From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (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 E84303E493 for ; Wed, 17 Apr 2024 14:50:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713365445; cv=none; b=ZWD472w2OT1BhiLw7co7TIcrkh8LSgNNZizZ6jAmzQt63pn3FOaSttHFV02lovBmayacsF1JXD2YOT7bW7xljCZzrfdQFxYe1vaegZ59rDHul8wToAgBtAXRyr0RulfLt2XAVxOtZ0UICHYiqU3ku2nOSn7xlH7zWH4DweDqyDA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713365445; c=relaxed/simple; bh=3xQjIKuzza23PA8iMmF/ZaihPTYzQa4id/sKfn3o+Hk=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=rkNpvOu7rVWdGYPEYKCOYKhgIMAeMWZ0EkdMCM+zWgfBNDRs62B1RrC/e3VNh2PnjZWCkXYX/o70OpS+zUXnW+Ty6vM8gYfW6G7XjzAuV1P3TAMyYKSgAGZvcsJVMKkCKuNA+th1/iiO2G0ocuMaRXOv3glYrvA4HcfAagikYdY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=O6oY5ILm; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="O6oY5ILm" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-1e3c89f3d32so221185ad.0 for ; Wed, 17 Apr 2024 07:50:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1713365443; x=1713970243; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=rxj80oam7Il+91X8ofj6LPJmgE1D5E+WVqYl1M/aFRo=; b=O6oY5ILmgiqKuEE6iElybv2Ub9WHKOEhLmXEmwUOaX5zfBnjiDrRYHLiAKDNMoz6co e25zKESy77M6a/uxtxaBGAyTnJ7suprR/puZL3FScnbwnYebEnh9zH7OmK5Mp3P/zf48 3X2U/LxOdgyacu26zOqARLxhWZQBVShE5i1omT/noNt2EHV0ufnLw3Td6NLy1zsDejPz HT23jtuo63UUulEqbt2Ab6qeXeMWbcXhh+fl2X2iWFWZfvpQGSVgIG6gg3LdLG5zaPQR 4QzDTWWRhe/rh9xFGQyV2f9onxwO7TL2ucjco4R/fUOl+56FyC7mvxupB4o1WARt43z9 CRsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713365443; x=1713970243; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=rxj80oam7Il+91X8ofj6LPJmgE1D5E+WVqYl1M/aFRo=; b=Sqva5ePrynySu8OfgP5f8Ofag3A3PzUERCfCVxscoQkrtzO9t6bCkEOatNhIlROeQZ 6hYxjj3DbF4K9zBQlENMb4hfoVIuzZ+dKvQhx9sB3Zvcnz+o5ewzeGFWElNqBk5RnuIU h4gXOEozXWD2p854oga/6NOP7Om3G67gcpkxHnwHsri7fscWqJWS/kBwBqSXZ5yjR/3/ eC8ipf7uQFQP+wFEB14xqz6BdENhN7ugbPCacPHvbio7FgiR1zq93irX++cNRdOB1yWF 9XmsSD9L8uiAKX43sBiZbLR41YHJKdljE14glW9tu77P7k5rqgiasATkfM8yz4udiIFK WoBQ== X-Gm-Message-State: AOJu0YxwN8kBKU5pkpt+KngBC6AbkMaAkRy8kl29MNl4X8EpYBzp9dge 8wW0uVGYLsEJs6KZFj3zUly5ogMq0t9hrXcd03crN69Lz3fxBwm6TSQpZF0cJes9S5etlwCTEQn 9ibZyPxaE8/m0amTEIKGCamOMQjJDwMizzuQzIA7xx2GfvyNoW+89aCw= X-Google-Smtp-Source: AGHT+IGHxKwu98YvospB91+YQLFfAJMnppT/6GTQ5TqAb0PWkruGOWlmlwOEwP83YxDHUDlUQUZTDwY8gkvcPDj3jKI= X-Received: by 2002:a17:903:42c6:b0:1e3:d23a:2d5e with SMTP id jy6-20020a17090342c600b001e3d23a2d5emr196816plb.21.1713365442847; Wed, 17 Apr 2024 07:50:42 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: In-Reply-To: From: Ian Rogers Date: Wed, 17 Apr 2024 07:50:27 -0700 Message-ID: Subject: Re: [Linux kernel bug] WARNING in free_event To: Sam Sun Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, adrian.hunter@intel.com, jolsa@kernel.org, alexander.shishkin@linux.intel.com, mark.rutland@arm.com, namhyung@kernel.org, acme@kernel.org, mingo@redhat.com, peterz@infradead.org, syzkaller-bugs@googlegroups.com, xrivendell7@gmail.com, zqq0103.hey@gmail.com, Frederic Weisbecker , haifeng.xu@shopee.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Apr 17, 2024 at 6:38=E2=80=AFAM Sam Sun w= rote: > > Dear developers and maintainers, > > We encountered a kernel warning in the function free_event() while > using our modified syzkaller. It was tested on the latest upstream > linux(6.9-rc4). C repro and kernel config are attached to this email. > Kernel dump log is listed below. > ``` Thank you for the report, unfortunately there have also been similar reports and some possibly related fixes posted: https://lore.kernel.org/linux-perf-users/CAP-5=3DfUa+-Tj2b_hxk96Qg5=3DQu7jY= HgHREbsmBa2ZmuF-X9QaA@mail.gmail.com/ https://lore.kernel.org/lkml/20240329235812.18917-1-frederic@kernel.org/ https://lore.kernel.org/lkml/20240410035506.599192-1-haifeng.xu@shopee.com/ Thanks, Ian > ------------[ cut here ]------------ > unexpected event refcount: 2; ptr=3Dffff88801931e0c0 > WARNING: CPU: 0 PID: 8082 at kernel/events/core.c:5254 > free_event+0xa3/0xc0 kernel/events/core.c:5254 > Modules linked in: > CPU: 0 PID: 8082 Comm: syz-executor381 Not tainted 6.7.0-rc7 #1 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > 1.13.0-1ubuntu1.1 04/01/2014 > RIP: 0010:free_event+0xa3/0xc0 kernel/events/core.c:5254 > Code: b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 25 48 8b > b5 38 02 00 00 48 89 ea 48 c7 c7 c0 38 b7 8a e8 6e 30 9e ff 90 <0f> 0b > 90 90 5d 41 5c 41 5d e9 bf 45 d7 ff 4c 89 ef e8 d7 e9 2b 00 > RSP: 0018:ffffc9000176f9e8 EFLAGS: 00010282 > RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff814c00fa > RDX: ffff888063d919c0 RSI: ffffffff814c0107 RDI: 0000000000000001 > RBP: ffff88801931e0c0 R08: 0000000000000001 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000002 > R13: ffff88801931e2f8 R14: ffff88801931e3a0 R15: ffff88801931e0c0 > FS: 0000000000000000(0000) GS:ffff888044200000(0000) knlGS:0000000000000= 000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000008 CR3: 000000000cd78000 CR4: 0000000000750ef0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > > perf_event_release_kernel+0x5d4/0x8f0 kernel/events/core.c:5421 > perf_release+0x37/0x50 kernel/events/core.c:5442 > __fput+0x282/0xbb0 fs/file_table.c:394 > task_work_run+0x168/0x260 kernel/task_work.c:180 > exit_task_work include/linux/task_work.h:38 [inline] > do_exit+0xaf0/0x2a40 kernel/exit.c:869 > do_group_exit+0xd4/0x2a0 kernel/exit.c:1018 > get_signal+0x243c/0x2630 kernel/signal.c:2904 > arch_do_signal_or_restart+0x81/0x7d0 arch/x86/kernel/signal.c:309 > exit_to_user_mode_loop kernel/entry/common.c:168 [inline] > exit_to_user_mode_prepare+0x121/0x240 kernel/entry/common.c:204 > __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] > syscall_exit_to_user_mode+0x1e/0x60 kernel/entry/common.c:296 > ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 > > ``` > If you have any questions, please contact us. > Reported by: Yue Sun > Reported by: xingwei lee > > Best Regards, > Yue