Bug 676444 - kswapd stuck in busy loop in nfs_access_cache_shrinker due to bad list manipulation
Summary: kswapd stuck in busy loop in nfs_access_cache_shrinker due to bad list manipu...
Keywords:
Status: CLOSED DUPLICATE of bug 653066
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: kernel
Version: 6.0
Hardware: Unspecified
OS: Unspecified
high
medium
Target Milestone: rc
: ---
Assignee: Red Hat Kernel Manager
QA Contact: Red Hat Kernel QE team
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2011-02-09 21:33 UTC by Casey Dahlin
Modified: 2018-11-14 14:43 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2011-02-21 18:31:07 UTC
Target Upstream Version:

Attachments (Terms of Use)
Patch to replace list_for_each_entry with list_for_each_entry_safe in nfs_access_cache_shrinker (1.17 KB, application/octet-stream)
2011-02-09 21:33 UTC, Casey Dahlin 		no flags Details
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Description Casey Dahlin 2011-02-09 21:33:21 UTC 
Created attachment 477912 [details]
Patch to replace list_for_each_entry with list_for_each_entry_safe in nfs_access_cache_shrinker

Description of problem:
Customer noticed kswapd was getting stuck consuming 100% cpu. Backtraces revealed the culprit to be nfs_access_cache_shrinker. Upstream includes a patch (attached) which corrects a flaw in this function where it uses the wrong list iteration macro to move over the list. It was thus possible for the loop iterator to get "lost" and end up iterating the same now-isolated node over and over forever.

Version-Release number of selected component (if applicable):
kernel 2.6.32-71.el6
Comment 8 Marc Milgram 2011-02-21 18:31:07 UTC 
I noticed that this is already ON QA as part of BZ 653066.

*** This bug has been marked as a duplicate of bug 653066 ***
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