This is a note to let you know that I've just added the patch titled CIFS: Fix a deadlock when a file is reopened to the 3.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: cifs-fix-a-deadlock-when-a-file-is-reopened.patch and it can be found in the queue-3.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 689c3db4d57a73bee6c5ad7797fce7b54d32a87c Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky <pshilovsky@xxxxxxxxx> Date: Thu, 11 Jul 2013 11:17:45 +0400 Subject: CIFS: Fix a deadlock when a file is reopened From: Pavel Shilovsky <pshilovsky@xxxxxxxxx> commit 689c3db4d57a73bee6c5ad7797fce7b54d32a87c upstream. If we request reading or writing on a file that needs to be reopened, it causes the deadlock: we are already holding rw semaphore for reading and then we try to acquire it for writing in cifs_relock_file. Fix this by acquiring the semaphore for reading in cifs_relock_file due to we don't make any changes in locks and don't need a write access. Signed-off-by: Pavel Shilovsky <pshilovsky@xxxxxxxxx> Acked-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Steve French <smfrench@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/cifs/file.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -553,11 +553,10 @@ cifs_relock_file(struct cifsFileInfo *cf struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); int rc = 0; - /* we are going to update can_cache_brlcks here - need a write access */ - down_write(&cinode->lock_sem); + down_read(&cinode->lock_sem); if (cinode->can_cache_brlcks) { - /* can cache locks - no need to push them */ - up_write(&cinode->lock_sem); + /* can cache locks - no need to relock */ + up_read(&cinode->lock_sem); return rc; } @@ -568,7 +567,7 @@ cifs_relock_file(struct cifsFileInfo *cf else rc = tcon->ses->server->ops->push_mand_locks(cfile); - up_write(&cinode->lock_sem); + up_read(&cinode->lock_sem); return rc; } Patches currently in stable-queue which might be from pshilovsky@xxxxxxxxx are queue-3.10/cifs-fix-a-deadlock-when-a-file-is-reopened.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html