From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vyacheslav Dubeyko , Dan Carpenter , Ryusuke Konishi , Andrew Morton , Linus Torvalds Subject: [ 5/9] nilfs2: fix issue with counting number of bio requests for BIO_EOPNOTSUPP error detection Date: Mon, 26 Aug 2013 18:04:56 -0700 Message-Id: <20130827010252.038100984@linuxfoundation.org> In-Reply-To: <20130827010251.636183797@linuxfoundation.org> References: <20130827010251.636183797@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vyacheslav Dubeyko commit 4bf93b50fd04118ac7f33a3c2b8a0a1f9fa80bc9 upstream. Fix the issue with improper counting number of flying bio requests for BIO_EOPNOTSUPP error detection case. The sb_nbio must be incremented exactly the same number of times as complete() function was called (or will be called) because nilfs_segbuf_wait() will call wail_for_completion() for the number of times set to sb_nbio: do { wait_for_completion(&segbuf->sb_bio_event); } while (--segbuf->sb_nbio > 0); Two functions complete() and wait_for_completion() must be called the same number of times for the same sb_bio_event. Otherwise, wait_for_completion() will hang or leak. Signed-off-by: Vyacheslav Dubeyko Cc: Dan Carpenter Acked-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/nilfs2/segbuf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/nilfs2/segbuf.c +++ b/fs/nilfs2/segbuf.c @@ -376,12 +376,12 @@ static int nilfs_segbuf_submit_bio(struc bio->bi_private = segbuf; bio_get(bio); submit_bio(mode, bio); + segbuf->sb_nbio++; if (bio_flagged(bio, BIO_EOPNOTSUPP)) { bio_put(bio); err = -EOPNOTSUPP; goto failed; } - segbuf->sb_nbio++; bio_put(bio); wi->bio = NULL;