linux-stable.git/drivers/md, branch linux-2.6.39.y Linux kernel stable tree md: avoid endless recovery loop when waiting for fail device to complete. 2011-07-09T06:15:29+00:00 NeilBrown neilb@suse.de 2011-06-28T06:59:42+00:00 1ba0b35675c0acec330a0b19c1e7ce9d8acb55f6 commit 4274215d24633df7302069e51426659d4759c5ed upstream. If a device fails in a way that causes pending request to take a while to complete, md will not be able to immediately remove it from the array in remove_and_add_spares. It will then incorrectly look like a spare device and md will try to recover it even though it is failed. This leads to a recovery process starting and instantly aborting over and over again. We should check if the device is faulty before considering it to be a spare. This will avoid trying to start a recovery that cannot proceed. This bug was introduced in 2.6.26 so that patch is suitable for any kernel since then. Reported-by: Jim Paradis <james.paradis@stratus.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 4274215d24633df7302069e51426659d4759c5ed upstream.

If a device fails in a way that causes pending request to take a while
to complete, md will not be able to immediately remove it from the
array in remove_and_add_spares.
It will then incorrectly look like a spare device and md will try to
recover it even though it is failed.
This leads to a recovery process starting and instantly aborting over
and over again.

We should check if the device is faulty before considering it to be a
spare.  This will avoid trying to start a recovery that cannot
proceed.

This bug was introduced in 2.6.26 so that patch is suitable for any
kernel since then.

Reported-by: Jim Paradis <james.paradis@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
md/raid5: fix FUA request handling in ops_run_io() 2011-06-23T22:05:41+00:00 Namhyung Kim namhyung@gmail.com 2011-06-14T04:20:19+00:00 2cd3e43e8db9d0ae1af443418547f65ee1efa280 commit b062962edb086011e94ec4d9eb3f6a6d814f2a8f upstream. Commit e9c7469bb4f5 ("md: implment REQ_FLUSH/FUA support") introduced R5_WantFUA flag and set rw to WRITE_FUA in that case. However remaining code still checks whether rw is exactly same as WRITE or not, so FUAed-write ends up with being treated as READ. Fix it. This bug has been present since 2.6.37 and the fix is suitable for any -stable kernel since then. It is not clear why this has not caused more problems. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit b062962edb086011e94ec4d9eb3f6a6d814f2a8f upstream.

Commit e9c7469bb4f5 ("md: implment REQ_FLUSH/FUA support")
introduced R5_WantFUA flag and set rw to WRITE_FUA in that case.
However remaining code still checks whether rw is exactly same
as WRITE or not, so FUAed-write ends up with being treated as
READ. Fix it.

This bug has been present since 2.6.37 and the fix is suitable for any
-stable kernel since then.  It is not clear why this has not caused
more problems.

Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
md/raid5: fix raid5_set_bi_hw_segments 2011-06-23T22:05:41+00:00 Namhyung Kim namhyung@gmail.com 2011-06-13T05:48:22+00:00 fbfa65f9e3eb26937a90f023a8fd4d181189c1ef commit 9b2dc8b665932a8e681a7ab3237f60475e75e161 upstream. The @bio->bi_phys_segments consists of active stripes count in the lower 16 bits and processed stripes count in the upper 16 bits. So logical-OR operator should be bitwise one. This bug has been present since 2.6.27 and the fix is suitable for any -stable kernel since then. Fortunately the bad code is only used on error paths and is relatively unlikely to be hit. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 9b2dc8b665932a8e681a7ab3237f60475e75e161 upstream.

The @bio->bi_phys_segments consists of active stripes count in the
lower 16 bits and processed stripes count in the upper 16 bits. So
logical-OR operator should be bitwise one.

