From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753492AbcHPQy5 (ORCPT ); Tue, 16 Aug 2016 12:54:57 -0400 Received: from mail-by2nam03on0070.outbound.protection.outlook.com ([104.47.42.70]:28943 "EHLO NAM03-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750749AbcHPQyy (ORCPT ); Tue, 16 Aug 2016 12:54:54 -0400 Authentication-Results: spf=pass (sender IP is 63.163.107.21) smtp.mailfrom=sandisk.com; kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=bestguesspass action=none header.from=sandisk.com; X-AuditID: 0ac94369-b97ff7000001694f-d7-57b34364bb33 Subject: Re: [PATCH] sched: Avoid that __wait_on_bit_lock() hangs To: Oleg Nesterov References: <78fafdc1-d4ae-a9a2-169c-1d456b6e6e41@sandisk.com> <20160809171459.GA13840@redhat.com> <3cec7657-caa9-92ca-9f0e-34f073a6ed8c@sandisk.com> <20160810104555.GA3333@redhat.com> <4d2e02f8-c7da-ee1a-1068-25492cbffebe@sandisk.com> <20160811173651.GA31803@redhat.com> <20160812161611.GC30930@redhat.com> <20160813163208.GA938@redhat.com> <20160816130559.GA14022@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: Date: Tue, 16 Aug 2016 09:54:43 -0700 User-Agent: Mozilla/5.0 (X11; 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Or at least understand what are you doing to > hit this bug ;) Hello Oleg, What I'm doing to hit this bug is to run the test script that is available at https://github.com/bvanassche/srp-test on a setup that is equipped with at least one InfiniBand adapter. I see the following possibilities for you to reproduce this: * Ask a colleague for access to an IB setup. * Add RoCE support to the srp-test script and run that script against a v4.8 kernel + ib_srp-backport + SCST ib_srpt drivers. These last two (out-of-tree) drivers namely support SRP over RoCE. The upstream drivers not yet. The SRP-over-RoCE functionality will be sent upstream as soon as standardization of this protocol by the T10 committee has finished (this work has already been started and will probably be finished later this year). Please let me know if you need more information. Bart.