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=-13.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 52B6DC433DB for ; Wed, 24 Feb 2021 18:09:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E0F460201 for ; Wed, 24 Feb 2021 18:09:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233765AbhBXSIt (ORCPT ); Wed, 24 Feb 2021 13:08:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230386AbhBXSIl (ORCPT ); Wed, 24 Feb 2021 13:08:41 -0500 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 247A3C061574 for ; Wed, 24 Feb 2021 10:08:01 -0800 (PST) Received: by mail-pf1-x42c.google.com with SMTP id t29so1820866pfg.11 for ; Wed, 24 Feb 2021 10:08:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=tm7j2omSybNiiT8Csv1rxsiGhueuDiqHKYeICDRJGvk=; b=BXtD87R6wPqyE/17Z0OIrblukbmZY6FkHZPkucn8Jg0M37hYhwIGKd0D7XUX+qzhtt EG8xKa7/YlpUsnAQUFRlfUAglXql3VvGTUtlTrIPV2SDt8C53HJQTbTIuMIdGyzvGQgr eCzBon+W6CypQ+hvstnRkB5WVqy1KjXxa01Zm4bzvP32SN6ugbGKhh1PW7gh9SCZ6iAa 3K+cmFVaVollNaPo90c7Z6IVWWmTaepR+/p6LPh3hvtbcRSusmhO1Em+TmM4+MlK1lo4 8f6p6s3Tr5Ijm8RBmxR7wzd6XhWmtfqGopJ48a92Jm4eHiLBaZyZ/afaNZ/PS6rtCfLD d7mg== 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:references :mime-version:content-disposition:in-reply-to; bh=tm7j2omSybNiiT8Csv1rxsiGhueuDiqHKYeICDRJGvk=; b=cyv0/lpX+pIuenDDEhlOK5JJ/kHNBO4PKoyAcoM98i4YCP8whgat1S7dAIDleTg4t+ x42mmqaIIxSgVZuH/efzavlhuurzjlxMtReZpn/Vv/I71Xzj0VfG2DnZn52pXf0skMfx QpGf+Uy4lu8zCWVAhe9bGznaye0f4s7NpsOXS+HiR6i/P8DYZ/YnuBpJ1qzfesfFwl8D fIeu1iij1FcwNgqaEtKPiPQO2fjFIq6NBy1nBdWGi9e4oORbsWbw+jUOhy6hefS3E5Xj D0qkkavNFmQci04DRBknvwpqUbOrYFFXXFXsuEMX8/lCH6CJG6sDRQdWguvQo/LI0ssk M7IA== X-Gm-Message-State: AOAM530vzPbI6h0XZkArZ62T99CCvoJ8YCY08MvRWR42hv3vpxRu3hX+ neqYscS3wmDmm8/Imag4JSqm+A== X-Google-Smtp-Source: ABdhPJwnP8SclXDpGpjZzVqI/vtae4Z2PJ9dTLzKkzpDyC9Q5If7aIQKga+QnbliG4ce2R09tevDCg== X-Received: by 2002:aa7:848b:0:b029:1ed:5cb9:9e61 with SMTP id u11-20020aa7848b0000b02901ed5cb99e61mr23553561pfn.41.1614190080532; Wed, 24 Feb 2021 10:08:00 -0800 (PST) Received: from google.com ([2620:15c:f:10:385f:4012:d20f:26b5]) by smtp.gmail.com with ESMTPSA id i13sm3427448pfe.46.2021.02.24.10.07.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Feb 2021 10:07:59 -0800 (PST) Date: Wed, 24 Feb 2021 10:07:53 -0800 From: Sean Christopherson To: Borislav Petkov Cc: Dmitry Vyukov , syzbot , Dave Hansen , "H. Peter Anvin" , Jim Mattson , Joerg Roedel , "Kirill A. Shutemov" , KVM list , LKML , Lorenzo Stoakes , Ingo Molnar , Paolo Bonzini , syzkaller-bugs , Thomas Gleixner , Vitaly Kuznetsov , wanpengli@tencent.com, the arch/x86 maintainers Subject: Re: general protection fault in vmx_vcpu_run (2) Message-ID: References: <0000000000007ff56205ba985b60@google.com> <00000000000004e7d105bc091e06@google.com> <20210224122710.GB20344@zn.tnic> <20210224174936.GG20344@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210224174936.GG20344@zn.tnic> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 24, 2021, Borislav Petkov wrote: > Hi Dmitry, > > On Wed, Feb 24, 2021 at 06:12:57PM +0100, Dmitry Vyukov wrote: > > Looking at the bisection log, the bisection was distracted by something else. > > Meaning the bisection result: > > 167dcfc08b0b ("x86/mm: Increase pgt_buf size for 5-level page tables") > > is bogus? Ya, looks 100% bogus. > > You can always find the original reported issue over the dashboard link: > > https://syzkaller.appspot.com/bug?extid=42a71c84ef04577f1aef > > or on lore: > > https://lore.kernel.org/lkml/0000000000007ff56205ba985b60@google.com/ > > Ok, so this looks like this is trying to run kvm ioctls *in* a guest, > i.e., nested. Right? Yep. I tried to run the reproducer yesterday, but the kernel config wouldn't boot my VM. I haven't had time to dig in. Anyways, I think you can safely assume this is a KVM issue unless more data comes along that says otherwise.