This bug has been present since 2.6.27 and the fix is suitable for any
-stable kernel since then.  Fortunately the bad code is only used on
error paths and is relatively unlikely to be hit.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
md: check ->hot_remove_disk when removing disk 2011-06-23T22:05:40+00:00 Namhyung Kim namhyung@gmail.com 2011-06-09T01:42:54+00:00 1d15c2e0b935bcc27fe802655058051f934adf1d commit 01393f3d5836b7d62e925e6f4658a7eb22b83a11 upstream. Check pers->hot_remove_disk instead of pers->hot_add_disk in slot_store() during disk removal. The linear personality only has ->hot_add_disk and no ->hot_remove_disk, so that removing disk in the array resulted to following kernel bug: $ sudo mdadm --create /dev/md0 --level=linear --raid-devices=4 /dev/loop[0-3] $ echo none | sudo tee /sys/block/md0/md/dev-loop2/slot BUG: unable to handle kernel NULL pointer dereference at (null) IP: [< (null)>] (null) PGD c9f5d067 PUD 8575a067 PMD 0 Oops: 0010 [#1] SMP CPU 2 Modules linked in: linear loop bridge stp llc kvm_intel kvm asus_atk0110 sr_mod cdrom sg Pid: 10450, comm: tee Not tainted 3.0.0-rc1-leonard+ #173 System manufacturer System Product Name/P5G41TD-M PRO RIP: 0010:[<0000000000000000>] [< (null)>] (null) RSP: 0018:ffff880085757df0 EFLAGS: 00010282 RAX: ffffffffa00168e0 RBX: ffff8800d1431800 RCX: 000000000000006e RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff88008543c000 RBP: ffff880085757e48 R08: 0000000000000002 R09: 000000000000000a R10: 0000000000000000 R11: ffff88008543c2e0 R12: 00000000ffffffff R13: ffff8800b4641000 R14: 0000000000000005 R15: 0000000000000000 FS: 00007fe8c9e05700(0000) GS:ffff88011fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 00000000b4502000 CR4: 00000000000406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process tee (pid: 10450, threadinfo ffff880085756000, task ffff8800c9f08000) Stack: ffffffff8138496a ffff8800b4641000 ffff88008543c268 0000000000000000 ffff8800b4641000 ffff88008543c000 ffff8800d1431868 ffffffff81a78a90 ffff8800b4641000 ffff88008543c000 ffff8800d1431800 ffff880085757e98 Call Trace: [<ffffffff8138496a>] ? slot_store+0xaa/0x265 [<ffffffff81384bae>] rdev_attr_store+0x89/0xa8 [<ffffffff8115a96a>] sysfs_write_file+0x108/0x144 [<ffffffff81106b87>] vfs_write+0xb1/0x10d [<ffffffff8106e6c0>] ? trace_hardirqs_on_caller+0x111/0x135 [<ffffffff81106cac>] sys_write+0x4d/0x77 [<ffffffff814fe702>] system_call_fastpath+0x16/0x1b Code: Bad RIP value. RIP [< (null)>] (null) RSP <ffff880085757df0> CR2: 0000000000000000 ---[ end trace ba5fc64319a826fb ]--- Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 01393f3d5836b7d62e925e6f4658a7eb22b83a11 upstream.

Check pers->hot_remove_disk instead of pers->hot_add_disk in slot_store()
during disk removal. The linear personality only has ->hot_add_disk and
no ->hot_remove_disk, so that removing disk in the array resulted to
following kernel bug:

$ sudo mdadm --create /dev/md0 --level=linear --raid-devices=4 /dev/loop[0-3]
$ echo none | sudo tee /sys/block/md0/md/dev-loop2/slot
 BUG: unable to handle kernel NULL pointer dereference at           (null)
 IP: [<          (null)>]           (null)
 PGD c9f5d067 PUD 8575a067 PMD 0
 Oops: 0010 [#1] SMP
 CPU 2
 Modules linked in: linear loop bridge stp llc kvm_intel kvm asus_atk0110 sr_mod cdrom sg

