commit d35bd764e6899a7bea71958f08d16cea5bfa1919 upstream.
Add cond_resched() to a loop that fills in the mapper memory area
because the loop can be executed many times.
Fixes: 48debafe4f2fe ("dm: add writecache target")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 31b22120194b5c0d460f59e0c98504de1d3f1f14 upstream.
The dm-writecache reads metadata in the target constructor. However, when
we reload the target, there could be another active instance running on
the same device. This is the sequence of operations when doing a reload:
1. construct new target
2. suspend old target
3. resume new target
4. destroy old target
Metadata that were written by the old target between steps 1 and 2 would
not be visible by the new target.
Fix the data corruption by loading the metadata in the resume handler.
Also, validate block_size is at least as large as both the devices'
logical block size and only read 1 block from the metadata during
target constructor -- no need to read entirety of metadata now that it
is done during resume.
Fixes: 48debafe4f2f ("dm: add writecache target")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1edaa447d958bec24c6a79685a5790d98976fd16 upstream.
Initializing a dm-writecache device can take a long time when the
persistent memory device is large. Add cond_resched() to a few loops
to avoid warnings that the CPU is stuck.
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mikulas Patocka