From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out203-205-221-202.mail.qq.com (out203-205-221-202.mail.qq.com [203.205.221.202]) (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 EFFDC4A06; Tue, 10 Jun 2025 01:07:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.205.221.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749517649; cv=none; b=LMPCMwRoGV8ugaIzRVYifxxHXifoO7GhblOqsNPKN94bePNipmDy8sPA9adMA489G0YQeXjlalJI3qYhn6LIA4x03E5XbeRSgcQFM8wURTPK1D/BBoSN2Utn4AuvPMjui4EUSpuY1Y91Vz7oTfT+YxN4z00MPpT6nsNMSazNDkk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749517649; c=relaxed/simple; bh=S4W2n44VZNjNQzVeKTirqpN4tB3suesRR4Frf/aHbwU=; h=Message-ID:From:To:Cc:Subject:Date:In-Reply-To:References: MIME-Version; b=OQt6KAjZ7is6r/uN0wYXYapx5f7b3DDmGO1JlDSH8wbxi+rgLcuB8VDRr3rBXyJ+bIZBMvziQ2F9xwof5p+iAamB+J5sjRMq1HozMGYjhdQA7Zve/eD5pj0MdSQjdv12yGfe+34pRe0ho4//2AWmOIxZ5Neb9MRsJbaEDauPl3c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com; spf=pass smtp.mailfrom=qq.com; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b=sz3pBGEP; arc=none smtp.client-ip=203.205.221.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qq.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b="sz3pBGEP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qq.com; s=s201512; t=1749517633; bh=c9MRFQDxeQxfty8SkiULH3HLoA0rW9xJB0zfq7hF8Wc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=sz3pBGEPU4oIuxJa4plFurdXvNsNOIiCgEnX3lbvuziHqwu9i1n5LJPqLeVkjHaUg 6t4cid0yz0A90ArbuUhczfb4xTR+KFGirfzUQukW8YuLc0AsLGjbw5NAOwcFrbzp5X DUXBKDj16hc1BSZIsHUX1XXCtmt3LXOS3XePFy9E= Received: from pek-lxu-l1.corp.ad.wrs.com ([111.198.228.63]) by newxmesmtplogicsvrszc16-0.qq.com (NewEsmtp) with SMTP id 409EE7E; Tue, 10 Jun 2025 09:01:00 +0800 X-QQ-mid: xmsmtpt1749517260tcilbvdw6 Message-ID: X-QQ-XMAILINFO: Mdc3TkmnJyI/UR/645hUHJDSdJ3g3z4WYkjn15lWkZAL0/Yn9qDE4a4e3cO8LS hdQNMHs1F9MxHIYiothFiHdtaL4Bi60DAJ7dJXI4+xs+vHlFS0thIUpXKMIg/Q6dIslCUL4elK+D DJFobT+aSB4EX3GV/TnBwkx1tiJe83vGPIRi+lmWblfIBgBuSUuQDQFtHpt81AI5heq3w5WhJhCN nQwcB2Z86Iivw/DJlNkKkNv1bi/Jw/ypXd/UciHCDIkYkkkB1Zab1ZuOxr2mOhau3s3DyzcmhYO+ 9EO2exKjnxKWsFMHq59Qokq4+IcmMlQBeF7RpFiBpns5X47a34doQQbpdEZ36ZeeVO9NrZNysTzY X35OcpWQ/LMNi4b/sNE5Q/lfAlWgUoqtHLuta5cP10fcVAJ/7KDkVEXpke5LV/jQKizi7uO66xdA hmqF1E7zoA1EXUrqOgGlEdV+rmrwSX6f/WYPs+2sCZjEdMBplJKp1SWBZqtp/SmM+ip9TM4fCLf7 GoUkQ5QYU6zGTwigxe/XM9FCi1Yo62gJf2wXIyVRHa62uX3SXkiDFfdRVl/NkC8v4Af6JGMbSQnd i++rUrtNppksoYwuyYIE2H/x/0ilzJIA20ezA6Klj9YctDcoHK1ngY8RWuAwtvF9S1GFbuo0guVq YjSrU7UTuDd4xIH2fskghadlfc351Szi6DfWzGQC9dW+KdVYaKDPVer5adpx/8LTXKiF1GfHICmL JchxGr1W7WEVa/3MMJdz99lq6UaJkchCFf/49Q5W07b6SV+C7riLi5QKj8rOMYdoDxEWgPnhdqTW oglhiMWz3Exs8dQyivPrZXz5v1RwdEQ3xIL3Z/8Imft+FLa19o57A4z179/PaCicy3Wra5ZDql6J O4vQpNvw2rNI8YfBSlfv6/Zb9M4hwr8R6G+FJCA+b858W8crfZSjDfImMvMWCSJKBKXti7GDkl X-QQ-XMRINFO: OWPUhxQsoeAVDbp3OJHYyFg= From: Edward Adam Davis To: syzbot+eb6f218811a9d721fd53@syzkaller.appspotmail.com Cc: andrew+netdev@lunn.ch, andrew@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, richardcochran@gmail.com, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [net?] possible deadlock in ptp_clock_unregister Date: Tue, 10 Jun 2025 09:01:01 +0800 X-OQ-MSGID: <20250610010100.1154477-2-eadavis@qq.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <68478027.050a0220.33aa0e.02e7.GAE@google.com> References: <68478027.050a0220.33aa0e.02e7.GAE@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > syz-executor421/5891 is trying to acquire lock: > ffff888079fcc868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: ptp_vclock_in_use drivers/ptp/ptp_private.h:103 [inline] > ffff888079fcc868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: ptp_clock_unregister+0x21/0x250 drivers/ptp/ptp_clock.c:415 > > but task is already holding lock: > ffff8880300cc868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: n_vclocks_store+0xf1/0x6d0 drivers/ptp/ptp_sysfs.c:215 They are not the same lock. > > other info that might help us debug this: > Possible unsafe locking scenario: > > CPU0 > ---- > lock(&ptp->n_vclocks_mux); > lock(&ptp->n_vclocks_mux); > > *** DEADLOCK ***