From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from r3-22.sinamail.sina.com.cn (r3-22.sinamail.sina.com.cn [202.108.3.22]) (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 7B25B2CCB9 for ; Tue, 28 Apr 2026 22:02:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.22 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777413738; cv=none; b=EVi0GiuSIVOED82mRpzPUoo2e+f0+F6sEuoHTcXLGqdgvGTwFGDP/l7ktc6UTQQBQZCf+/xi+CB8L30L7iZvOIfVounsZMMXgEEO8uf9aiykzD5Zj8jONgrxZ9CxGHt00qJ2mZkyrh3+ue/GeWX1tFrcXkCgz67iiWA2qP6dLJg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777413738; c=relaxed/simple; bh=HwzAq/TfhPfE4pGeLT3qzWSfQIKs2aGsnLgERhJB8fg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=p3d7W43OtNObEKmMY3o0YN7KfLjeblDOi8cPTe+jMi2Y74Kfv2rEUycVooD9VOVygPFVbqlx5rP2awYBMdT+5RROFgCEH6kcUSkN3Qg4ljOL/6uKko8pNraHAdFHum+tcdoRzjdrh9DgyXKwoLMLyfZU99oXb52Y0gdTbiiqc4I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=tkBfDqN0; arc=none smtp.client-ip=202.108.3.22 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="tkBfDqN0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1777413734; bh=28JJVqXVOnUopmUS/Abh5dnCrC8/ya9rIbvodwPxJd8=; h=From:Subject:Date:Message-ID; b=tkBfDqN041azkKu8x3ueQy6grAC1j2LD/hLN0r7andKkg1vkRAvUwFvUiFaPRT+DX HXGZBR9yiO4Vbgrgfjj8AcxhL+3AC7vxc+zKFV0BApGTMGjJNPfgNKTMe6H8HaT0j1 AeWSe20PD67zFCHh2iTlGE8x/Cj5MOBuxGS1Y7Gc= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.62.144]) by sina.com (10.54.253.33) with ESMTP id 69F12E580000226A; Tue, 29 Apr 2026 06:02:02 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 3023656685003 X-SMAIL-UIID: 5C73B99B28A947CD9A607C438F03D9BB-20260429-060202-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [kernel?] general protection fault in remove_waiter Date: Wed, 29 Apr 2026 06:01:49 +0800 Message-ID: <20260428220150.2264-1-hdanton@sina.com> In-Reply-To: <69f114ac.050a0220.ac8b.0003.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Tue, 28 Apr 2026 13:12:28 -0700 [thread overview] > Hello, > > syzbot found the following issue on: > > HEAD commit: 897d54018cc9 Merge tag 'fbdev-for-7.1-rc1-2' of git://git... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=172c32ce580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=59da38148f3a3d24 > dashboard link: https://syzkaller.appspot.com/bug?extid=78147abe6c524f183ee9 > compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10c7f273980000 #syz test --- x/kernel/locking/rtmutex.c +++ y/kernel/locking/rtmutex.c @@ -1558,6 +1558,8 @@ static void __sched remove_waiter(struct lockdep_assert_held(&lock->wait_lock); + if (!waiter_task) + return; scoped_guard(raw_spinlock, &waiter_task->pi_lock) { rt_mutex_dequeue(lock, waiter); waiter_task->pi_blocked_on = NULL; --