Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757101Ab1DLUXd (ORCPT ); Tue, 12 Apr 2011 16:23:33 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:34199 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756370Ab1DLUXc convert rfc822-to-8bit (ORCPT ); Tue, 12 Apr 2011 16:23:32 -0400 MIME-Version: 1.0 In-Reply-To: References: <20110412182809.GA1218@redhat.com> <20110412192059.GA14360@redhat.com> From: Linus Torvalds Date: Tue, 12 Apr 2011 13:22:39 -0700 Message-ID: Subject: Re: Processes hang in an unkillable state To: =?UTF-8?B?Um9iZXJ0IMWad2nEmWNraQ==?= Cc: Oleg Nesterov , =?ISO-8859-1?Q?Am=E9rico_Wang?= , linux-kernel@vger.kernel.org, Hugh Dickins , Miklos Szeredi Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1130 Lines: 25 On Tue, Apr 12, 2011 at 1:03 PM, Robert Święcki wrote: >> >> Ok, applied Linus' patch and got the following (kdb dump in the attachment): >> >> It contains references to sys_mlock, but in another process/user that >> oopsed (there are iknowthis and iknowthis2 processes running under >> test and test2 users). I think I'll simply disable sys_madvise in the >> fuzzer; and treat this oops as a separate issue. This does seem to be something else. It looks like some kind of live-lock situation between two processes both doing madvise() and causing vmtruncate_range() calls. Miklos wrote this patch for something bad in this area to serialize concurrent unmap_mapping_range() calls in order to not restart forever on vm_truncate_count. That got merged into 2.6.38, so it's there, but I wonder if there is some case it misses. Linus -- 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/