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 F3EE779CD for ; Sat, 30 Aug 2025 01:00:21 +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=1756515627; cv=none; b=D7le36mrz3ZSjtf2JLDlsIiQAnzBg3BAgpJOQfjwV4SmUsJvjhJmu58v6UcfPNqnqB3hDuSeqKOlZWRm08w558gPRD40mMKzMGJehFN7iYya709pdycloTAagy3ibFh7hjuGCghuYlMhEbAjZqXpu2yTsXUtSJ0f1YgjMb4A/Yw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756515627; c=relaxed/simple; bh=FCCUW6Tp1vpxSSxhq25s58vyqtb18y8OiG2eGRPV0dM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eTjn2YZqjFTXUkfMuC1a0lk6/swDfLODUL0/0ErZdDtaLWCT4UZ2GcdZh8z5Jf2KFNFR0DGTLrpiWooZwBUSshENLs5EOKXpxObe101M8Dceyh3S/oNAQHso15hhQxzQiR6fpUSevg8f+JOK4jo9n6bvUHby8OJOnCK6VxzZ8iE= 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=q2y8t61/; 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="q2y8t61/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1756515622; bh=wLhZjOLKWoS7OMBm2ACxQn1eRHsFKZD8VEXouXR/S38=; h=From:Subject:Date:Message-ID; b=q2y8t61/BNoE9ung2E1rQrTwuuFeX6mpq27FALKmzFKVcHkQ7NLq7ImeZIy7V3Mc1 0LTEfNO3SxP7YT6LUu/D2cGD8CsZg6Q9jQlH05K1jgSeIFQr7AxVD8XfY+0SsyplRy VwUG+tM8QjmAAQuXN8sN6anmxk2g8w5gM9bmFUJs= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.58.236]) by sina.com (10.54.253.33) with ESMTP id 68B24CF8000040EE; Sat, 30 Aug 2025 08:59:37 +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: 9298016685263 X-SMAIL-UIID: 4C644413EA294755AFF258DA2B6EC949-20250830-085937-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [net?] WARNING in est_timer Date: Sat, 30 Aug 2025 08:59:25 +0800 Message-ID: <20250830005927.6096-1-hdanton@sina.com> In-Reply-To: <68b1a996.a70a0220.f8cc2.00ee.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: Fri, 29 Aug 2025 06:22:30 -0700 [thread overview] > syzbot has found a reproducer for the following issue on: > > HEAD commit: 07d9df80082b Merge tag 'perf-tools-fixes-for-v6.17-2025-08.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=13d67262580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=e1e1566c7726877e > dashboard link: https://syzkaller.appspot.com/bug?extid=72db9ee39db57c3fecc5 > compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1141c262580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13f69262580000 #syz test --- x/net/core/gen_estimator.c +++ y/net/core/gen_estimator.c @@ -90,10 +90,12 @@ static void est_timer(struct timer_list rate = (b_packets - est->last_packets) << (10 - est->intvl_log); rate = (rate >> est->ewma_log) - (est->avpps >> est->ewma_log); + preempt_disable(); write_seqcount_begin(&est->seq); est->avbps += brate; est->avpps += rate; write_seqcount_end(&est->seq); + preempt_enable(); est->last_bytes = b_bytes; est->last_packets = b_packets; --