Messages in this thread Patch in this message | | | Date | Tue, 10 Oct 2006 10:14:25 -0700 | From | Greg KH <> | Subject | [patch 02/19] NFS: Fix a potential deadlock in nfs_release_page |
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-stable review patch. If anyone has any objections, please let us know.
------------------ From: Nikita Danilov <nikita@clusterfs.com>
nfs_wb_page() waits on request completion and, as a result, is not safe to be called from nfs_release_page() invoked by VM scanner as part of GFP_NOFS allocation. Fix possible deadlock by analyzing gfp mask and refusing to release page if __GFP_FS is not set.
Signed-off-by: Nikita Danilov <danilov@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- fs/nfs/file.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- linux-2.6.17.13.orig/fs/nfs/file.c +++ linux-2.6.17.13/fs/nfs/file.c @@ -325,7 +325,13 @@ static void nfs_invalidate_page(struct p static int nfs_release_page(struct page *page, gfp_t gfp) { - return !nfs_wb_page(page->mapping->host, page); + if (gfp & __GFP_FS) + return !nfs_wb_page(page->mapping->host, page); + else + /* + * Avoid deadlock on nfs_wait_on_request(). + */ + return 0; } struct address_space_operations nfs_file_aops = { -- - 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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