From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752485AbaKWSiY (ORCPT ); Sun, 23 Nov 2014 13:38:24 -0500 Received: from mail.skyhub.de ([78.46.96.112]:44529 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752453AbaKWSiV (ORCPT ); Sun, 23 Nov 2014 13:38:21 -0500 Date: Sun, 23 Nov 2014 19:38:18 +0100 From: Borislav Petkov To: Oleg Nesterov Cc: lkml , Rik van Riel , Peter Zijlstra , Steven Rostedt , x86-ml Subject: Re: task_stat splat Message-ID: <20141123183818.GA6032@pd.tnic> References: <20141123111220.GA6436@pd.tnic> <20141123172256.GA9625@redhat.com> <20141123175641.GA11619@redhat.com> <20141123181717.GA13198@redhat.com> <20141123182108.GA15349@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20141123182108.GA15349@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 23, 2014 at 07:21:08PM +0100, Oleg Nesterov wrote: > > Perhaps this is migration thread? stop_sched_class doesn't have ->update_curr. > > Yes, I think this can explain the problem, but > > > could you try to cat /proc/pid-of-migration-thread/stat on your machine? > > This won't trigger the crash unless it is running. This ? $ for pid in $(pgrep migration); do cat /proc/$pid/stat; done 10 (migration/0) S 2 0 0 0 -1 69238848 0 0 0 0 0 10 0 0 -100 0 1 0 8 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 0 99 1 0 0 0 0 0 0 0 0 0 0 0 13 (migration/1) S 2 0 0 0 -1 69238848 0 0 0 0 0 4 0 0 -100 0 1 0 9 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 1 99 1 0 0 0 0 0 0 0 0 0 0 0 18 (migration/2) S 2 0 0 0 -1 69238848 0 0 0 0 0 4 0 0 -100 0 1 0 11 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 2 99 1 0 0 0 0 0 0 0 0 0 0 0 23 (migration/3) S 2 0 0 0 -1 69238848 0 0 0 0 0 10 0 0 -100 0 1 0 14 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 3 99 1 0 0 0 0 0 0 0 0 0 0 0 28 (migration/4) S 2 0 0 0 -1 69238848 0 0 0 0 0 4 0 0 -100 0 1 0 16 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 4 99 1 0 0 0 0 0 0 0 0 0 0 0 33 (migration/5) S 2 0 0 0 -1 69238848 0 0 0 0 0 11 0 0 -100 0 1 0 19 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 5 99 1 0 0 0 0 0 0 0 0 0 0 0 38 (migration/6) S 2 0 0 0 -1 69238848 0 0 0 0 0 10 0 0 -100 0 1 0 21 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 6 99 1 0 0 0 0 0 0 0 0 0 0 0 43 (migration/7) S 2 0 0 0 -1 69238848 0 0 0 0 0 6 0 0 -100 0 1 0 23 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 7 99 1 0 0 0 0 0 0 0 0 0 0 0 It doesn't trigger, of course, as I've reverted the patch. Second resume looks ok. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --