From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from wp530.webpack.hosteurope.de (wp530.webpack.hosteurope.de [80.237.130.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B14F93BBEA; Tue, 16 Apr 2024 06:08:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.237.130.52 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713247698; cv=none; b=pCoDnE8Fvv1EE/PDpHErxpCTACZyrSEs5l8nCjPBtbbBPJDk55hjgoKbzTWqmObfJNJIoa41k71GYeuMiqIRQ5jSTm6x3h/zftMN7yQZoAGMEES7ZQ+/lTW6mmZlUoMwE+vR5UXYTvCTmpx8ENxOFI1V+r+PfvjSs0/Wbs53rj4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713247698; c=relaxed/simple; bh=WICUcYaypsw/DK9gFrMDqKtJd5tnBe1HuVDRQOGmKBc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=f6O2EhC88RwRz/sSNH0pw/s7SkHnwmrC/LzTiAHt+KWQNB6a2ZOppu8iKSEM2clc2ojjUaOi1g2iI33r4gopo0S8evgNlfqsPMvZenoirguI76sfD2fexaavLrx2HVxMPk5u71XW59WmjJw1cFD7HsCUD/nc7N7SIyygAFkZyZU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=leemhuis.info; spf=pass smtp.mailfrom=leemhuis.info; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b=poOdPGFL; arc=none smtp.client-ip=80.237.130.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b="poOdPGFL" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=leemhuis.info; s=he214686; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:From:Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version: Content-Type:Content-Transfer-Encoding:Content-ID:Content-Description: In-Reply-To:References; bh=kokKt0017qNqpH691SbrggxmrEJ7Johu9iji03ZhiK0=; t=1713247696; x=1713679696; b=poOdPGFLnaJdEbeYzfhtLcZr4qniDVpD3ZEVBsES3ap5hUI 8KrF/PPFm/D9PXajLDSEhcmlggJ97wdmCtoy9Iesi2MKNTtRiZpkvC211PZaPdbvGrV6H0uq65M0I K4mSDfv275CY8fLirxdfaK097IUK8Mv1XWNzTMxHp5bm8OgY7CrN6M6P3Ump2MP9nmwsRrpy/T/IE ZXbZc1xdIixqjFm9rQnGKgW3bvNXI46L0/s3IbbgBDfh2S9xGNKLWbiA53qN5eM4W6PB7knd/aTp6 S2/LCXFVQComi20L2rWG/7wH/v6BXsGBnU3fkIuRzsNnOACBGM6atdfxW+8GZ8rg==; Received: from [2a02:8108:8980:2478:8cde:aa2c:f324:937e]; authenticated by wp530.webpack.hosteurope.de running ExIM with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) id 1rwbzE-00032x-Aa; Tue, 16 Apr 2024 08:08:08 +0200 Message-ID: <81149f18-0132-4ace-8c71-1b75790a88e4@leemhuis.info> Date: Tue, 16 Apr 2024 08:08:07 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Bug 218665 - nohz_full=0 prevents kernel from booting To: Tejun Heo Cc: LKML , Bjorn Andersson , Linux regressions mailing list References: <5be248c6-cdda-4d2e-8fae-30fc2cc124c0@leemhuis.info> <28c84b3b-f68f-4f45-8da1-9c3f9a342509@leemhuis.info> <7kugx5ivbplwwrcq5zp37djtpakl55b3pfy36gpbsbcx43dpcs@uheu6iv7gm7h> From: "Linux regression tracking (Thorsten Leemhuis)" Content-Language: en-US, de-DE Reply-To: Linux regressions mailing list In-Reply-To: <7kugx5ivbplwwrcq5zp37djtpakl55b3pfy36gpbsbcx43dpcs@uheu6iv7gm7h> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-bounce-key: webpack.hosteurope.de;regressions@leemhuis.info;1713247696;9626bdd3; X-HE-SMSGID: 1rwbzE-00032x-Aa On 12.04.24 04:57, Bjorn Andersson wrote: > On Wed, Apr 10, 2024 at 11:18:04AM +0200, Linux regression tracking (Thorsten Leemhuis) wrote: >> On 08.04.24 00:52, Bjorn Andersson wrote: >>> On Tue, Apr 02, 2024 at 10:17:16AM +0200, Linux regression tracking (Thorsten Leemhuis) wrote: >>>> >>>> Tejun, apparently it's cause by a change of yours. >>>> Quoting from https://bugzilla.kernel.org/show_bug.cgi?id=218665 : >>>> >>>>> booting the current kernel (6.9.0-rc1, master/712e1425) on x86_64 >>>>> with nohz_full=0 cause a page fault and prevents the kernel from >>>>> booting. >>> [...] Tejun, I got a bit lost here. Can you help me out please? I'm currently assuming that these two reports have the same cause: https://lore.kernel.org/all/20240402105847.GA24832@redhat.com/T/#u https://bugzilla.kernel.org/show_bug.cgi?id=218665 And that both will be fixed by this patch from Oleg Nesterov: https://lore.kernel.org/lkml/20240411143905.GA19288@redhat.com/ But well, to me it looks like below issue from Bjorn is different, even if it is caused by the same change -- nevertheless it looks like nobody has looked into this since it was reported about two weeks ago. Or was progress made and I just missed it? >>> In addition to this report, I have finally bisected another regression >>> to the same commit: >>> >>> I start neovim, send SIGSTOP (i.e. ^Z) to it, start another neovim >>> instance and upon sending SIGSTOP to that instance all of userspace >>> locks up - 100% reproducible. >>> >>> The kernel seems to continue to operate, and tapping the power button >>> dislodge the lockup and I get a clean shutdown. >>> >>> This is seen on multiple Arm64 (Qualcomm) machines with upstream >>> defconfig since commit '5797b1c18919 ("workqueue: Implement system-wide >>> nr_active enforcement for unbound workqueues")'. >> >> Hmmm, I had hoped Tejun would reply and share an opinion if these >> problems are related. But that didn't happen. :-/ So let me at least ask >> one question that might help to answer that question: is the machine >> using CPU isolation, like the two other reports about problems caused by >> this commit do (see the >> https://bugzilla.kernel.org/show_bug.cgi?id=218665 and >> https://lore.kernel.org/all/20240402105847.GA24832@redhat.com/ for >> details) ? > > No, this is a clean SMP system running stock arch/arm64/defconfig, > booted with "clk_ignore_unused pd_ignore_unused audit=0" as the command > line. > > Regards, > Bjorn Ciao, Thorsten