CVS commit: src/sys/uvm

[Matthias Drochner <drochner%netbsd.org@localhost>]

Module Name:    src
Committed By:   drochner
Date:           Thu Feb 26 18:18:14 UTC 2009

Modified Files:
        src/sys/uvm: uvm_page.c

Log Message:
-fix two conditions where PQ_FREE was still/already set while the page
 was not anymore/yet on the freelist and uvm_fpageqlock was not held
-clear PQ_FREE while the page is in the works of pageidlezero
This avoids that the DMA memory allocator (pglistalloc) grabs a page
which is not on the freelist, leading to a diagnostic panic (with DEBUG)
or freelist corruption. (mostly on X server activation after a VT
switch or suspend/resume because this can allocate megabytes of AGP
memory)
This might fix PR port-i386/38989 by Alan Barrett (in case this was
a multiprocessor).


To generate a diff of this commit:
cvs rdiff -r1.142 -r1.143 src/sys/uvm/uvm_page.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.