Description of problem: Function mark_buffer_dirty() contains SMP-unsafe optimization. If CPU reorders instructions in certain way, it may cause that modified data are not written and filesystem corruption happens. For discussion, see the thread at http://www.uwsg.indiana.edu/hypermail/linux/kernel/0804.0/0854.html There are several possible fixes with different performance and complexity (see the thread), the one that went into upstream kernel is this: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1be62dc190ebaca331038962c873e7967de6cc4b;hp=4ed919014eb2b591eb8fdd4dd00226a65faddef4 Version-Release number of selected component (if applicable): All How reproducible: Can't be reproduced, was found during source code review. If data corruption because of this bug ever happened, it would be very hard to link the corruption to this problem --- so maybe it would be better to fix the bug preemtively.
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-2.6.18-100.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5
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NEC, IBM, others, what is the current status of this bug fix? The fix should be present in the latest RHEL5.3 Snapshot. Please test and send feedback ASAP.
It is fixed in the current 5.3 snapshot. It is fixed with the patch linux-2.6-fs-potential-race-in-mark_buffer_dirty.patch . So any kernels that have this patch have the bug fixed. The bug is hard to trigger (if it was ever triggered at all? --- it was found during source code review), so there is not much to test on it.
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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-2009-0225.html
The needinfo request[s] on this closed bug have been removed as they have been unresolved for 1000 days