Note to self:
The commit being backported to 3.19 and 3.13 has to contain this race
fix:
commit dcc909d90ccdbb73226397ff6d298f7af35b0e11
Author: Markus Pargmann <m...@pengutronix.de>
Date: Tue Oct 6 20:03:54 2015 +0200
nbd: Add locking for tasks
The timeout handling introduced in
7e2893a16d3e (nbd: Fix timeout detection)
introduces a race condition which may lead to killing of tasks that are
not in nbd context anymore. This was not observed or reproducable yet.
This patch adds locking to critical use of task_recv and task_send to
avoid killing tasks that already left the NBD thread functions. This
lock is only acquired if a timeout occures or the nbd device
starts/stops.
Reported-by: Ben Hutchings <b...@decadent.org.uk>
Signed-off-by: Markus Pargmann <m...@pengutronix.de>
Reviewed-by: Ben Hutchings <b...@decadent.org.uk>
Fixes: 7e2893a16d3e ("nbd: Fix timeout detection")
Signed-off-by: Jens Axboe <ax...@fb.com>
Also.
** Patch removed: "trusty-nbd-restructure-debugging-prints.patch"
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1505564/+attachment/4524366/+files/trusty-nbd-restructure-debugging-prints.patch
** Patch removed: "trusty-nbd-fix-timeout-detection.patch"
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1505564/+attachment/4524367/+files/trusty-nbd-fix-timeout-detection.patch
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Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1505564
Title:
Soft lockup with "block nbdX: Attempted send on closed socket" spam
Status in linux package in Ubuntu:
In Progress
Bug description:
Some of our nova compute hosts regularly freeze, sometimes for a few
hours, with kern.log getting spammed with:
block nbdX: Attempted send on closed socket
and a few "CPU soft lockup" messages (see attached log). This clears
up when the queue gets cleared, eg :
block nbdX: queue cleared
trusty hosts with kernel version 3.19.0-30-generic.
To manage notifications about this bug go to:
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