From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id BD0FA6B00AB for ; Tue, 6 Jan 2009 11:16:38 -0500 (EST) Message-ID: <496383E0.50102@ftml.net> Date: Tue, 06 Jan 2009 10:16:32 -0600 From: Roman Kononov MIME-Version: 1.0 Subject: Re: [patch] mm: fix lockless pagecache reordering bug (was Re: BUG: soft lockup - is this XFS problem?) References: <20090105041959.GC367@wotan.suse.de> <20090105064838.GA5209@wotan.suse.de> <49623384.2070801@aon.at> <20090105164135.GC32675@wotan.suse.de> <20090105180008.GE32675@wotan.suse.de> <20090105201258.GN6959@linux.vnet.ibm.com> <20090105215727.GQ6959@linux.vnet.ibm.com> <20090106020550.GA819@wotan.suse.de> In-Reply-To: <20090106020550.GA819@wotan.suse.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Nick Piggin Cc: "Paul E. McKenney" , Linus Torvalds , Peter Klotz , stable@kernel.org, Linux Memory Management List , Christoph Hellwig , Roman Kononov , linux-kernel@vger.kernel.org, xfs@oss.sgi.com, Andrew Morton List-ID: On 2009-01-05 20:05 Nick Piggin said the following: > Subject: mm lockless pagecache barrier fix > static inline void *radix_tree_deref_slot(void **pslot) > { > - void *ret = *pslot; > + void *ret = rcu_dereference(*pslot); > if (unlikely(radix_tree_is_indirect_ptr(ret))) > ret = RADIX_TREE_RETRY; > return ret; 3 systems are working fine for a few hours with the patch. They would fail within 20 minutes without it. Thanks. -- 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/ . Don't email: email@kvack.org