Description of problem:
Include all the upstream dm-thin commits through 3.15:
a9d4539 dm transaction manager: fix corruption due to non-atomic transaction commit
fe76cd8 dm thin: fix dangling bio in process_deferred_bios error path
760fe67 dm thin: simplify pool_is_congested
c140e1c dm thin: use per thin device deferred bio lists
67324ea dm thin: sort the per thin deferred bios using an rb_tree
5e3283e dm thin: irqsave must always be used with the pool->lock spinlock
b10ebd3 dm thin: fix rcu_read_lock being held in code that can sleep
fbcde3d dm thin: use INIT_WORK_ONSTACK in noflush_work to avoid ODEBUG warning
NOTE: A couple other 3.15 dm-thin fixes are going in through bug#1091852 and bug#1095639, specifically:
8d07e8a dm thin: allow metadata commit if pool is in PM_OUT_OF_DATA_SPACE mode
85ad643 dm thin: add timeout to stop out-of-data-space mode holding IO forever
First 2 commits listed in comment#0 are already in RHEL7:
a9d4539 dm transaction manager: fix corruption due to non-atomic transaction commit
fe76cd8 dm thin: fix dangling bio in process_deferred_bios error path
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://rhn.redhat.com/errata/RHSA-2015-0290.html