Messages in this thread | | | Date | Tue, 10 Oct 2006 12:30:27 -0700 | From | Andrew Morton <> | Subject | Re: [stable] [patch 07/19] invalidate_complete_page() race fix |
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On Tue, 10 Oct 2006 12:14:18 -0700 Greg KH <greg@kroah.com> wrote:
> On Tue, Oct 10, 2006 at 07:12:54PM +0100, Hugh Dickins wrote: > > On Tue, 10 Oct 2006, Greg KH wrote: > > > > > -stable review patch. If anyone has any objections, please let us know. > > > > > > ------------------ > > > From: Andrew Morton <akpm@osdl.org> > > > > > > If a CPU faults this page into pagetables after invalidate_mapping_pages() > > > checked page_mapped(), invalidate_complete_page() will still proceed to remove > > > the page from pagecache. This leaves the page-faulting process with a > > > detached page. If it was MAP_SHARED then file data loss will ensue. > > > > > > Fix that up by checking the page's refcount after taking tree_lock. > > > > I may have lost the plot, but I think this patch has already proved > > to cause problems for NFS in 2.6.18: not good to put it into 2.6.17 > > stable while it's awaiting refinement for 2.6.18 stable. > > Ok, I've dropped it now. >
It needs invalidate_inode_pages2-ignore-page-refcounts.patch as well.
This patch (invalidate_complete_page() race fix) fixes a cramfs unmount race and, iirc, a pagefault-vs-invalidate race which Nick was seeing. So applying both patches would make 2.6.17 a better place, but we could live without them. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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