From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from www262.sakura.ne.jp (www262.sakura.ne.jp [202.181.97.72]) (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 E7D6459B62 for ; Tue, 5 Mar 2024 11:31:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.181.97.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709638314; cv=none; b=TXkGbxU9CF4sLQQFLQbf79bUI26umCNpWjcfZvL18n9M+jIV3xyifsG9ylPRr8RCwFYlF9dbAgwUl2W9QTQESJpgCPyFiXJvOlovnkZxCW6ub6mtouFFTRYU3MkF/nbd6nuoqFUZ1J7acg/ZrqSme8HGu9gsgMO443r36HUhsR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709638314; c=relaxed/simple; bh=Eq7aeNGjONd1fpt7pBZhX1cgNq4mlV4aurE5+rGBSUU=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=UBO3E6UW6qmkq21eRVaBWBzn14MmR0pbZ2QqFIKkrNczJkXwso0v2ZKLNIHlOFDeJbL+Tk5femM+n1tAXQeybZJ6fK/hDR4fNdvI/VKWcVMPFrox81tMzDEu+tWkLB/DJ58D7pHR6Zg/owGNMq4TuJMEaaimPvdGNhx/5MS1d1s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=I-love.SAKURA.ne.jp; spf=pass smtp.mailfrom=I-love.SAKURA.ne.jp; arc=none smtp.client-ip=202.181.97.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=I-love.SAKURA.ne.jp Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=I-love.SAKURA.ne.jp Received: from fsav119.sakura.ne.jp (fsav119.sakura.ne.jp [27.133.134.246]) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTP id 425BVEM1099162; Tue, 5 Mar 2024 20:31:14 +0900 (JST) (envelope-from penguin-kernel@I-love.SAKURA.ne.jp) Received: from www262.sakura.ne.jp (202.181.97.72) by fsav119.sakura.ne.jp (F-Secure/fsigk_smtp/550/fsav119.sakura.ne.jp); Tue, 05 Mar 2024 20:31:14 +0900 (JST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/fsav119.sakura.ne.jp) Received: from [192.168.1.6] (M106072142033.v4.enabler.ne.jp [106.72.142.33]) (authenticated bits=0) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTPSA id 425BVDtT099159 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NO); Tue, 5 Mar 2024 20:31:14 +0900 (JST) (envelope-from penguin-kernel@I-love.SAKURA.ne.jp) Message-ID: <06c11112-db64-40ed-bb96-fa02b590a432@I-love.SAKURA.ne.jp> Date: Tue, 5 Mar 2024 20:31:13 +0900 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] x86: disable non-instrumented version of copy_mc when KMSAN is enabled Content-Language: en-US From: Tetsuo Handa To: LKML , the arch/x86 maintainers Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Linus Torvalds References: <3b7dbd88-0861-4638-b2d2-911c97a4cadf@I-love.SAKURA.ne.jp> In-Reply-To: <3b7dbd88-0861-4638-b2d2-911c97a4cadf@I-love.SAKURA.ne.jp> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Ping? This is current top crasher. I hope this patch is applied before the merge window opens. On 2024/03/02 7:52, Tetsuo Handa wrote: > dump_emit_page() caused a false-positive KMSAN warning, for > memcpy_from_iter_mc() is called via iterate_bvec() by setting "struct > iov_iter"->copy_mc to true. > > Fallback to memcpy()/copy_user_generic() when KMSAN is enabled. > > Reported-by: syzbot > Closes: https://syzkaller.appspot.com/bug?extid=d7521c1e3841ed075a42 > Signed-off-by: Tetsuo Handa > Tested-by: syzbot > Reviewed-by: Alexander Potapenko > --- > Changes in v2: > Update description. > > arch/x86/lib/copy_mc.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-)