 Pid: 10450, comm: tee Not tainted 3.0.0-rc1-leonard+ #173 System manufacturer System Product Name/P5G41TD-M PRO
 RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
 RSP: 0018:ffff880085757df0  EFLAGS: 00010282
 RAX: ffffffffa00168e0 RBX: ffff8800d1431800 RCX: 000000000000006e
 RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff88008543c000
 RBP: ffff880085757e48 R08: 0000000000000002 R09: 000000000000000a
 R10: 0000000000000000 R11: ffff88008543c2e0 R12: 00000000ffffffff
 R13: ffff8800b4641000 R14: 0000000000000005 R15: 0000000000000000
 FS:  00007fe8c9e05700(0000) GS:ffff88011fa00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 0000000000000000 CR3: 00000000b4502000 CR4: 00000000000406e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process tee (pid: 10450, threadinfo ffff880085756000, task ffff8800c9f08000)
 Stack:
  ffffffff8138496a ffff8800b4641000 ffff88008543c268 0000000000000000
  ffff8800b4641000 ffff88008543c000 ffff8800d1431868 ffffffff81a78a90
  ffff8800b4641000 ffff88008543c000 ffff8800d1431800 ffff880085757e98
 Call Trace:
  [<ffffffff8138496a>] ? slot_store+0xaa/0x265
  [<ffffffff81384bae>] rdev_attr_store+0x89/0xa8
  [<ffffffff8115a96a>] sysfs_write_file+0x108/0x144
  [<ffffffff81106b87>] vfs_write+0xb1/0x10d
  [<ffffffff8106e6c0>] ? trace_hardirqs_on_caller+0x111/0x135
  [<ffffffff81106cac>] sys_write+0x4d/0x77
  [<ffffffff814fe702>] system_call_fastpath+0x16/0x1b
 Code:  Bad RIP value.
 RIP  [<          (null)>]           (null)
  RSP <ffff880085757df0>
 CR2: 0000000000000000
 ---[ end trace ba5fc64319a826fb ]---

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
dm mpath: do not fail paths after integrity errors 2011-06-03T00:32:36+00:00 Martin K. Petersen martin.petersen@oracle.com 2011-05-29T12:02:55+00:00 7d65f8ababe778107b12acc7b1ab998c03cfe48c commit 6f13f6fba76edc7d0e7580c5deee829d59a41b2f upstream. Integrity errors need to be passed to the owner of the integrity metadata for processing. Consequently EILSEQ should be passed up the stack. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 6f13f6fba76edc7d0e7580c5deee829d59a41b2f upstream.

Integrity errors need to be passed to the owner of the integrity
metadata for processing. Consequently EILSEQ should be passed up the
stack.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
dm table: reject devices without request fns 2011-06-03T00:32:35+00:00 Milan Broz mbroz@redhat.com 2011-05-29T12:02:52+00:00 c43a24963bf8d5dc865186d51c63599a8e5b1fd8 commit f4808ca99a203f20b4475601748e44b25a65bdec upstream. This patch adds a check that a block device has a request function defined before it is used. Otherwise, misconfiguration can cause an oops. Because we are allowing devices with zero size e.g. an offline multipath device as in commit 2cd54d9bedb79a97f014e86c0da393416b264eb3 ("dm: allow offline devices") there needs to be an additional check to ensure devices are initialised. Some block devices, like a loop device without a backing file, exist but have no request function. Reproducer is trivial: dm-mirror on unbound loop device (no backing file on loop devices) dmsetup create x --table "0 8 mirror core 2 8 sync 2 /dev/loop0 0 /dev/loop1 0" and mirror resync will immediatelly cause OOps. BUG: unable to handle kernel NULL pointer dereference at (null) ? generic_make_request+0x2bd/0x590 ? kmem_cache_alloc+0xad/0x190 submit_bio+0x53/0xe0 ? bio_add_page+0x3b/0x50 dispatch_io+0x1ca/0x210 [dm_mod] ? read_callback+0x0/0xd0 [dm_mirror] dm_io+0xbb/0x290 [dm_mod] do_mirror+0x1e0/0x748 [dm_mirror] Signed-off-by: Milan Broz <mbroz@redhat.com> Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit f4808ca99a203f20b4475601748e44b25a65bdec upstream.

