linux-toradex.git/drivers/md, branch v3.0.34

md: using GFP_NOIO to allocate bio for flush request

2012-06-01T07:12:56+00:00

commit b5e1b8cee7ad58a15d2fa79bcd7946acb592602d upstream.

A flush request is usually issued in transaction commit code path, so
using GFP_KERNEL to allocate memory for flush request bio falls into
the classic deadlock issue.

This is suitable for any -stable kernel to which it applies as it
avoids a possible deadlock.

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

MD: Add del_timer_sync to mddev_suspend (fix nasty panic)

2012-05-21T16:40:03+00:00

commit 0d9f4f135eb6dea06bdcb7065b1e4ff78274a5e9 upstream.

Use del_timer_sync to remove timer before mddev_suspend finishes.

We don't want a timer going off after an mddev_suspend is called.  This is
especially true with device-mapper, since it can call the destructor function
immediately following a suspend.  This results in the removal (kfree) of the
structures upon which the timer depends - resulting in a very ugly panic.
Therefore, we add a del_timer_sync to mddev_suspend to prevent this.

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

md/bitmap: prevent bitmap_daemon_work running while initialising bitmap

2012-04-22T23:21:44+00:00

commit afbaa90b80b1ec66e5137cc3824746bfdf559b18 upstream.

If a bitmap is added while the array is active, it is possible
for bitmap_daemon_work to run while the bitmap is being
initialised.
This is particularly a problem if bitmap_daemon_work sees
bitmap->filemap as non-NULL before it has been filled in properly.
So hold bitmap_info.mutex while filling in ->filemap
to prevent problems.

This patch is suitable for any -stable kernel, though it might not
apply cleanly before about 3.1.

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

dm exception store: fix init error path

2012-04-02T16:27:19+00:00

commit aadbe266f2f89ccc68b52f4effc7b3a8b29521ef upstream.

Call the correct exit function on failure in dm_exception_store_init.

Signed-off-by: Andrei Warkentin 
Acked-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm crypt: add missing error handling

2012-04-02T16:27:19+00:00

commit 72c6e7afc43e19f68a31dea204fc366624d6eee9 upstream.

Always set io->error to -EIO when an error is detected in dm-crypt.

There were cases where an error code would be set only if we finish
processing the last sector. If there were other encryption operations in
flight, the error would be ignored and bio would be returned with
success as if no error happened.

This bug is present in kcryptd_crypt_write_convert, kcryptd_crypt_read_convert
and kcryptd_async_done.

Signed-off-by: Mikulas Patocka 
Reviewed-by: Milan Broz 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm crypt: fix mempool deadlock

2012-04-02T16:27:19+00:00

commit aeb2deae2660a1773c83d3c6e9e6575daa3855d6 upstream.

This patch fixes a possible deadlock in dm-crypt's mempool use.

Currently, dm-crypt reserves a mempool of MIN_BIO_PAGES reserved pages.
It allocates first MIN_BIO_PAGES with non-failing allocation (the allocation
cannot fail and waits until the mempool is refilled). Further pages are
allocated with different gfp flags that allow failing.

Because allocations may be done in parallel, this code can deadlock. Example:
There are two processes, each tries to allocate MIN_BIO_PAGES and the processes
run simultaneously.
It may end up in a situation where each process allocates (MIN_BIO_PAGES / 2)
pages. The mempool is exhausted. Each process waits for more pages to be freed
to the mempool, which never happens.

To avoid this deadlock scenario, this patch changes the code so that only
the first page is allocated with non-failing gfp mask. Allocation of further
pages may fail.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Milan Broz 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

md/raid1,raid10: avoid deadlock during resync/recovery.

2012-04-02T16:27:11+00:00

commit d6b42dcb995e6acd7cc276774e751ffc9f0ef4bf upstream.

If RAID1 or RAID10 is used under LVM or some other stacking
block device, it is possible to enter a deadlock during
resync or recovery.
This can happen if the upper level block device creates
two requests to the RAID1 or RAID10.  The first request gets
processed, blocks recovery and queue requests for underlying
requests in current->bio_list.  A resync request then starts
which will wait for those requests and block new IO.

But then the second request to the RAID1/10 will be attempted
and it cannot progress until the resync request completes,
which cannot progress until the underlying device requests complete,
which are on a queue behind that second request.

So allow that second request to proceed even though there is
a resync request about to start.

This is suitable for any -stable kernel.

Reported-by: Ray Morris 
Tested-by: Ray Morris 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md/bitmap: ensure to load bitmap when creating via sysfs.

2012-04-02T16:27:11+00:00

commit 4474ca42e2577563a919fd3ed782e2ec55bf11a2 upstream.

When commit 69e51b449d383e (md/bitmap:  separate out loading a bitmap...)
created bitmap_load, it missed calling it after bitmap_create when a
bitmap is created through the sysfs interface.
So if a bitmap is added this way, we don't allocate memory properly
and can crash.

This is suitable for any -stable release since 2.6.35.
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

dm raid: fix flush support

2012-03-12T17:33:01+00:00

commit 0ca93de9b789e0eb05e103f0c04de72df13da73a upstream.

Fix dm-raid flush support.

Both md and dm have support for flush, but the dm-raid target
forgot to set the flag to indicate that flushes should be
passed on.  (Important for data integrity e.g. with writeback cache
enabled.)

Signed-off-by: Jonathan Brassow 
Acked-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

dm io: fix discard support

2012-03-12T17:33:01+00:00

commit 0c535e0d6f463365c29623350dbd91642363c39b upstream.

This patch fixes a crash by recognising discards in dm_io.

Currently dm_mirror can send REQ_DISCARD bios if running over a
discard-enabled device and without support in dm_io the system
crashes badly.

BUG: unable to handle kernel paging request at 00800000
IP:  __bio_add_page.part.17+0xf5/0x1e0
...
 bio_add_page+0x56/0x70
 dispatch_io+0x1cf/0x240 [dm_mod]
 ? km_get_page+0x50/0x50 [dm_mod]
 ? vm_next_page+0x20/0x20 [dm_mod]
 ? mirror_flush+0x130/0x130 [dm_mirror]
 dm_io+0xdc/0x2b0 [dm_mod]
...

Introduced in 2.6.38-rc1 by commit 5fc2ffeabb9ee0fc0e71ff16b49f34f0ed3d05b4
(dm raid1: support discard).

Signed-off-by: Milan Broz 
Acked-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman