From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f78.google.com (mail-oo1-f78.google.com [209.85.161.78]) (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 C7D0F314B6E for ; Fri, 6 Feb 2026 07:34:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770363275; cv=none; b=ZOlGnI0oxTWQ//rvF/QZbuQcnnKjzU/L4Z3O8pMZdmR1M58FbnIplKewPMGux+TstVUR7XLhilhnewbn8gmJGtRFSC24GcvWNlOzi47s86xrHeWPUBh665+Uajv06iqUXoWGEd4n/nI1TWiaCwiSWMhUMGLAM8/vw+1AWgCzg98= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770363275; c=relaxed/simple; bh=Kp4498QLNmfK2CENtyJGX4EnK7PU2z/HA2kg+ZfYHTY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=MnFE2e0uS5Eg828zWiV0LA3zMO17QW20qMGXbbFTKBfIYvb4b2kBDUVqEFaS0kZYKL1dBefF3YKMkGVgqW0OIQj2+Xhpwvt8RnIkYWntHPLhoZojq/h7sjJDajFOxyoZw0iKL7MAI7fdTrJyCMls2x3zDlf/UPL+Nrxl6afMT8Y= 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=209.85.161.78 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-oo1-f78.google.com with SMTP id 006d021491bc7-663006e4c3cso6445409eaf.2 for ; Thu, 05 Feb 2026 23:34:34 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770363274; x=1770968074; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=R3kTvYB9PubGKsbSG4SV7nCcfBTsVFg92MFXjJGgdxA=; b=J3Mv2NbS41GsgBpb1vd1L66aFUOEV97l62IgWCR8LF7pp7P53E2We+zWUNiWXgPln4 zBQnVlQ4ZGFZMaPm5n9+EwVhGyjTVhyRtpCYE2ONDKZp7No7BCablh45ctyJekvEWcLw wPIClVANcapV44Cc87R90cnPLruXgCtNs8Fo4ZhZ9c2eibgUFTNJ7FlAzyISyujVsRgy DFntBOj5nW/v+s9fm6utQAWlLNZcF+gJI304O6Ep48Kh7d0rUPUsi93UsCjhwv9Pj4M4 j2Gq3DMxWYmccO0r1LSqON1RFj/9HZ3Dt7JMXnsmFtrbqQJqmc1Xyoc1sRH+1qXvd8UO jWsw== X-Forwarded-Encrypted: i=1; AJvYcCXC+F3XuigCkrlg9y3oNMaIbY0iQbIO0+xAEt+zOOzBrfZ2pKjcI1UFdc9mItayYRJR02E6/pBU+rN5EGqQNAje@vger.kernel.org X-Gm-Message-State: AOJu0YzOA+traRu5RnRiXih02NE0WhXeDZdaLob10m8gAVAgFDs1JZZ9 WeONbOC1UOeZSYqJEFm0+xRGytGMtjw9S1Wa974NbOijwSJL3+E3cbs5DynifPByMF9xGgbowoz LxewhZtF+9dB/3y9qIFDWayRWMTjwbkJwjn9f2BqHvwibIlNiIplrwRuzGEE= Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:4dc8:b0:659:9a49:904d with SMTP id 006d021491bc7-66d0a37b727mr970006eaf.24.1770363273798; Thu, 05 Feb 2026 23:34:33 -0800 (PST) Date: Thu, 05 Feb 2026 23:34:33 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69859989.a00a0220.34fa92.0026.GAE@google.com> Subject: [syzbot] [perf?] KCSAN: data-race in __perf_event_read_value / perf_event_set_state (6) From: syzbot To: acme@kernel.org, adrian.hunter@intel.com, alexander.shishkin@linux.intel.com, irogers@google.com, james.clark@linaro.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mark.rutland@arm.com, mingo@redhat.com, namhyung@kernel.org, peterz@infradead.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 5dbeeb268b63 Merge tag 'driver-core-6.19-rc7' of git://git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=169a105a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6c9e86480ac654d3 dashboard link: https://syzkaller.appspot.com/bug?extid=6d5529efa784dcc0b926 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8a4a5a3502b5/disk-5dbeeb26.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/65e86e2ad6af/vmlinux-5dbeeb26.xz kernel image: https://storage.googleapis.com/syzbot-assets/050ae083081a/bzImage-5dbeeb26.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6d5529efa784dcc0b926@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in __perf_event_read_value / perf_event_set_state write to 0xffff8881311a8538 of 8 bytes by task 13031 on cpu 1: __perf_update_times kernel/events/core.c:-1 [inline] perf_event_update_time kernel/events/core.c:735 [inline] perf_event_set_state+0x1c4/0x440 kernel/events/core.c:754 event_sched_out+0x2d4/0x4d0 kernel/events/core.c:2391 group_sched_out kernel/events/core.c:2415 [inline] __pmu_ctx_sched_out+0x3e7/0x530 kernel/events/core.c:3458 ctx_sched_out+0x273/0x2d0 kernel/events/core.c:3539 task_ctx_sched_out+0x4d/0x70 kernel/events/core.c:2859 perf_event_context_sched_out kernel/events/core.c:3746 [inline] __perf_event_task_sched_out+0x2df/0x3c0 kernel/events/core.c:3846 perf_event_task_sched_out include/linux/perf_event.h:1654 [inline] prepare_task_switch kernel/sched/core.c:5049 [inline] context_switch kernel/sched/core.c:5205 [inline] __schedule+0xbaa/0xc90 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x5e/0xd0 kernel/sched/core.c:6964 futex_do_wait kernel/futex/waitwake.c:358 [inline] __futex_wait+0x121/0x260 kernel/futex/waitwake.c:687 futex_wait+0x9c/0x1d0 kernel/futex/waitwake.c:715 do_futex+0x2bf/0x380 kernel/futex/syscalls.c:130 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex+0x2f6/0x370 kernel/futex/syscalls.c:188 __x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:188 x64_sys_call+0x2bc2/0x3000 arch/x86/include/generated/asm/syscalls_64.h:203 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff8881311a8538 of 8 bytes by task 13182 on cpu 0: __perf_event_read_value+0xb6/0x1d0 kernel/events/core.c:5894 perf_read_one kernel/events/core.c:6049 [inline] __perf_read kernel/events/core.c:6102 [inline] perf_read+0x171/0x4f0 kernel/events/core.c:6119 loop_rw_iter+0x2c6/0x3f0 include/linux/uio.h:-1 io_iter_do_read io_uring/rw.c:836 [inline] __io_read+0xbf6/0xc50 io_uring/rw.c:950 io_read+0x4a/0x190 io_uring/rw.c:1030 __io_issue_sqe+0xfd/0x2d0 io_uring/io_uring.c:1793 io_issue_sqe+0x56/0xa70 io_uring/io_uring.c:1816 io_wq_submit_work+0x3f7/0x5f0 io_uring/io_uring.c:1928 io_worker_handle_work+0x41e/0x950 io_uring/io-wq.c:650 io_wq_worker+0x22d/0x860 io_uring/io-wq.c:704 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 value changed: 0x000000004a891b66 -> 0x000000004a89847d Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 13182 Comm: iou-wrk-13031 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 ================================================================== --- This report is generated by a bot. 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