From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932106AbWGGM03 (ORCPT ); Fri, 7 Jul 2006 08:26:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932110AbWGGM03 (ORCPT ); Fri, 7 Jul 2006 08:26:29 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:7431 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S932106AbWGGM03 (ORCPT ); Fri, 7 Jul 2006 08:26:29 -0400 Date: Fri, 7 Jul 2006 14:28:50 +0200 From: Jens Axboe To: Michael Kerrisk Cc: Andrew Morton , michael.kerrisk@gmx.net, linux-kernel@vger.kernel.org Subject: Re: splice/tee bugs? Message-ID: <20060707122850.GU4188@suse.de> References: <20060707070703.165520@gmx.net> <20060707040749.97f8c1fc.akpm@osdl.org> <20060707114235.243260@gmx.net> <20060707120333.GR4188@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060707120333.GR4188@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 07 2006, Jens Axboe wrote: > On Fri, Jul 07 2006, Michael Kerrisk wrote: > > > > c) Occasionally the command line just hangs, producing no output. > > > > In this case I can't kill it with ^C or ^\. This is a > > > > hard-to-reproduce behaviour on my (x86) system, but I have > > > > seen it several times by now. > > > > > > aka local DoS. Please capture sysrq-T output next time. > > > > I don't have sysrq configured in the kernel that I'm testing at > > the moment (I'll build again with sysrq), but have just got > > the error again. For what it's worth, "ps l" says: > > > > F UID PID PPID PRI NI VSZ RSS WCHAN STAT TTY TIME COMMAND > > 0 1000 7099 630 16 0 0 0 - D+ pts/30 0:00 [ktee] > > Try ps -eo cmd,wchan, it should give you a little more at least. But > sysrq-t is the best, of course. > > I'll see about reproducing locally. With your modified ktee, I can reproduce it here. Here's the ktee and wc output: ktee2 D 00000002 0 10027 3182 10028 (L-TLB) f5cd7da0 00000002 f5cd7d8c 00000002 f5cd7d48 c0148c1e f5cd7d58 c18a5914 c03edc80 c19a9f50 00000007 00000000 c1ff1ab0 b5d39d0a 0000003a 067a9ddd c1ff1bc0 c19aa720 00000000 00000000 06d4480b 00000000 c0474880 c0474880 Call Trace: [] __mutex_lock_slowpath+0x95/0x236 [] mutex_lock+0x1c/0x1f [] pipe_read_fasync+0x24/0x57 [] pipe_read_release+0x12/0x23 [] __fput+0x53/0x141 [] fput+0x19/0x1c [] filp_close+0x41/0x67 [] put_files_struct+0xa6/0xb8 [] do_exit+0x124/0x8dd [] do_trap+0x0/0x9e [] do_page_fault+0x274/0x586 [] error_code+0x39/0x40 [] sysenter_past_esp+0x56/0x79 wc D C1DB7F74 0 10028 3182 10027 (NOTLB) c1db7ec8 00000002 c1db7eb4 c1db7f74 00000246 00000101 00000001 00000000 00000003 c1db7f68 00000007 00000001 f6351ab0 af26d8c3 0000003a 0011c727 f6351bc0 c19b2720 00000002 00000044 001ce734 00000000 c0474880 c0474880 Call Trace: [] __mutex_lock_slowpath+0x95/0x236 [] mutex_lock+0x1c/0x1f [] pipe_readv+0x54/0x3a9 [] pipe_read+0x1f/0x21 [] vfs_read+0x85/0xf6 [] sys_read+0x3d/0x64 [] sysenter_past_esp+0x56/0x79 I'll dig around. -- Jens Axboe