On 3/26/18 10:39 PM, Omar Sandoval wrote:

From: Omar Sandoval <redacted>

Hi, Jens,

We hit an issue where a loop device on NFS (yes, I know) got stuck and a
bunch of losetup processes got stuck in uninterruptible sleep waiting
for lo_ctl_mutex as a result. Calling into the filesystem while holding
lo_ctl_mutex isn't necessary, and there's no reason to be
uninterruptible here. These two patches fix this issue, based on your
for-next branch.

Applied for 4.17, thanks Omar.

-- 
Jens Axboe