From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail115-63.sinamail.sina.com.cn (mail115-63.sinamail.sina.com.cn [218.30.115.63]) (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 C0179199EBB for ; Tue, 22 Oct 2024 11:42:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=218.30.115.63 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729597369; cv=none; b=Al9vw50DAfp94BsoLvIZM6PfatI80j51kjJvq24IDIFDZ3QKOUwQX8UEqkY+cqmFKsGjxVHDt0uUe/KDKPlwwjWQczpr2KwbZwiVtuQsl+F7/sMh0arcAlR5BFMdBpk1VEL5OuPRfF4bjFGudESnE30CPQNwW7R76FfI/iNA7ew= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729597369; c=relaxed/simple; bh=fiLvjqiCky4scaYOA6J4GlmocifpCmL/hB2+SAwnFfo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fSEgYBNtUL1raJH4MSg0rf/rz6Pye/dDSNVMvSx2Pmp2bEZrQS+BVbLVVw8MzlrpdtAz01k14wtadyq/rcNmfcd0jaxSp0/RPERvs2dgcqmVCWEitOwT76CphB5+oRaP09J2pJNX7+A+aperHR0Zcu5IiAIDgqHCyBgpsHhbpzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; arc=none smtp.client-ip=218.30.115.63 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([113.118.70.205]) by sina.com (10.185.250.22) with ESMTP id 67178FA900007C24; Tue, 22 Oct 2024 19:42:37 +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: 1711477602652 X-SMAIL-UIID: E3EC872BFAA84B73A8990DED069A75CD-20241022-194237-1 From: Hillf Danton To: Oliver Neukum Cc: syzbot , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, stern@rowland.harvard.edu, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [usb?] INFO: task hung in usb_port_suspend Date: Tue, 22 Oct 2024 19:42:25 +0800 Message-Id: <20241022114225.2314-1-hdanton@sina.com> In-Reply-To: <0abd3cbd-0e8a-43b2-8cb0-6556297aa7c9@suse.com> References: <67153205.050a0220.1e4b4d.0048.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 On Mon, 21 Oct 2024 10:04:52 +0200 Oliver Neukum > On 20.10.24 18:38, syzbot wrote: > > > INFO: task kworker/0:0:8 blocked for more than 143 seconds. > > Not tainted 6.12.0-rc3-syzkaller-00051-g07b887f8236e #0 > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > > task:kworker/0:0 state:D stack:24544 pid:8 tgid:8 ppid:2 flags:0x00004000 > > Workqueue: pm pm_runtime_work > > Call Trace: > > > > context_switch kernel/sched/core.c:5322 [inline] > > __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 > > __schedule_loop kernel/sched/core.c:6759 [inline] > > schedule+0xe7/0x350 kernel/sched/core.c:6774 > > And this sleeps forever. This must not happen. > > usb_kill_urb.part.0+0x1ca/0x250 drivers/usb/core/urb.c:713 > > usb_kill_urb+0x83/0xa0 drivers/usb/core/urb.c:702 > > We are changing our mind, presumably due to a timeout > > usb_start_wait_urb+0x255/0x4c0 drivers/usb/core/message.c:65 > > We are sending a control message, presumably to enable > remote wakeup > > usb_internal_control_msg drivers/usb/core/message.c:103 [inline] > > usb_control_msg+0x327/0x4b0 drivers/usb/core/message.c:154 > > usb_enable_remote_wakeup drivers/usb/core/hub.c:3365 [inline] > > usb_port_suspend+0x339/0xf10 drivers/usb/core/hub.c:3472 > > Suspending ... > > usb_generic_driver_suspend+0xeb/0x1d0 drivers/usb/core/generic.c:302 > > usb_suspend_device drivers/usb/core/driver.c:1272 [inline] > > usb_suspend_both+0x66d/0x9c0 drivers/usb/core/driver.c:1443 > > usb_runtime_suspend+0x49/0x180 drivers/usb/core/driver.c:1968 > > This very much looks like the HC driver used to run these tests > can hand in unlink. If that happens there is nothing usbcore > or a driver can do. > A one-line change could survive the reproducer [1]. [1] https://yhbt.net/lore/lkml/67178c80.050a0220.1e4b4d.0075.GAE@google.com/