From: Linus Torvalds Date: Fri, 26 Jan 2007 20:47:06 +0000 (-0800) Subject: Resurrect 'try_to_free_buffers()' VM hackery X-Git-Tag: v2.6.20-rc7~102 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ecdfc9787fe527491baefc22dce8b2dbd5b2908d;p=pandora-kernel.git Resurrect 'try_to_free_buffers()' VM hackery It's not pretty, but it appears that ext3 with data=journal will clean pages without ever actually telling the VM that they are clean. This, in turn, will result in the VM (and balance_dirty_pages() in particular) to never realize that the pages got cleaned, and wait forever for an event that already happened. Technically, this seems to be a problem with ext3 itself, but it used to be hidden by 'try_to_free_buffers()' noticing this situation on its own, and just working around the filesystem problem. This commit re-instates that hack, in order to avoid a regression for the 2.6.20 release. This fixes bugzilla 7844: http://bugzilla.kernel.org/show_bug.cgi?id=7844 Peter Zijlstra points out that we should probably retain the debugging code that this removes from cancel_dirty_page(), and I agree, but for the imminent release we might as well just silence the warning too (since it's not a new bug: anything that triggers that warning has been around forever). Acked-by: Randy Dunlap Acked-by: Jens Axboe Acked-by: Peter Zijlstra Cc: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed