linux-toradex.git/drivers/md, branch v3.14.7

md: always set MD_RECOVERY_INTR when interrupting a reshape thread.

2014-06-11T18:54:11+00:00

commit 2ac295a544dcae9299cba13ce250419117ae7fd1 upstream.

Commit 8313b8e57f55b15e5b7f7fc5d1630bbf686a9a97
   md: fix problem when adding device to read-only array with bitmap.

added a called to md_reap_sync_thread() which cause a reshape thread
to be interrupted (in particular, it could cause md_thread() to never even
call md_do_sync()).
However it didn't set MD_RECOVERY_INTR so ->finish_reshape() would not
know that the reshape didn't complete.

This only happens when mddev->ro is set and normally reshape threads
don't run in that situation.  But raid5 and raid10 can start a reshape
thread during "run" is the array is in the middle of a reshape.
They do this even if ->ro is set.

So it is best to set MD_RECOVERY_INTR before abortingg the
sync thread, just in case.

Though it rare for this to trigger a problem it can cause data corruption
because the reshape isn't finished properly.
So it is suitable for any stable which the offending commit was applied to.
(3.2 or later)

Fixes: 8313b8e57f55b15e5b7f7fc5d1630bbf686a9a97
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: always set MD_RECOVERY_INTR when aborting a reshape or other "resync".

2014-06-11T18:54:11+00:00

commit 3991b31ea072b070081ca3bfa860a077eda67de5 upstream.

If mddev->ro is set, md_to_sync will (correctly) abort.
However in that case MD_RECOVERY_INTR isn't set.

If a RESHAPE had been requested, then ->finish_reshape() will be
called and it will think the reshape was successful even though
nothing happened.

Normally a resync will not be requested if ->ro is set, but if an
array is stopped while a reshape is on-going, then when the array is
started, the reshape will be restarted.  If the array is also set
read-only at this point, the reshape will instantly appear to success,
resulting in data corruption.

Consequently, this patch is suitable for any -stable kernel.

Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

dm cache: always split discards on cache block boundaries

2014-06-11T18:54:10+00:00

commit f1daa838e861ae1a0fb7cd9721a21258430fcc8c upstream.

The DM cache target cannot cope with discards that span multiple cache
blocks, so each discard bio that spans more than one cache block must
get split by the DM core.

Signed-off-by: Heinz Mauelshagen 
Acked-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm thin: add 'no_space_timeout' dm-thin-pool module param

2014-06-11T18:54:10+00:00

commit 80c578930ce77ba8bcfb226a184b482020bdda7b upstream.

Commit 85ad643b ("dm thin: add timeout to stop out-of-data-space mode
holding IO forever") introduced a fixed 60 second timeout.  Users may
want to either disable or modify this timeout.

Allow the out-of-data-space timeout to be configured using the
'no_space_timeout' dm-thin-pool module param.  Setting it to 0 will
disable the timeout, resulting in IO being queued until more data space
is added to the thin-pool.

Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm thin: add timeout to stop out-of-data-space mode holding IO forever

2014-06-07T17:28:25+00:00

commit 85ad643b7e7e52d37620fb272a9fd577a8095647 upstream.

If the pool runs out of data space, dm-thin can be configured to
either error IOs that would trigger provisioning, or hold those IOs
until the pool is resized.  Unfortunately, holding IOs until the pool is
resized can result in a cascade of tasks hitting the hung_task_timeout,
which may render the system unavailable.

Add a fixed timeout so IOs can only be held for a maximum of 60 seconds.
If LVM is going to resize a thin-pool that is out of data space it needs
to be prompt about it.

Signed-off-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm thin: allow metadata commit if pool is in PM_OUT_OF_DATA_SPACE mode

2014-06-07T17:28:25+00:00

commit 8d07e8a5f5bc7b90f755d9b427ea930024f4c986 upstream.

Commit 3e1a0699 ("dm thin: fix out of data space handling") introduced
a regression in the metadata commit() method by returning an error if
the pool is in PM_OUT_OF_DATA_SPACE mode.  This oversight caused a thin
device to return errors even if the default queue_if_no_space ENOSPC
handling mode is used.

