CacheFiles: Error: Overlong wait for old active object to go away.
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Medium
|
Unassigned | ||
Trusty |
Fix Released
|
Undecided
|
Unassigned | ||
Xenial |
Fix Released
|
Undecided
|
Unassigned | ||
Bionic |
Fix Released
|
Undecided
|
Unassigned |
Bug Description
== SRU Justification ==
[Impact]
Oops during heavy NFS + FSCache + Cachefiles use:
CacheFiles: Error: Overlong wait for old active object to go away.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000002
CacheFiles: Error: Object already active
kernel BUG at fs/cachefiles/
[Cause]
In a heavily loaded system with big files being read and truncated,
an fscache object for a cookie is being dropped and a new object being looked.
The new object being looked for has to wait for the old object to go away before the
new object is moved to active state.
[Fix]
Clear the flag 'CACHEFILES_
the object lookup.
Remove the BUG() for the case where the old object is still being dropped
and convert to WARN()
[Testcase]
A user has run ~100 hours of NFS stress tests and not seen this bug recur.
[Regression Potential]
- Limited to fscache/cachefiles.
Changed in linux (Ubuntu): | |
importance: | Undecided → Medium |
status: | Incomplete → Triaged |
Changed in linux (Ubuntu Trusty): | |
status: | New → Fix Committed |
Changed in linux (Ubuntu Xenial): | |
status: | New → Fix Committed |
Changed in linux (Ubuntu Bionic): | |
status: | New → Fix Committed |
tags: |
added: kernel-fixup-verification-needed-bionic removed: verification-needed-bionic |
tags: | added: cscc |
This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1776254
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.