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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 697E7C4321E for ; Tue, 29 Nov 2022 11:26:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232965AbiK2L0r (ORCPT ); Tue, 29 Nov 2022 06:26:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229650AbiK2L0n (ORCPT ); Tue, 29 Nov 2022 06:26:43 -0500 X-Greylist: delayed 400 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 29 Nov 2022 03:26:41 PST Received: from us.icdsoft.com (us.icdsoft.com [192.252.146.184]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E9364B775 for ; Tue, 29 Nov 2022 03:26:40 -0800 (PST) Received: (qmail 26958 invoked by uid 1001); 29 Nov 2022 11:20:00 -0000 Received: from unknown (HELO ?94.155.37.249?) (famzah@icdsoft.com@94.155.37.249) by 192.252.159.165 with ESMTPA; 29 Nov 2022 11:20:00 -0000 Message-ID: Date: Tue, 29 Nov 2022 13:19:41 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: [tip: x86/fpu] x86/fpu/xstate: Define new functions for clearing fpregs and xstates Content-Language: en-US To: Thomas Gleixner , "Yu, Yu-cheng" , Andy Lutomirski , LKML Cc: linux-tip-commits@vger.kernel.org, Fenghua Yu , Borislav Petkov , Dave Hansen , Tony Luck , x86 , "Shankar, Ravi V" References: <20200512145444.15483-6-yu-cheng.yu@intel.com> <158964181793.17951.15480349640697746223.tip-bot2@tip-bot2> <10a553a5-699f-6921-705e-9afa1a8e42de@intel.com> <87y2c28zir.ffs@nanos.tec.linutronix.de> From: Ivan Zahariev In-Reply-To: <87y2c28zir.ffs@nanos.tec.linutronix.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello gentlemen, Hello Yu-cheng Yu, Can you please take a look into this bug which syzbot tracked to a commit of yours (b860eb8dce5906b14e3a7f3c771e0b3d6ef61b94). Even since we switched from kernel 4.14 to 5.15 we are experiencing often random segmentation faults with the following error in "dmesg":    post.sh[2237] bad frame in rt_sigreturn frame:00007ad24b2f8df8 ip:733cfa4351d1 sp:7ad24b2f9398 orax:ffffffffffffffff in libc-2.28.so[733cfa36d000+147000] Most commonly Bash is getting hit by this problem but other binaries also experience the it less often. Thomas Gleixner has already provided some insight and a simple reproducer: https://groups.google.com/g/syzkaller-bugs/c/rbdQkahfwE4/m/RyWIrlA0BQAJ If there is no simple fix, can we simply revert the faulty commit? Best regards. --Ivan