Description of problem: Root filesystem went read-only after do_get_write_access() encountered a memory failure. do_get_write_access: OOM for frozen_buffer ext3_reserve_inode_write: aborting transaction: Out of memory in __ext3_journal_get_write_access EXT3-fs error (device dm-0) in ext3_reserve_inode_write: Out of memory Aborting journal on device dm-0. EXT3-fs error (device dm-0) in ext3_dirty_inode: Out of memory ext3_abort called. EXT3-fs error (device dm-0): ext3_journal_start_sb: Detected aborted journal Remounting filesystem read-only There was a lot of oomkiller activity around the time this happened. Version-Release number of selected component (if applicable): kernel-2.6.18-92.1.13.el5PAE How reproducible: Customer has seen this a few times. Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info: I did some digging through the code and found this suspect bit in __alloc_pages() added by patch linux-2.6-mm-oom-prevent-from-killing-several-processes.patch from BZ 392351. --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -994,6 +994,8 @@ nofail_alloc: goto nopage; rebalance: + if (test_thread_flag(TIF_MEMDIE)) + goto nopage; cond_resched(); /* We now go into synchronous reclaim */ I'm pretty sure that if a thread tagged with TIF_MEMDIE (which means it has been targetted by the oomkiller) enters this code with __GFP_NOFAIL it can fail to honour that flag and return with NULL. Maybe the original problem from BZ 392351 could instead be fixed with: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=b43a57bb4dae72e8f7232e7c821a8799eda30022 which wont have this new bug.
Updating priority to reflect issue status.
Created attachment 363038 [details] Patch to fix this problem The attached patch fixes this problem by not bailing out of __alloc_pages if __GFP_NOFAIL was passed in.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
in kernel-2.6.18-174.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5 Please do NOT transition this bugzilla state to VERIFIED until our QE team has sent specific instructions indicating when to do so. However feel free to provide a comment indicating that this fix has been verified.
~~ Attention Customers and Partners - RHEL 5.5 Beta is now available on RHN ~~ RHEL 5.5 Beta has been released! There should be a fix present in this release that addresses your request. Please test and report back results here, by March 3rd 2010 (2010-03-03) or sooner. Upon successful verification of this request, post your results and update the Verified field in Bugzilla with the appropriate value. If you encounter any issues while testing, please describe them and set this bug into NEED_INFO. If you encounter new defects or have additional patch(es) to request for inclusion, please clone this bug per each request and escalate through your support representative.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2010-0178.html