I think that the patch now (3.17-rc1) is upstream but in a slightly modified version:
commit 7f179da0d15ded8f9d56616099f940d50ec582b5 Author: Slava Pestov <email address hidden> Date: Thu May 1 13:48:57 2014 -0700
bcache: fix uninterruptible sleep in writeback thread
I cherry-picked that patch back into Trusty and currently check this in a test VM. The warnings are gone but the load seems to be to high, still.
I think that the patch now (3.17-rc1) is upstream but in a slightly modified version:
commit 7f179da0d15ded8 f9d56616099f940 d50ec582b5
Author: Slava Pestov <email address hidden>
Date: Thu May 1 13:48:57 2014 -0700
bcache: fix uninterruptible sleep in writeback thread
I cherry-picked that patch back into Trusty and currently check this in a test VM. The warnings are gone but the load seems to be to high, still.