer.c dm log userspace transfer: match wait_for_completion_timeout return type 2015-04-15 12:10:20 -04:00
dm-log-userspace-transfer.h
dm-log-writes.c dm log writes: fix bug with too large bios 2016-10-07 15:23:47 +02:00
dm-log.c
dm-mpath.c dm mpath: check if path's request_queue is dying in activate_path() 2016-10-28 03:01:28 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid.c dm raid: fix round up of default region size 2015-10-02 12:02:31 -04:00
dm-raid1.c dm mirror: fix read error on recovery after default leg failure 2016-11-10 16:36:35 +01:00
dm-region-hash.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-snap-transient.c dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-snap.c dm snapshot: disallow the COW and origin devices from being identical 2016-04-12 09:08:39 -07:00
dm-stats.c dm stats: fix a leaked s->histogram_boundaries array 2017-03-12 06:37:26 +01:00
dm-stats.h dm stats: support precise timestamps 2015-06-17 12:40:40 -04:00
dm-stripe.c Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm 2015-09-02 16:35:26 -07:00
dm-switch.c dm switch: simplify conditional in alloc_region_table() 2015-10-31 19:06:06 -04:00
dm-sysfs.c dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
dm-table.c dm snapshot: disallow the COW and origin devices from being identical 2016-04-12 09:08:39 -07:00
dm-target.c dm: allocate requests in target when stacking on blk-mq devices 2015-02-09 13:06:47 -05:00
dm-thin-metadata.c dm thin metadata: call precommit before saving the roots 2017-05-25 14:30:08 +02:00
dm-thin-metadata.h dm thin metadata: add dm_thin_remove_range() 2015-06-11 17:13:04 -04:00
dm-thin.c dm thin: fix race condition when destroying thin pool workqueue 2016-03-03 15:07:10 -08:00
dm-uevent.c
dm-uevent.h
dm-verity.c dm: refactor ioctl handling 2015-10-31 19:05:59 -04:00
dm-zero.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
dm.c blk: Ensure users for current->bio_list can see the full list. 2017-04-08 09:53:32 +02:00
dm.h block: kill merge_bvec_fn() completely 2015-08-13 12:31:57 -06:00
faulty.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
Kconfig dm raid: select the Kconfig option CONFIG_MD_RAID0 2017-05-25 14:30:07 +02:00
linear.c md linear: fix a race between linear_add() and linear_congested() 2017-03-12 06:37:30 +01:00
linear.h md linear: fix a race between linear_add() and linear_congested() 2017-03-12 06:37:30 +01:00
Makefile raid5: add basic stripe log 2015-10-24 17:16:19 +11:00
md-cluster.c md-cluster: remove mddev arg from add_resync_info() 2015-10-24 17:16:18 +11:00
md-cluster.h md-cluster: Fix adding of new disk with new reload code 2015-10-12 03:35:30 -05:00
md.c md: MD_RECOVERY_NEEDED is set for mddev->recovery 2017-01-12 11:22:50 +01:00
md.h md/raid: only permit hot-add of compatible integrity profiles 2016-02-17 12:30:57 -08:00
multipath.c md: multipath: don't hardcopy bio in .make_request path 2016-04-12 09:08:57 -07:00
multipath.h
raid0.c md/raid0: apply base queue limits *before* disk_stack_limits 2015-10-02 17:23:44 +10:00
raid0.h block: kill merge_bvec_fn() completely 2015-08-13 12:31:57 -06:00
raid1.c md:raid1: fix a dead loop when read from a WriteMostly disk 2017-05-02 21:19:48 -07:00
raid1.h md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
raid5-cache.c raid5-cache: start raid5 readonly if journal is missing 2015-11-01 13:48:29 +11:00
raid5.c md: update slab_cache before releasing new stripes when stripes resizing 2017-05-25 14:30:08 +02:00
raid5.h RAID5: revert e9e4c377e2 to fix a livelock 2016-04-12 09:08:57 -07:00
raid10.c blk: Ensure users for current->bio_list can see the full list. 2017-04-08 09:53:32 +02:00
raid10.h md/raid10: ensure device failure recorded before write request returns. 2015-08-31 19:43:45 +02:00