From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755158AbaHFHvc (ORCPT ); Wed, 6 Aug 2014 03:51:32 -0400 Received: from mail-qg0-f45.google.com ([209.85.192.45]:41293 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753799AbaHFHva (ORCPT ); Wed, 6 Aug 2014 03:51:30 -0400 MIME-Version: 1.0 In-Reply-To: <20140805130646.GZ19379@twins.programming.kicks-ass.net> References: <20140804103025.478913141@infradead.org> <20140805130646.GZ19379@twins.programming.kicks-ass.net> Date: Wed, 6 Aug 2014 11:51:29 +0400 Message-ID: Subject: Re: [RFC][PATCH 0/7] nested sleeps, fixes and debug infra From: Ilya Dryomov To: Peter Zijlstra Cc: Ingo Molnar , oleg@redhat.com, Linus Torvalds , tglx@linutronix.de, Mike Galbraith , Linux Kernel Mailing List , netdev@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 5, 2014 at 5:06 PM, Peter Zijlstra wrote: > On Tue, Aug 05, 2014 at 12:33:16PM +0400, Ilya Dryomov wrote: >> On Mon, Aug 4, 2014 at 2:30 PM, Peter Zijlstra wrote: >> > Hi, >> > >> > Ilya recently tripped over a nested sleep which made Ingo suggest we should >> > have debug checks for that. So I did some, see patch 7. Of course that >> > triggered a whole bunch of fail the instant I tried to boot my machine. >> > >> > With this series I can boot my test box and build a kernel on it, I'm fairly >> > sure that's far too limited a test to have found all, but its a start. >> >> FWIW, I'm getting a lot of these during light rbd testing. CC'ed >> netdev and linux-mm. > > Both are cond_resched() calls, and that's not blocking as such, just a > preemption point, so lets exclude those. OK, this one is a bit different. WARNING: CPU: 1 PID: 1744 at kernel/sched/core.c:7104 __might_sleep+0x58/0x90() do not call blocking ops when !TASK_RUNNING; state=1 set at [] prepare_to_wait+0x50 /0xa0 Modules linked in: CPU: 1 PID: 1744 Comm: lt-ceph_test_li Not tainted 3.16.0-vm+ #113 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 0000000000001bc0 ffff88006c4479d8 ffffffff8156f455 0000000000000000 ffff88006c447a28 ffff88006c447a18 ffffffff81033357 0000000000000001 0000000000000000 0000000000000950 ffffffff817ee48a ffff88006dba6120 Call Trace: [] dump_stack+0x4f/0x7c [] warn_slowpath_common+0x87/0xb0 [] warn_slowpath_fmt+0x41/0x50 [] ? trace_hardirqs_on_caller+0x182/0x1f0 [] ? prepare_to_wait+0x50/0xa0 [] ? prepare_to_wait+0x50/0xa0 [] __might_sleep+0x58/0x90 [] lock_sock_nested+0x31/0xb0 [] ? release_sock+0x1bb/0x200 [] sk_stream_wait_memory+0x18a/0x2d0 [] ? woken_wake_function+0x10/0x10 [] tcp_sendmsg+0xb6f/0xd70 [] inet_sendmsg+0xdf/0x100 [] ? inet_recvmsg+0x100/0x100 [] sock_sendmsg+0x67/0x90 [] ? might_fault+0x51/0xb0 [] ___sys_sendmsg+0x2d2/0x2e0 [] ? do_dup2+0xd0/0xd0 [] ? do_dup2+0xd0/0xd0 [] ? finish_task_switch+0x50/0x100 [] ? __fget_light+0x45/0x60 [] ? __fdget+0xe/0x10 [] __sys_sendmsg+0x44/0x70 [] SyS_sendmsg+0x9/0x10 [] system_call_fastpath+0x16/0x1b Thanks, Ilya From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ilya Dryomov Subject: Re: [RFC][PATCH 0/7] nested sleeps, fixes and debug infra Date: Wed, 6 Aug 2014 11:51:29 +0400 Message-ID: References: <20140804103025.478913141@infradead.org> <20140805130646.GZ19379@twins.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Ingo Molnar , oleg@redhat.com, Linus Torvalds , tglx@linutronix.de, Mike Galbraith , Linux Kernel Mailing List , netdev@vger.kernel.org, linux-mm@kvack.org To: Peter Zijlstra Return-path: In-Reply-To: <20140805130646.GZ19379@twins.programming.kicks-ass.net> Sender: owner-linux-mm@kvack.org List-Id: netdev.vger.kernel.org On Tue, Aug 5, 2014 at 5:06 PM, Peter Zijlstra wrote: > On Tue, Aug 05, 2014 at 12:33:16PM +0400, Ilya Dryomov wrote: >> On Mon, Aug 4, 2014 at 2:30 PM, Peter Zijlstra wrote: >> > Hi, >> > >> > Ilya recently tripped over a nested sleep which made Ingo suggest we should >> > have debug checks for that. So I did some, see patch 7. Of course that >> > triggered a whole bunch of fail the instant I tried to boot my machine. >> > >> > With this series I can boot my test box and build a kernel on it, I'm fairly >> > sure that's far too limited a test to have found all, but its a start. >> >> FWIW, I'm getting a lot of these during light rbd testing. CC'ed >> netdev and linux-mm. > > Both are cond_resched() calls, and that's not blocking as such, just a > preemption point, so lets exclude those. OK, this one is a bit different. WARNING: CPU: 1 PID: 1744 at kernel/sched/core.c:7104 __might_sleep+0x58/0x90() do not call blocking ops when !TASK_RUNNING; state=1 set at [] prepare_to_wait+0x50 /0xa0 Modules linked in: CPU: 1 PID: 1744 Comm: lt-ceph_test_li Not tainted 3.16.0-vm+ #113 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 0000000000001bc0 ffff88006c4479d8 ffffffff8156f455 0000000000000000 ffff88006c447a28 ffff88006c447a18 ffffffff81033357 0000000000000001 0000000000000000 0000000000000950 ffffffff817ee48a ffff88006dba6120 Call Trace: [] dump_stack+0x4f/0x7c [] warn_slowpath_common+0x87/0xb0 [] warn_slowpath_fmt+0x41/0x50 [] ? trace_hardirqs_on_caller+0x182/0x1f0 [] ? prepare_to_wait+0x50/0xa0 [] ? prepare_to_wait+0x50/0xa0 [] __might_sleep+0x58/0x90 [] lock_sock_nested+0x31/0xb0 [] ? release_sock+0x1bb/0x200 [] sk_stream_wait_memory+0x18a/0x2d0 [] ? woken_wake_function+0x10/0x10 [] tcp_sendmsg+0xb6f/0xd70 [] inet_sendmsg+0xdf/0x100 [] ? inet_recvmsg+0x100/0x100 [] sock_sendmsg+0x67/0x90 [] ? might_fault+0x51/0xb0 [] ___sys_sendmsg+0x2d2/0x2e0 [] ? do_dup2+0xd0/0xd0 [] ? do_dup2+0xd0/0xd0 [] ? finish_task_switch+0x50/0x100 [] ? __fget_light+0x45/0x60 [] ? __fdget+0xe/0x10 [] __sys_sendmsg+0x44/0x70 [] SyS_sendmsg+0x9/0x10 [] system_call_fastpath+0x16/0x1b Thanks, Ilya -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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