Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755598Ab3JGQWv (ORCPT ); Mon, 7 Oct 2013 12:22:51 -0400 Received: from mail-wg0-f48.google.com ([74.125.82.48]:65478 "EHLO mail-wg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751634Ab3JGQWu convert rfc822-to-8bit (ORCPT ); Mon, 7 Oct 2013 12:22:50 -0400 MIME-Version: 1.0 Date: Mon, 7 Oct 2013 18:22:48 +0200 Message-ID: Subject: Deadlock (un-killable processes) in sys_futex From: =?UTF-8?B?Um9iZXJ0IMWad2nEmWNraQ==?= To: linux-kernel@vger.kernel.org, linux-mm@kvack.org 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: 1429 Lines: 38 After fuzzing the linux kernel (3.12-rc4) I have two processes which are stuck in an un-killable state. This is not specific to 3.12-rc4, as I'm able to reproduce it on most modern kernels (e.g. Ubuntu's 3.5) after a few minutes of fuzzing with a syscall fuzzer. The debug data can be found here: http://alt.swiecki.net/linux/20327/ - process PIDs: 20327 and 13735 It includes.. ftrace report (probably the most useful): I'm not expert in this kernel area (futex/mm), but it seems like a constatnt loop between fault_in_user_writeable() and do_page_fault(): http://alt.swiecki.net/linux/20327/20327.trace.report.txt /proc/pid/maps, /proc/pid/status: http://alt.swiecki.net/linux/20327/20327.maps.txt http://alt.swiecki.net/linux/20327/20327.status.txt kdb stacktraces showing that both processes (single-threaded) are stuck in sys_futex: http://alt.swiecki.net/linux/20327/20327.kdb.txt http://alt.swiecki.net/linux/20327/13735.kdb.txt kgdb stacktraces displaying rather corrupted data: http://alt.swiecki.net/linux/20327/20327.kgdb.txt http://alt.swiecki.net/linux/20327/13735.kgdb.txt kernel conf: http://alt.swiecki.net/linux/20327/config-3.12-rc4.txt -- Robert Święcki -- 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/