From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752470AbcHHSbb (ORCPT ); Mon, 8 Aug 2016 14:31:31 -0400 Received: from mail-bl2nam02on0086.outbound.protection.outlook.com ([104.47.38.86]:59456 "EHLO NAM02-BL2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751479AbcHHSb3 (ORCPT ); Mon, 8 Aug 2016 14:31:29 -0400 Authentication-Results: spf=pass (sender IP is 63.163.107.21) smtp.mailfrom=sandisk.com; suse.de; dkim=none (message not signed) header.d=none;suse.de; dmarc=bestguesspass action=none header.from=sandisk.com; X-AuditID: ac160c69-5dfff70000000bcb-68-57a8ce18d428 Subject: Re: [PATCH] sched: Avoid that __wait_on_bit_lock() hangs To: Oleg Nesterov References: <20160803181128.GH6879@twins.programming.kicks-ass.net> <11007730-3fa5-139a-8091-655743894ae8@sandisk.com> <20160803213006.GA11712@redhat.com> <17b65ff9-215f-ab74-9f5f-15dbd308d054@sandisk.com> <20160804140938.GB24652@twins.programming.kicks-ass.net> <16207b90-2e6c-fe23-1b4b-3763e5cf0384@sandisk.com> <20160808102213.GA6879@twins.programming.kicks-ass.net> <4091e252-18d9-1795-de63-9fbc678aa6b1@acm.org> <20160808162038.GA25927@redhat.com> CC: Peter Zijlstra , "mingo@kernel.org" , Andrew Morton , "Johannes Weiner" , Neil Brown , Michael Shaver , "linux-kernel@vger.kernel.org" From: Bart Van Assche Message-ID: <78fafdc1-d4ae-a9a2-169c-1d456b6e6e41@sandisk.com> Date: Mon, 8 Aug 2016 11:31:19 -0700 User-Agent: Mozilla/5.0 (X11; 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Hello Oleg, No external modules were loaded when I triggered the lockup I mentioned in the patch description. Although the SRP test software I referred to earlier can be run against the SCST SRP target driver, I'm using the in-tree LIO SRP target driver to reproduce this lockup. BTW, I think it is unlikely that the target driver framework is involved in the lockup since I have observed this lockup before when no SRP target driver was loaded on the test system. The same lockup also has already been observed with md-raid. Thanks, Bart.