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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_NONE 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 7F2A3C47088 for ; Wed, 26 May 2021 22:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5FF15613B0 for ; Wed, 26 May 2021 22:03:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233218AbhEZWEo (ORCPT ); Wed, 26 May 2021 18:04:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51804 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233037AbhEZWEi (ORCPT ); Wed, 26 May 2021 18:04:38 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA6D5C061574 for ; Wed, 26 May 2021 15:03:06 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1622066583; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UTohWqh3CSUGUskeJH4858GrTk9b2+xV1h3FHXzjaSU=; b=wTn6lXcSZYO2TFFgWrM2WXXKKx47TL0MrnqKsGIxkwrr5hdRVf57DDva3YhYKiVkvdpEzl 5t5Arh+vgdrUUYVMHTXEU4oLtZAcdABbCVEkBrf0sEWylbYztyBnJ5wf+qKn1zBqDc3epC 5B13ZIv4PqQyDHvZijrf97yDZLlgJNzX76AioSXJN0AiRMnnP05rlhHavLhdRWA6IvTxEj bXk4yneKWFzYJshPRijClnYRxjq78odRTj8kk4no9fUCUKl1euiAIC4jMi9Tdy+5bphvcR 6fDXCzPC/E5AV5FsTk6MVVQmHohRsDIpmdnB+laZDD8ffO9YlfIrjILJAsPfQA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1622066583; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UTohWqh3CSUGUskeJH4858GrTk9b2+xV1h3FHXzjaSU=; b=lM0paLMzfM2uJwyiCU7lUlADVqFr7WzxGxoDcbVscPRdeGvlJ5AeIp/xWsGoSEzAIbpUYf BI4Dj9Xu1qZ/k8Cw== To: Andy Lutomirski , syzbot , bp@alien8.de, bp@suse.de, dave.hansen@linux.intel.com, fenghua.yu@intel.com, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, syzkaller-bugs@googlegroups.com, tony.luck@intel.com, x86@kernel.org, yu-cheng.yu@intel.com Subject: Re: [syzbot] WARNING in ex_handler_fprestore In-Reply-To: References: <0000000000004c453905c30f8334@google.com> Date: Thu, 27 May 2021 00:03:03 +0200 Message-ID: <87sg29886g.ffs@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 25 2021 at 17:33, Andy Lutomirski wrote: > On 5/24/21 1:51 AM, syzbot wrote: > I entirely believe that this bug is real and that syzbot bisected it > correctly, but I'm puzzled by the reproducer. It says: The bug is real and the bisection is correct. > ptrace$setregs(0xd, r0, 0x0, &(0x7f0000000080)) > > I would really, really expect this to result from PTRACE_SETREGSET or > PTRACE_SETFPREGS, but this is PTRACE_SETREGS. > > Am I missing something really obvious here? That ptrace muck is a red herring and has nothing to do with it. I decoded it fully by now and will send out coherent info (and hopefully a patch) tomorrow with brain awake. Time for bed here... Thanks, tglx