From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 D7D941C7B79; Fri, 25 Oct 2024 09:53:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729850033; cv=none; b=ZPEvB0jCIYcdW9wZbw+Lw0C7ZTiOAGqk9CWVDWFFkSY5gZ4PUFG7dnNleG5QIAmHuJF6vRqg8cD1Zr/LSHnK5RSQQ7eMIQv84XDQ/MxIZLgUs0JODDT4H3xw7qXBlabd/gErXVAxko/AF14d8A9hWZAlvg2olW/Ah8HVGWAB4g4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729850033; c=relaxed/simple; bh=W5EQbHTC6EziqGrCsV7nFc+6r14CHxbg0BJscd8yHJQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dd/oDb/yZAvN2ZvXoK6bgsuSf0I6PHObj+hBcK3wk4FotPDmrtiXJQBcCI8oBI5jkWgVvQaBUJfEtemWiYHHznGjvEfoSmRRom/+HfGvVTqnbmCoqaOv/LwPKzK5oeQfWJz6d3lmLJGZUj1kcdchLEwMTuOkPrio6wrwmbbLcg4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=USPL3rpC; arc=none smtp.client-ip=192.198.163.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="USPL3rpC" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1729850032; x=1761386032; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=W5EQbHTC6EziqGrCsV7nFc+6r14CHxbg0BJscd8yHJQ=; b=USPL3rpCJ4SCQZHm+xliou75MjU9jz83eNTR925GDeDPoW9xnFGKYuLq Yx5fOEvjPAQhcTFJR9YXZlzV9nUtSfRsfR6/qcaX0I+xomG2hrQLeYWwe rEFTLWeyv1LV3faUjQPBgEgn67AiyqUbCEpj0ofunyKWwouNu0R/93/L7 TE4l6xtDwed7NUU1yT/FnyTph+0wTQJ03bjn1SJGlI84HoRYJp0EmIlZv XOLiXfJFB2CtJH2uX3NfTI+vjzuar9nGU63s/fFVLyRD2Wf11cpa3wZ27 K845HzFJnaObYHdzikWNI3358QJlq5c2+JGY70AjfPOO5oV9p1bw88L1C A==; X-CSE-ConnectionGUID: gLwlJBE0TwuzNtSXQbXzDA== X-CSE-MsgGUID: 0/UPtWGZSkSQHJNa41K00w== X-IronPort-AV: E=McAfee;i="6700,10204,11235"; a="54916912" X-IronPort-AV: E=Sophos;i="6.11,231,1725346800"; d="scan'208";a="54916912" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2024 02:53:51 -0700 X-CSE-ConnectionGUID: D4XZ1wtrQHyLHkgqq15yhg== X-CSE-MsgGUID: xhQSCP+KTruksCryxb/9pg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,231,1725346800"; d="scan'208";a="80879699" Received: from ly-workstation.sh.intel.com (HELO ly-workstation) ([10.239.161.23]) by fmviesa009-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2024 02:53:50 -0700 Date: Fri, 25 Oct 2024 17:52:57 +0800 From: "Lai, Yi" To: Kent Overstreet Cc: linux-bcachefs@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [Syzkaller & bisect] There is INFO: task hung in __rq_qos_throttle Message-ID: References: Precedence: bulk X-Mailing-List: linux-bcachefs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Oct 23, 2024 at 09:57:53PM -0400, Kent Overstreet wrote: > On Mon, Oct 21, 2024 at 06:27:25PM +0800, Lai, Yi wrote: > > Hi Kent Overstreet, > > > > Greetings! > > > > I used Syzkaller and found that there is INFO: task hung in __rq_qos_throttle in v6.12-rc2 > > > > After bisection and the first bad commit is: > > " > > 63332394c7e1 bcachefs: Move snapshot table size to struct snapshot_table > > You sure...? > > Look at the patch, that's a pretty unlikely culprit; we would've seen > something from kasan, and anyways there's guards on the new memory > accesses/array derefs. > > I've been seeing that bug too, but it's very intermittent. How did you > get it to trigger reliably enough for a bisect? Look into my local bisection log. You are right, that the bug is intermittent and takes a very long time to reproduce the issue. I didn't observe similar issues during following v6.12-rcx kernel fuzzing. I will keep monitoring. Regards, Yi Lai