From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f80.google.com (mail-ot1-f80.google.com [209.85.210.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 742851A6809 for ; Tue, 4 Aug 2026 02:50:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785811833; cv=none; b=suo8IsrdvyVezHwsNr4xBNARuuI9ptU5T0PNZBAheorNN9k3enKRVVcMX5VId3Hd0XSkdFyHzWFqkyLgHUSzR5Aq3FJWNRePG/+Csehc6jEmJe/LudNe2+lq2aMwkMVzGOdmCDoPAmrCPRQ/br9W7e6PANnQSchzFs6bariUhK8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785811833; c=relaxed/simple; bh=X06aGt5TcD0ybUe4qxjs1/MvCceDrQgf7Pwby/2x9lU=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=JtdfpleE13393LouCBQbsNMg06amOum/COJZj+l6+BRV9/iInQlDjk6iAA8KoDn4obPxNJh3oci/A3D3k6vPB+vC0f/mqJbPAXFvR/yLcE9I3W4Tn/oOBfxB1P6+RWGRozncbZyyuyTwq/fnlHGVy/AkzcP6rbVgGw3fKeIb0Yo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.80 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f80.google.com with SMTP id 46e09a7af769-7ee1e335245so3056293a34.1 for ; Mon, 03 Aug 2026 19:50:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785811831; x=1786416631; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=u4iu+m/OXgvK2cVLedf453MP76zfqaed/KskxWW5eNw=; b=kpQpAIpXvx7ATPS10MRhECuF+BcNaQciUXp0O6VSWlag4HcuIB+jnHX51b0WvxE5cf jcFMMYr+BVKZFojiT3ih6ir7mmZNdjeyRRZmt3Yl846CBdMlUbBzRpCl8QrpodVLWUZp 97iciWOr3Ja/xWdqhW5ROZwnQ/UYlc2I69A12N8y2alg7ujhlFn0U3SdixqiaYd1ljGO SDPJXIBxX4j4dlH3c+Ygwzbr84ryG9MQylxeH/eIwysbW6fTJBZ0hFRZbg45WSDlK2kr YMN7aXX7iJ6O7T5PjBMUMKeAH07h5Fzq0pprDDUI2oH6cjxQOTQsxghlh7ye4xAC7KCs xfsQ== X-Gm-Message-State: AOJu0Yxm1bIdODONMytz6yOqHDwOR/3vQx6+qbiu/XFcmmm+94VMMMg3 JeBsuyLSVDL2e2My5hZ174oVrNm+18M7C12PPLsbLcN5zWjNlQT3ZrQyU4bk33NinFqlnsUOxk5 9ulrywtGdDaFhSnMwpMcEXtfAxXMNmb6e8oA5jSrNbK0k6JMXUfSPwmgD/rIq/Q== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:c1e8:b0:497:d371:21c8 with SMTP id 5614622812f47-4af5e2cd936mr19260946b6e.19.1785811831365; Mon, 03 Aug 2026 19:50:31 -0700 (PDT) Date: Mon, 03 Aug 2026 19:50:31 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a715377.d35e88fd.de8b.000a.GAE@google.com> Subject: [syzbot] [trace?] KCSAN: data-race in ring_buffer_unlock_commit / ring_buffer_unlock_commit From: syzbot To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, rostedt@goodmis.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 848acc8ffe1b Merge tag 'fsverity-for-linus' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13731649580000 kernel config: https://syzkaller.appspot.com/x/.config?x=84b3039e8461eef5 dashboard link: https://syzkaller.appspot.com/bug?extid=0168fe25f9e5d46bd5fe compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d1a0ae21bd78/disk-848acc8f.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9be505d18eb6/vmlinux-848acc8f.xz kernel image: https://storage.googleapis.com/syzbot-assets/8ab6a3838bc0/bzImage-848acc8f.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0168fe25f9e5d46bd5fe@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in ring_buffer_unlock_commit / ring_buffer_unlock_commit write to 0xffff888100074cb4 of 1 bytes by task 8271 on cpu 1: rb_wakeups kernel/trace/ring_buffer.c:4295 [inline] ring_buffer_unlock_commit+0x6a/0x440 kernel/trace/ring_buffer.c:4495 __buffer_unlock_commit kernel/trace/trace.h:1697 [inline] trace_buffer_unlock_commit_regs+0x43/0x310 kernel/trace/trace.c:2049 trace_event_buffer_commit+0x149/0x590 kernel/trace/trace.c:2024 do_trace_event_raw_event_hrtimer_setup include/trace/events/timer.h:193 [inline] trace_event_raw_event_hrtimer_setup+0xc9/0x170 include/trace/events/timer.h:193 __do_trace_hrtimer_setup include/trace/events/timer.h:193 [inline] trace_hrtimer_setup include/trace/events/timer.h:193 [inline] debug_setup_on_stack kernel/time/hrtimer.c:523 [inline] hrtimer_setup_sleeper_on_stack+0xd1/0xf0 kernel/time/hrtimer.c:2366 schedule_hrtimeout_range_clock+0x71/0x1a0 kernel/time/sleep_timeout.c:211 schedule_hrtimeout_range+0x28/0x40 kernel/time/sleep_timeout.c:263 poll_schedule_timeout fs/select.c:241 [inline] do_select+0xed3/0xfa0 fs/select.c:603 core_sys_select+0x453/0x730 fs/select.c:677 do_pselect fs/select.c:770 [inline] __do_sys_pselect6 fs/select.c:809 [inline] __se_sys_pselect6+0x23f/0x2a0 fs/select.c:800 __x64_sys_pselect6+0x78/0x90 fs/select.c:800 x64_sys_call+0x8d5/0x3020 arch/x86/include/generated/asm/syscalls_64.h:271 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff888100074cb4 of 1 bytes by task 8264 on cpu 0: rb_wakeups kernel/trace/ring_buffer.c:4294 [inline] ring_buffer_unlock_commit+0x54/0x440 kernel/trace/ring_buffer.c:4495 __buffer_unlock_commit kernel/trace/trace.h:1697 [inline] trace_buffer_unlock_commit_regs+0x43/0x310 kernel/trace/trace.c:2049 trace_event_buffer_commit+0x149/0x590 kernel/trace/trace.c:2024 do_trace_event_raw_event_sock_msg_length include/trace/events/sock.h:267 [inline] trace_event_raw_event_sock_msg_length+0x10f/0x1c0 include/trace/events/sock.h:267 __do_trace_sock_recv_length include/trace/events/sock.h:304 [inline] trace_sock_recv_length include/trace/events/sock.h:304 [inline] call_trace_sock_recv_length+0xa2/0xc0 net/socket.c:1120 sock_recvmsg_nosec+0xdf/0xf0 net/socket.c:1131 ____sys_recvmsg+0x26f/0x280 net/socket.c:2902 ___sys_recvmsg+0x11f/0x3a0 net/socket.c:2946 do_recvmmsg+0x1e5/0x560 net/socket.c:3041 __sys_recvmmsg net/socket.c:3115 [inline] __do_sys_recvmmsg net/socket.c:3138 [inline] __se_sys_recvmmsg net/socket.c:3131 [inline] __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3131 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x01 -> 0x00 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 8264 Comm: syz.5.1654 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup