From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) (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 68A7BC14A for ; Wed, 1 Apr 2026 16:35:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.109.113.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775061316; cv=none; b=ZEa+3oqgqzo2sMaqRtFh+1ncnVTD6HRqhiOxt+lEwAE02WzXS8XWrAYr6NxD7Ij+PoXF470p9DljnofoMJQFk93LKz2Yz35/nsQVt1W46205g4pYICWaietxJGI22zoEZhGwi3TbJtm4Nkfsjqxx7GURzFGLDGnMdESDIPjVIns= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775061316; c=relaxed/simple; bh=R9JQqW4naAkjx1DVMOH2TNhIxtyizT3OE8+rdfq3gQ8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gGbxzS8xZOj78N86o8SyQzdOS6Sqwjd0XqDVj3dXx1zOp5WiApgLprlT/zfyPsgaSaY+Nuk+mJJZajBJ4NANayylJrlH26tMJoMEeZeWYR6padu1xv1GLrzSPKvsVkrKrsQJKJseLGJHYxPN57YoH7bV/xwWlahYvjJpyAxeA78= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de; spf=pass smtp.mailfrom=alien8.de; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b=NTzyJ6jL; arc=none smtp.client-ip=65.109.113.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alien8.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b="NTzyJ6jL" Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 7884740E00DC; Wed, 1 Apr 2026 16:35:11 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id F1ZgjePPJOv1; Wed, 1 Apr 2026 16:35:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1775061306; bh=KMJ4rr0HHAO0x8W3o0hrwtrfV9kaA9Q5i0MDPumFmkM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NTzyJ6jLVptz8rgIDRiiFqEzUvSAmAqPDUmIdr78XFnEeugnzhufptCpT003CVfRL tx8OHzsnHuoq2kJGwKdcQMtC7jz92xIrY2X2+PNkgULwu8RBnFkHGh/liRWHrYm1LV nCJiuud5+Warr0QVKJCFQDQdfMUyiaur35zIBNKa+g0PCHGfePdUlKduQbw+IVP2xt P5bY9wW1M7Y7Vn1+40tUu9vWUtKEGc+cPRKDxh4Qmz3ib9PibWVjtryYRAmfG8ovEY nCBtz587wAaL7bkbredkGuEQNLH2LlFFf61H4d/sOPB+Z9VYydrrtWbAvUdRpOgdJ4 Lg+Ropcz50ePT5UtOaIQ1vwcKGm/xl95VlBqv3lg6UiOdPDgtI/CYYmWGsr3Ll2FOE ngCoIzx9OK+Et5lTDXTTDlZrJl377N2rodGxfZyMA9fPY6cXvSpgOpDtAhR7r+nVlg VSrX8RRLQFa0CqBMrTMXf9H/YFqXUduZXH+FZZheVxVcCrx3XbOHY1BNlmB3uS/4NH quA1K8F9/MWD5TxB/n+/rsYf1+3zIR+ZJfrok5SfJ5k9KXfDRp4JZRDHKnHDy3G9/V 1lwG1AdYhDuQ4dOcQ7UFSINhayniD/2wthmROgJKIyrzFIakb72aLWxYeE+T0urbMa XZZfWvwGhr7xvUdI28Xg/3D8= Received: from zn.tnic (p5de8e020.dip0.t-ipconnect.de [93.232.224.32]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with UTF8SMTPSA id BF69040E015B; Wed, 1 Apr 2026 16:34:40 +0000 (UTC) Date: Wed, 1 Apr 2026 18:34:35 +0200 From: Borislav Petkov To: Thomas Gleixner , Calvin Owens Cc: Petr Mladek , linux-kernel@vger.kernel.org, arighi@nvidia.com, yaozhenguo1@gmail.com, tj@kernel.org, feng.tang@linux.alibaba.com, lirongqing@baidu.com, realwujing@gmail.com, hu.shengming@zte.com.cn, dianders@chromium.org, joel.granados@kernel.org, Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Frederic Weisbecker , Anna-Maria Behnsen , x86@kernel.org Subject: Re: [BUG] Random hard lockup with userspace %ip on 7.0-rc5 Message-ID: <20260401163435.GGac1JG42tWmsCKL37@fat_crate.local> References: <87v7ejetl1.ffs@tglx> <875x6a913n.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <875x6a913n.ffs@tglx> On Wed, Apr 01, 2026 at 05:01:00PM +0200, Thomas Gleixner wrote: > Now that you have a reproducer, can you verify that the machine really > locks up hard? Disable the NMI watchdog either via the kernel command > line 'nmi_watchdog=0' or via echo 0 >/proc/sys/kernel/nmi_watchdog. > > If that works and the machine stays usable then the watchdog is > hallucinating. Yeah, I was able to reproduce here. I am able to Ctrl-C the reproducer so the machine is responsive after that. We'll enable tracing and take it from there. Calvin, thanks for the report - you don't really have to update your BIOS - I can reproduce with the latest. And thanks for the reproducer. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette