From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id B5B55900001 for ; Sat, 30 Apr 2011 22:35:38 -0400 (EDT) Received: from hpaq3.eem.corp.google.com (hpaq3.eem.corp.google.com [172.25.149.3]) by smtp-out.google.com with ESMTP id p412Za4v022016 for ; Sat, 30 Apr 2011 19:35:36 -0700 Received: from pve37 (pve37.prod.google.com [10.241.210.37]) by hpaq3.eem.corp.google.com with ESMTP id p412ZVRE004403 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Sat, 30 Apr 2011 19:35:35 -0700 Received: by pve37 with SMTP id 37so3901411pve.35 for ; Sat, 30 Apr 2011 19:35:31 -0700 (PDT) Date: Sat, 30 Apr 2011 19:35:38 -0700 (PDT) From: Hugh Dickins Subject: [PATCH] mmotm: fix hang at startup In-Reply-To: <201104300002.p3U02Ma2026266@imap1.linux-foundation.org> Message-ID: References: <201104300002.p3U02Ma2026266@imap1.linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Christoph Hellwig , Wu Fengguang , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Yesterday's mmotm hangs at startup, and with lockdep it reports: BUG: spinlock recursion on CPU#1, blkid/284 - with bdi_lock_two() called from bdev_inode_switch_bdi() in the backtrace. It appears that this function is sometimes called with new the same as old. Signed-off-by: Hugh Dickins --- Fix to writeback-split-inode_wb_list_lock-into-bdi_writebacklist_lock.patch fs/block_dev.c | 2 ++ 1 file changed, 2 insertions(+) --- 2.6.39-rc5-mm1/fs/block_dev.c 2011-04-29 18:20:09.183314733 -0700 +++ linux/fs/block_dev.c 2011-04-30 17:55:45.718785263 -0700 @@ -57,6 +57,8 @@ static void bdev_inode_switch_bdi(struct { struct backing_dev_info *old = inode->i_data.backing_dev_info; + if (dst == old) + return; bdi_lock_two(&old->wb, &dst->wb); spin_lock(&inode->i_lock); inode->i_data.backing_dev_info = dst; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org