This is from an upstream patch:
For some reason it missed being ported into RHEL5. Someone from support reported this bug and promised to open a bz for it. Since that hasn't happened, I'm opening one myself.
The patch is trivial, but quite important.
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Allocation of memory during the write system call can trigger memory reclaim. Without this patch, the VM may call back into the filesystem resulting in an oops. This problem is only seen in times of memory shortage on a node.
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
Created attachment 394762 [details]
Fix for RHEL5
*** Bug 565600 has been marked as a duplicate of this bug. ***
You can download this test kernel from http://people.redhat.com/jwilson/el5
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An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
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