From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2AAFC06511 for ; Tue, 2 Jul 2019 11:40:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C800E21721 for ; Tue, 2 Jul 2019 11:40:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=mvista-com.20150623.gappssmtp.com header.i=@mvista-com.20150623.gappssmtp.com header.b="Mr/LFjeF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727039AbfGBLkd (ORCPT ); Tue, 2 Jul 2019 07:40:33 -0400 Received: from mail-ot1-f67.google.com ([209.85.210.67]:46278 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725858AbfGBLkc (ORCPT ); Tue, 2 Jul 2019 07:40:32 -0400 Received: by mail-ot1-f67.google.com with SMTP id z23so16792250ote.13 for ; Tue, 02 Jul 2019 04:40:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mvista-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=UZfV2K+vRYovbEmc4xW7M1m9m9UVMdISiH4IGr65Si4=; b=Mr/LFjeFjw7cM6DFoT/rxsSW5RZSb+dKMgku3GcGQdxop8pLBt2PCjuJOGB0DnKGr8 y+eel+EX1BM6oTsftcMzwx6/ym9BvPEAJL/nt9xVUq2HnjNO3yEGnOjbmJWAhIQoqiqG tlLmeztHo601FwmlOmlZcXXdyI3kS7zYxAdXSARtTSIj5FdNSNUDltufKQShSRo+/imn pl0PghOGttHdahEkBAbT+g0JPj7F6b3PMwkBY96PzbG1Qf1WEwBk3DCKhREmCF0YKbw0 HzL5RDljRgCLjNekj+KA8N7aU5ViICFg9xXw9SeX8dhrCmBbSJd0b2y/hdpFt1M2ahpa O1Jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:reply-to :references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=UZfV2K+vRYovbEmc4xW7M1m9m9UVMdISiH4IGr65Si4=; b=of68zQODsyr6efcGf4JTqq4MzU/I0lPkKKEGrUYPNNTpGZO/FeSAlohWX9UV0sd8iC cwcCc6L9bTYts2JkgMqbCOIHH/2wFlbCOSgPX9WCjGUiK3EImALv9VjYnBn1iwvO9cfi nTH4KOmfXvX2N1M/vzWfUgITk7wjvzCLevC0D7nXYjvlC/sOjzQqC8pwK+/LmZPm1TzF TUiet17LuRyAZibTFyU8TTnq3nKu+BmP5K0nvp5Lhik0CTwok7mb6AAUHS09otyDoWoe a7DZpPtYdDiL8RAGsxrleE0oOCEpOq627raOZIJG3EbBANvNx9r4N7fOF2jgdkdifzWD c0+g== X-Gm-Message-State: APjAAAU/d3tlgbSVAvL5c+qLn3rszDnpq/3tFuOuEqxR0F0u2A5xznOQ JavrpSj82UrbL+7KZtPE2WrnXQ== X-Google-Smtp-Source: APXvYqzCF2ozBteJsHr5zFDBDsymWiXtSW4SlZ6y2apRXBV5YzsVBF5ktI7w2WTAb24no37gXJLlgg== X-Received: by 2002:a9d:4b95:: with SMTP id k21mr25701582otf.281.1562067631380; Tue, 02 Jul 2019 04:40:31 -0700 (PDT) Received: from minyard.net ([2001:470:b8f6:1b:9575:16b6:1dd6:2173]) by smtp.gmail.com with ESMTPSA id q2sm5171073oia.45.2019.07.02.04.40.29 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 02 Jul 2019 04:40:30 -0700 (PDT) Date: Tue, 2 Jul 2019 06:40:28 -0500 From: Corey Minyard To: Sebastian Andrzej Siewior Cc: Kurt Kanzenbach , Steven Rostedt , Corey Minyard , linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Zijlstra , tglx@linutronix.de Subject: Re: [PATCH RT v2] Fix a lockup in wait_for_completion() and friends Message-ID: <20190702114028.GE5041@minyard.net> Reply-To: cminyard@mvista.com References: <20190510103318.6cieoifz27eph4n5@linutronix.de> <20190628214903.6f92a9ea@oasis.local.home> <20190701190949.GB4336@minyard.net> <20190701161840.1a53c9e4@gandalf.local.home> <20190701204325.GD5041@minyard.net> <20190701170602.2fdb35c2@gandalf.local.home> <20190701171333.37cc0567@gandalf.local.home> <20190701172825.7d861e85@gandalf.local.home> <20190702070418.h6ynkkgk6v6s3aii@linutronix.de> <20190702083536.vt346ysqmq6q23iz@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190702083536.vt346ysqmq6q23iz@linutronix.de> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 02, 2019 at 10:35:36AM +0200, Sebastian Andrzej Siewior wrote: > On 2019-07-02 09:04:18 [+0200], Kurt Kanzenbach wrote: > > > In fact, my system doesn't boot with this commit in 5.0-rt. > > > > > > If I revert 90e1b18eba2ae4a729 ("swait: Delete the task from after a > > > wakeup occured") the machine boots again. > > > > > > Sebastian, I think that's a bad commit, please revert it. > > > > I'm having the same problem on a Cyclone V based ARM board. Reverting > > this commit solves the boot issue for me as well. > > Okay. So the original Corey fix as in v5.0.14-rt9 works for everyone. > Peter's version as I picked it up for v5.0.21-rt14 is causing problems > for two persons now. > > I'm leaning towards reverting it back to old version for now… Just to avoid confusion... it wasn't my patch 1921ea799b7dc56 (sched/completion: Fix a lockup in wait_for_completion()) that caused the issue, nor was it Peter's version of it. Instead, it was the patch mentioned above, 90e1b18eba2ae4a729 ("swait: Delete the task from after a wakeup occured"), which came from someone else. I can verify by visual inspection that that patch is broken and it should definitely be removed. Just don't want someone to be confused and remove the wrong patch. -corey > > > Thanks, > > Kurt > > Sebastian