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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 27E1BC10F03 for ; Thu, 25 Apr 2019 09:04:10 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E91CD214C6 for ; Thu, 25 Apr 2019 09:04:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="XV0/3TkH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E91CD214C6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7O3UHnVAwwKWGDyR97VzpUZs4aO3RHVKZvFj4BKZ7QY=; b=XV0/3TkHAvyFbu TX3dLwQCx8yRlwz3RUSe+GpRcH6VaK2agfi3wTYHp8jKGWBFXawE4hOHBkh5LvfoyYPMPQ5MaE305 U1SWPKEr7hxHJQYVvJPxGUE6HUlCTXU/2rem73U5Nnrbpr5F/AMV3WyfHvKGTSbHRQlUEC7Ae1DNa wpbDlxBwfLRbwWNt7rdF7wYbjTTPkE0hCbkBcKGnN9Nfc/ARw/Vo+e8S9oloQyOi32JOzrFmqSZKw oydgAl5bpHsr4brqKhFU1B0xO631oDTKfmzVrhs15j+gCui7KLOh4vhyi8+AOO9C3q3B1Zd4cHNZC vixpnVNQYDVhes2pLV3g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hJaIb-0008Oz-4u; Thu, 25 Apr 2019 09:04:09 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hJaIX-0008Oc-TS for linux-arm-kernel@lists.infradead.org; Thu, 25 Apr 2019 09:04:07 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 04A16A78; Thu, 25 Apr 2019 02:04:01 -0700 (PDT) Received: from e107155-lin (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DC6063F5AF; Thu, 25 Apr 2019 02:03:59 -0700 (PDT) Date: Thu, 25 Apr 2019 10:03:57 +0100 From: Sudeep Holla To: Jean-Philippe Brucker Subject: Re: [PATCH] drivers/firmware: psci_checker: Park kthreads before stopping them Message-ID: <20190425090357.GB1535@e107155-lin> References: <20190424174728.13826-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190424174728.13826-1-jean-philippe.brucker@arm.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190425_020405_971967_9710EEA8 X-CRM114-Status: GOOD ( 24.83 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, linux-arm-kernel@lists.infradead.org, Sudeep Holla Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Jean-Philippe, Thanks for fixing this, I did see this issue when I was working on commit 7401056de5f8 ("drivers/firmware: psci_checker: stash and use topology_core_cpumask for hotplug tests") but was not consistent. On Wed, Apr 24, 2019 at 06:47:28PM +0100, Jean-Philippe Brucker wrote: > Since commit 85f1abe0019f ("kthread, sched/wait: Fix kthread_parkme() > completion issue"), kthreads that are bound to a CPU must be parked > before being stopped. At the moment the PSCI checker calls > kthread_stop() directly on the suspend kthread, which triggers the > following warning: > > [ 6.068288] WARNING: CPU: 1 PID: 1 at kernel/kthread.c:398 __kthread_bind_mask+0x20/0x78 > ... > [ 6.190151] Call trace: > [ 6.192566] __kthread_bind_mask+0x20/0x78 > [ 6.196615] kthread_unpark+0x74/0x80 > [ 6.200235] kthread_stop+0x44/0x1d8 > [ 6.203769] psci_checker+0x3bc/0x484 > [ 6.207389] do_one_initcall+0x48/0x260 > [ 6.211180] kernel_init_freeable+0x2c8/0x368 > [ 6.215488] kernel_init+0x10/0x100 > [ 6.218935] ret_from_fork+0x10/0x1c > [ 6.222467] ---[ end trace e05e22863d043cd3 ]--- > > kthread_unpark() tries to bind the thread to its CPU and aborts with a > WARN() if the thread wasn't in TASK_PARKED state. Park the kthreads > before stopping them. > > Fixes: 85f1abe0019f ("kthread, sched/wait: Fix kthread_parkme() completion issue") Now that this file along with psci.c is move into drivers/firmware/psci/ you may have to repost. The changes are in linux-next and may land upstream via linux-pm tree. I assume we can get this merged as fix after merge window ? FWIW, Reviewed-by: Sudeep Holla > Signed-off-by: Jean-Philippe Brucker > --- > See also 060586324648 ("io_uring: park SQPOLL thread if it's percpu") > for a similar fix. > --- > drivers/firmware/psci_checker.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/firmware/psci_checker.c b/drivers/firmware/psci_checker.c > index 346943657962..cbd53cb1b2d4 100644 > --- a/drivers/firmware/psci_checker.c > +++ b/drivers/firmware/psci_checker.c > @@ -366,16 +366,16 @@ static int suspend_test_thread(void *arg) > for (;;) { > /* Needs to be set first to avoid missing a wakeup. */ > set_current_state(TASK_INTERRUPTIBLE); > - if (kthread_should_stop()) { > - __set_current_state(TASK_RUNNING); > + if (kthread_should_park()) > break; > - } > schedule(); > } > > pr_info("CPU %d suspend test results: success %d, shallow states %d, errors %d\n", > cpu, nb_suspend, nb_shallow_sleep, nb_err); > > + kthread_parkme(); > + > return nb_err; > } > > @@ -440,8 +440,10 @@ static int suspend_tests(void) > > > /* Stop and destroy all threads, get return status. */ > - for (i = 0; i < nb_threads; ++i) > + for (i = 0; i < nb_threads; ++i) { > + err += kthread_park(threads[i]); > err += kthread_stop(threads[i]); > + } > out: > cpuidle_resume_and_unlock(); > kfree(threads); > -- > 2.21.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel