From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f43.google.com (mail-ej1-f43.google.com [209.85.218.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C9D626BFC0; Thu, 17 Oct 2024 03:39:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.43 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729136387; cv=none; b=a1YyqyAd1BWlMQC1O7jIlM62M5CsJ3cTzMk98VaM3S/MHy0LM51j4b/E/z5dtrhzhPG4cOTvAyREIfQ+99nhOwsIyDSk8WOvPBgmvgSlrA8DGCvyRIjkUmg7Uaaa/mnvIxl2NfGLA/RGR3IhDLaDBXZL4sFYrfr12ApjTR04Drc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729136387; c=relaxed/simple; bh=ll9KNLkVW5eVQ/kDk1KI8rxOkRgzBSrnu0RG0fEV+3E=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=gVpEKO0dBYPRO3Yew4Q24sVSK8dl4yOv0t5B3yzHl/lFkyvWaFwe6OTorxXimfiCzt+a3uwjxAGGclkwPMvQa9idh0b7Iyr8GWR6AyAfGezVD1DgSxBJFB0YlKWHTcGACY7x1S/Rek048Gl5NAEpYUE0ORdR0J7+dI3z2Omw9XE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=fTbpkvOz; arc=none smtp.client-ip=209.85.218.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fTbpkvOz" Received: by mail-ej1-f43.google.com with SMTP id a640c23a62f3a-a9a039511a7so8511366b.0; Wed, 16 Oct 2024 20:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1729136384; x=1729741184; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=s0tI51HOKytW0kcq7yTi5a60pKE5OoOTWRqkx7pSWOg=; b=fTbpkvOzLBSy04lj874IymwEgOyA5GlqtVRgZivUKdguXkqkFaCLPHMmfcAm0h+DBz ae8WuTCiL3b1b2XUGRgHzwo03P5wdqVgyUYXGBteTxl7IOxv8l5vxWZhVPXNT6ebAMjz n7fo6Sv11hIZ9Ajl42FIw/XaD6zozxxJuke/nnbUhrr/I96YXyCpQHGjmgH2hXY6nTo1 PZuvNObGNL8zkLcrDapIOtgAZin9rirqCKFcXHHfxPeMqaGkShiSyyyBQhO7/tYSNC45 HV/FUouyQAClUK5Z/pLIpsoGz9Kd+ev7q/+uOsJym5x1ot2tWo47+V5fySeXMOzk7G/6 dbnQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729136384; x=1729741184; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=s0tI51HOKytW0kcq7yTi5a60pKE5OoOTWRqkx7pSWOg=; b=RIIps9K0+exjAqwc8Gml/TvYhQU72+tokL8tw5iWBMQo2z8zjV3NL0ctKAhJ93FkZG 4mJlQMpnXJpyksLtPGyuvnRwiCGUJTvNMlKeX2ot+Viec68O8QnTpoQcqoPEVWG2WQ7x USLiQuVFbW12iWzsbokLk/56ItLFM99RayI6xCGoOW2BRGGDFIQld/EmE4Pu3oAYXTtV balqyzOM8Rpc4TEGTS51tMQjnxs/NE/KzNj2Z+Bl53qUn2orO2WD8V/+pbUdkP1r3/Af ioLDL14z3hDL41dQWw6z/AcfwYJuowvsu6CuQ/QcyP5YBvjNAbMXXfNGbXeFIhIydtLC pX1g== X-Forwarded-Encrypted: i=1; AJvYcCUbHL964fabDckmuB5iowThZfj/nq7j9GoW/sGmQxKpIEU3IUXmm2YFT/O5eNA+WynaQAJXTf+ym91Ksb1/@vger.kernel.org, AJvYcCV7bqd7CjSZYm8LiJy4pg6sqC2F12oQJz1/dzfrIYLpT+EY0smRJqfz28i+owGYIz39KbnOAIM6pw==@vger.kernel.org X-Gm-Message-State: AOJu0Yw8UOybnq3J5/qxWDpmGAPGh5R6r6EP1rEb1gv8dxKQZr/aA13s 6CcOzwMavVw1fMUZr5dtQUnfcXLJbWAEkWCItQzWVyQGluDs97MJ6oJli7hIDW+hxio9yM+Fex/ UkpXyZWJNZVc61XfzJjNJZOcwMlk= X-Google-Smtp-Source: AGHT+IHH6ahqEN9cRcWFEfqUSV84Ayz569JIzcrs+n+rLrJme226TWECzbw+PiLJSqEUz1VBBWJLV0pzol9WtZq58GA= X-Received: by 2002:a05:6402:40d1:b0:5c9:3f3:ae0 with SMTP id 4fb4d7f45d1cf-5c9a5e76c7bmr451534a12.5.1729136383905; Wed, 16 Oct 2024 20:39:43 -0700 (PDT) Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <15c0859f-445f-4159-9b38-3af6d9a2a572@intel.com> In-Reply-To: <15c0859f-445f-4159-9b38-3af6d9a2a572@intel.com> From: Marius Fleischer Date: Wed, 16 Oct 2024 20:39:31 -0700 Message-ID: Subject: Re: WARNING in get_pat_info To: Dave Hansen Cc: Jens Axboe , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , linux-kernel@vger.kernel.org, syzkaller@googlegroups.com, harrisonmichaelgreen@gmail.com, Pavel Begunkov , io-uring@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Hi Dave, > > TL;DR compile syzkaller, copy syz-execprog, syz-executor, repro.syz into > > the VM and run the command below inside the VM > > ./syz-execprog -executor=./syz-executor -procs=8 -repeat=0 repro.syz > > > > Please let me know if you need more details from us! > > It didn't reproduce for me, either, at least ~10k executed programs in. > How long should it take? > This is surprising to me - it triggers the crash within 4 seconds for me. syz-execprog should not even get to the state of printing the number of executed programs. Could you try compiling an older version of syzkaller, specifically the commit bf285f0cf1f7863e0b0d17980de703fab89476bb? I noticed that the instructions I linked to above mention that a difference in syzkaller version can lead to issues. Not sure if this is relevant, but I am using the bullseye image created with the script provided by syzkaller as described here https://github.com/google/syzkaller/blob/master/docs/linux/setup_ubuntu-host_qemu-vm_x86-64-kernel.md#image. > The next step would be to figure out specifically why get_pat_info() > failed. To double check that io_uring is the thing that's involved and > (presumably) why follow_phys() failed. Basically, I think we need to > know what state the page tables and the VMA were in. Sorry, I am very inexperienced in debugging such crashes. Could you expand a little bit on what state of page tables and VMA exactly means? Are there some specific kernel structs I should dump? Best, Marius