This patch adds a check that a block device has a request function
defined before it is used.  Otherwise, misconfiguration can cause an oops.

Because we are allowing devices with zero size e.g. an offline multipath
device as in commit 2cd54d9bedb79a97f014e86c0da393416b264eb3
("dm: allow offline devices") there needs to be an additional check
to ensure devices are initialised.  Some block devices, like a loop
device without a backing file, exist but have no request function.

Reproducer is trivial: dm-mirror on unbound loop device
(no backing file on loop devices)

dmsetup create x --table "0 8 mirror core 2 8 sync 2 /dev/loop0 0 /dev/loop1 0"

and mirror resync will immediatelly cause OOps.

BUG: unable to handle kernel NULL pointer dereference at   (null)
 ? generic_make_request+0x2bd/0x590
 ? kmem_cache_alloc+0xad/0x190
 submit_bio+0x53/0xe0
 ? bio_add_page+0x3b/0x50
 dispatch_io+0x1ca/0x210 [dm_mod]
 ? read_callback+0x0/0xd0 [dm_mirror]
 dm_io+0xbb/0x290 [dm_mod]
 do_mirror+0x1e0/0x748 [dm_mirror]

Signed-off-by: Milan Broz <mbroz@redhat.com>
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
md/bitmap: fix saving of events_cleared and other state. 2011-06-03T00:32:12+00:00 NeilBrown neilb@suse.de 2011-05-11T04:26:30+00:00 a6b2de6dae30c9565999760b91d1c22f77613c9d commit 8258c53208d7a9b7207e7d4dae36d2ea384cb278 upstream. If a bitmap is found to be 'stale' the events_cleared value is set to match 'events'. However if the array is degraded this does not get stored on disk. This can subsequently lead to incorrect behaviour. So change bitmap_update_sb to always update events_cleared in the superblock from the known events_cleared. For neatness also set ->state from ->flags. This requires updating ->state whenever we update ->flags, which makes sense anyway. This is suitable for any active -stable release. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 8258c53208d7a9b7207e7d4dae36d2ea384cb278 upstream.

If a bitmap is found to be 'stale' the events_cleared value
is set to match 'events'.
However if the array is degraded this does not get stored on disk.
This can subsequently lead to incorrect behaviour.

So change bitmap_update_sb to always update events_cleared in the
superblock from the known events_cleared.
For neatness also set ->state from ->flags.
This requires updating ->state whenever we update ->flags, which makes
sense anyway.

This is suitable for any active -stable release.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
md: Fix race when creating a new md device. 2011-06-03T00:32:12+00:00 NeilBrown neilb@suse.de 2011-05-10T07:49:01+00:00 37c90a7e80f988b23618db27e3b06ba4c6ea1eab commit b0140891a8cea36469f58d23859e599b1122bd37 upstream. There is a race when creating an md device by opening /dev/mdXX. If two processes do this at much the same time they will follow the call path __blkdev_get -> get_gendisk -> kobj_lookup The first will call -> md_probe -> md_alloc -> add_disk -> blk_register_region and the race happens when the second gets to kobj_lookup after add_disk has called blk_register_region but before it returns to md_alloc. In the case the second will not call md_probe (as the probe is already done) but will get a handle on the gendisk, return to __blkdev_get which will then call md_open (via the ->open) pointer. As mddev->gendisk hasn't been set yet, md_open will think something is wrong an return with ERESTARTSYS. This can loop endlessly while the first thread makes no progress through add_disk. Nothing is blocking it, but due to scheduler behaviour it doesn't get a turn. So this is essentially a live-lock. We fix this by simply moving the assignment to mddev->gendisk before the call the add_disk() so md_open doesn't get confused. Also move blk_queue_flush earlier because add_disk should be as late as possible. To make sure that md_open doesn't complete until md_alloc has done all that is needed, we take mddev->open_mutex during the last part of md_alloc. md_open will wait for this. This can cause a lock-up on boot so Cc:ing for stable. For 2.6.36 and earlier a different patch will be needed as the 'blk_queue_flush' call isn't there. Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: Thomas Jarosch <thomas.jarosch@intra2net.com> Tested-by: Thomas Jarosch <thomas.jarosch@intra2net.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit b0140891a8cea36469f58d23859e599b1122bd37 upstream.