Fix commit() to only fail if pool is in PM_READ_ONLY or PM_FAIL mode.

Reported-by: qindehua@163.com
Signed-off-by: Joe Thornber 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

dm crypt: fix cpu hotplug crash by removing per-cpu structure

2014-06-07T17:28:25+00:00

commit 610f2de3559c383caf8fbbf91e9968102dff7ca0 upstream.

The DM crypt target used per-cpu structures to hold pointers to a
ablkcipher_request structure.  The code assumed that the work item keeps
executing on a single CPU, so it didn't use synchronization when
accessing this structure.

If a CPU is disabled by writing 0 to /sys/devices/system/cpu/cpu*/online,
the work item could be moved to another CPU.  This causes dm-crypt
crashes, like the following, because the code starts using an incorrect
ablkcipher_request:

 smpboot: CPU 7 is now offline
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000130
 IP: [] crypt_convert+0x12d/0x3c0 [dm_crypt]
 ...
 Call Trace:
  [] ? kcryptd_crypt+0x305/0x470 [dm_crypt]
  [] ? finish_task_switch+0x40/0xc0
  [] ? process_one_work+0x168/0x470
  [] ? worker_thread+0x10b/0x390
  [] ? manage_workers.isra.26+0x290/0x290
  [] ? kthread+0xaf/0xc0
  [] ? kthread_create_on_node+0x120/0x120
  [] ? ret_from_fork+0x7c/0xb0
  [] ? kthread_create_on_node+0x120/0x120

Fix this bug by removing the per-cpu definition.  The structure
ablkcipher_request is accessed via a pointer from convert_context.
Consequently, if the work item is rescheduled to a different CPU, the
thread still uses the same ablkcipher_request.

This change may undermine performance improvements intended by commit
c0297721 ("dm crypt: scale to multiple cpus") on select hardware.  In
practice no performance difference was observed on recent hardware.  But
regardless, correctness is more important than performance.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer 
Signed-off-by: Greg Kroah-Hartman

md: avoid possible spinning md thread at shutdown.

2014-06-07T17:28:12+00:00

commit 0f62fb220aa4ebabe8547d3a9ce4a16d3c045f21 upstream.

If an md array with externally managed metadata (e.g. DDF or IMSM)
is in use, then we should not set safemode==2 at shutdown because:

1/ this is ineffective: user-space need to be involved in any 'safemode' handling,
2/ The safemode management code doesn't cope with safemode==2 on external metadata
   and md_check_recover enters an infinite loop.

Even at shutdown, an infinite-looping process can be problematic, so this
could cause shutdown to hang.

Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md/raid10: call wait_barrier() for each request submitted.

2014-06-07T17:28:12+00:00

commit cc13b1d1500656a20e41960668f3392dda9fa6e2 upstream.

wait_barrier() includes a counter, so we must call it precisely once
(unless balanced by allow_barrier()) for each request submitted.

Since
commit 20d0189b1012a37d2533a87fb451f7852f2418d1
    block: Introduce new bio_split()
in 3.14-rc1, we don't call it for the extra requests generated when
we need to split a bio.

When this happens the counter goes negative, any resync/recovery will
never start, and  "mdadm --stop" will hang.

Reported-by: Chris Murphy 
Fixes: 20d0189b1012a37d2533a87fb451f7852f2418d1
Cc: Kent Overstreet 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

dm cache: fix writethrough mode quiescing in cache_map

2014-06-07T17:28:12+00:00

commit 131cd131a9ff63d4b84f3fe15073a2984ac30066 upstream.

Commit 2ee57d58735 ("dm cache: add passthrough mode") inadvertently
removed the deferred set reference that was taken in cache_map()'s
writethrough mode support.  Restore taking this reference.

This issue was found with code inspection.

Signed-off-by: Mike Snitzer 
Acked-by: Joe Thornber 
Signed-off-by: Greg Kroah-Hartman