From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gwu.lbox.cz (gwu.lbox.cz [62.245.111.132]) (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 6B8DD3E7145 for ; Sun, 4 Oct 2026 18:46:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.245.111.132 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791139608; cv=none; b=JHsFzTad8YIrN2mHo43VSv6/Ligh54XtGHjBSYDTR90qcDYap22X5rOgZUDWHVlnWai9kcnkKNFytG0zmnMMrJVXb29T+a/0A8XQvYEhyg9loQFibtDmywgyPRtwbnDjtLJYxAn7Zx2iXhQcG2NXx2FMe5EPaAlEPaQSwMO+K2s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791139608; c=relaxed/simple; bh=2napi+fOT3h7MJZDPgiIhPBe22fAMuaFdgmet2FOvoI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=XtN78zIqJTHMZm6dAYMAMMc3xOVb3dnc8sHkF4BeC2IxED90YncAp9PCJfZsgS1n9YAWQPURc9RIWlEZYCOZY2QGg/apfYGbJzIx9VNoZQ5y9Dp/3wNPuMF0DW+mH/PXQYpkke2zI9m6RVL5w7CRE6iEdGUaRlqCvNeGlXnjlTs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linuxbox.cz; spf=pass smtp.mailfrom=linuxbox.cz; dkim=pass (1024-bit key) header.d=linuxbox.cz header.i=@linuxbox.cz header.b=cPsT5ZcH; arc=none smtp.client-ip=62.245.111.132 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linuxbox.cz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linuxbox.cz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxbox.cz header.i=@linuxbox.cz header.b="cPsT5ZcH" Received: from linuxbox.linuxbox.cz (linuxbox.linuxbox.cz [10.76.66.10]) by gwu.lbox.cz (Sendmail) with ESMTPS id 694IjpYK4062391 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sun, 4 Oct 2026 20:45:51 +0200 DKIM-Filter: OpenDKIM Filter v2.11.0 gwu.lbox.cz 694IjpYK4062391 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxbox.cz; s=default; t=1791139553; bh=9HrLouAe+9dAbXUMKxgFdSHX5a0LnpsaBifZX7zcJOM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cPsT5ZcHW36/chAnpDmGiHAT7yG5g4jxV+GDs+8iYhqbX/hH1mXRwGzbJn2+EIHQ7 Fz2NyGs083JF/pboieVHuv1Pepeg2TbjhAJD/ine52TroiGHRt4Qy9ptLk25AyPUXl HHjM/gi/1u0lkd4L6jrlbCLw8KAEpyjx9kk+JGlU= Received: from pcnci.linuxbox.cz (pcnci.linuxbox.cz [10.76.3.14]) by linuxbox.linuxbox.cz (Sendmail) with ESMTPS id 694Ijool022808 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sun, 4 Oct 2026 20:45:50 +0200 Received: from pcnci.linuxbox.cz (localhost [127.0.0.1]) by pcnci.linuxbox.cz (8.18.1/8.15.2) with ESMTPS id 694IjmMx2331923 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Sun, 4 Oct 2026 20:45:50 +0200 Date: Sun, 4 Oct 2026 20:45:48 +0200 From: Nikola Ciprich To: Borislav Petkov Cc: "Lorenzo Stoakes (ARM)" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, david@kernel.org, Mike Rapoport , Dave Hansen , Pedro Falcato , Kiryl Shutsemau , luizcap@redhat.com, pbonzini@redhat.com, Tal Zussman , Rik van Riel , Matt Fleming , Nikola Ciprich Subject: Re: hunting memory corruption bug in 6.18.x Message-ID: References: <20261002220248.GJasAqCFwxOK4l2TbS@fat_crate.local> 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 Content-Transfer-Encoding: 8bit In-Reply-To: <20261002220248.GJasAqCFwxOK4l2TbS@fat_crate.local> X-Scanned-By: MIMEDefang 3.7.1 on 10.76.66.3 X-Scanned-By: MIMEDefang v3.7.1/SpamAssassin v4.000002 on lbxovapx9 (nik) X-Scanned-By: MIMEDefang 2.86 on 10.76.66.10 X-Antivirus: on lbxovapx9 by Antivirus X-Spam-Score: N/A (trusted relay) X-Milter-Copy-Status: O On Fri, Oct 02, 2026 at 03:02:48PM -0700, Borislav Petkov wrote: > On Fri, Oct 02, 2026 at 04:55:39PM +0200, Nikola Ciprich wrote: > > I'll leave it running for few hours, and report back. If I'm able to reproduce, > > I'll try recommended workarounds and report as well. > > I'll venture a guess here and say that Matt's reproducer won't trigger on your > machines. and you're right :( > > Just to rule out any other issues which got fixed in the meantime, can you try > mainline Linux and see if you can reproduce your observation with it? that'll be very complicated in production.. it'd help a lot if we could reproduce it in lab again.. I guess we'll add more windows guests and more load in them and see if we can reproduce it in lab.. > > If so, you could share your crash core along with debug kernels yadda yadda so > that I can poke at it. > > And before you do, make sure you have the latest BIOS and microcode installed on > that machine. > > Also, where can I find full dmesg and /proc/cpuinfo from those machines which > trigger this? I'll gather it all and put it on storage to download tomorrow. cheers nik > > Thx. > > -- > Regards/Gruss, > Boris. > > https://people.kernel.org/tglx/notes-about-netiquette > -- Ing. Nikola CIPRICH technický ředitel +420 591 166 214 +420 777 093 799 nikola.ciprich@linuxbox.cz www.linuxbox.cz