There is a race when creating an md device by opening /dev/mdXX.

If two processes do this at much the same time they will follow the
call path
  __blkdev_get -> get_gendisk -> kobj_lookup

The first will call
  -> md_probe -> md_alloc -> add_disk -> blk_register_region

and the race happens when the second gets to kobj_lookup after
add_disk has called blk_register_region but before it returns to
md_alloc.

In the case the second will not call md_probe (as the probe is already
done) but will get a handle on the gendisk, return to __blkdev_get
which will then call md_open (via the ->open) pointer.

As mddev->gendisk hasn't been set yet, md_open will think something is
wrong an return with ERESTARTSYS.

This can loop endlessly while the first thread makes no progress
through add_disk.  Nothing is blocking it, but due to scheduler
behaviour it doesn't get a turn.
So this is essentially a live-lock.

We fix this by simply moving the assignment to mddev->gendisk before
the call the add_disk() so md_open doesn't get confused.
Also move blk_queue_flush earlier because add_disk should be as late
as possible.

To make sure that md_open doesn't complete until md_alloc has done all
that is needed, we take mddev->open_mutex during the last part of
md_alloc.  md_open will wait for this.

This can cause a lock-up on boot so Cc:ing for stable.
For 2.6.36 and earlier a different patch will be needed as the
'blk_queue_flush' call isn't there.

Signed-off-by: NeilBrown <neilb@suse.de>
Reported-by: Thomas Jarosch <thomas.jarosch@intra2net.com>
Tested-by: Thomas Jarosch <thomas.jarosch@intra2net.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
raid5: fix build error, sector_t usage 2011-04-21T17:00:00+00:00 Randy Dunlap randy.dunlap@oracle.com 2011-04-21T16:07:26+00:00 d76c8420c3cf8e468901b0bd58306637335c98ea Change <sectors> from unsigned long long to sector_t. This matches its source field. ERROR: "__udivdi3" [drivers/md/raid456.ko] undefined! Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Change <sectors> from unsigned long long to sector_t.
This matches its source field.

  ERROR: "__udivdi3" [drivers/md/raid456.ko] undefined!

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
md: Cleanup after raid45->raid0 takeover 2011-04-20T05:39:53+00:00 Krzysztof Wojcik krzysztof.wojcik@intel.com 2011-04-20T05:39:53+00:00 fee68723cf6ae00082f70f3eff17fceab2a4f7d7 Problem: After raid4->raid0 takeover operation, another takeover operation (e.g raid0->raid10) results "kernel oops". Root cause: Variables 'degraded' in mddev structure is not cleared on raid45->raid0 takeover. This patch reset this variable. Signed-off-by: Krzysztof Wojcik <krzysztof.wojcik@intel.com> Signed-off-by: NeilBrown <neilb@suse.de> 
Problem:
After raid4->raid0 takeover operation, another takeover operation
(e.g raid0->raid10) results "kernel oops".
Root cause:
Variables 'degraded' in mddev structure is not cleared
on raid45->raid0 takeover.

This patch reset this variable.

Signed-off-by: Krzysztof Wojcik <krzysztof.wojcik@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>