From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from r3-25.sinamail.sina.com.cn (r3-25.sinamail.sina.com.cn [202.108.3.25]) (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 88E398F7D for ; Sat, 2 Aug 2025 02:58:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754103537; cv=none; b=MS9SLFYZAb1uKOGPQfre5H8a6dDHFmGltCgO0tZ9oAYKhzmm46cHDbXdqhlAWn4ZALzbNQc5xlMfuVEIcFDsFqKcCbWDJA/y1WFKPicQLl1FJLNVEYqsKALbkuEFMc3NHa8ZWQpKwWs8GM6Aa21L6jNywP4Hi9UfFcoM39QdTik= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754103537; c=relaxed/simple; bh=hQFSNUG7Mlc1PyowN/WACGYbNwCnZJ8ZppesueYXL7Q=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; 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<20250802025832.3683-1-hdanton@sina.com> In-Reply-To: <688cf3e0.a00a0220.26d0e1.0074.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Fri, 01 Aug 2025 10:05:36 -0700 [thread overview] > Hello, > > syzbot found the following issue on: > > HEAD commit: 89748acdf226 Merge tag 'drm-next-2025-08-01' of https://gi.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=164a9cf0580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=caba3b7d5edc3bd1 > dashboard link: https://syzkaller.appspot.com/bug?extid=95069c82577357ff89d8 > compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/7d6418d10fb8/disk-89748acd.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/4608f748b818/vmlinux-89748acd.xz > kernel image: https://storage.googleapis.com/syzbot-assets/92e2adcd74de/bzImage-89748acd.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+95069c82577357ff89d8@syzkaller.appspotmail.com > > BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 > in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 30, name: ksoftirqd/1 > preempt_count: 0, expected: 0 > RCU nest depth: 2, expected: 2 > 7 locks held by ksoftirqd/1/30: > #0: ffffffff8d64a6a0 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0xa1/0x400 kernel/softirq.c:163 > #1: ffff8880b8923d90 ((softirq_ctrl.lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] > #1: ffff8880b8923d90 ((softirq_ctrl.lock)){+.+.}-{3:3}, at: __local_bh_disable_ip+0x264/0x400 kernel/softirq.c:168 > #2: ffffffff8d7a8b00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] > #2: ffffffff8d7a8b00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] > #2: ffffffff8d7a8b00 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] > #2: ffffffff8d7a8b00 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1bb/0x2c0 kernel/locking/spinlock_rt.c:57 > #3: ffffffff8d7a8b00 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0xa1/0x400 kernel/softirq.c:163 > #4: ffff88801989a138 ((wq_completion)events_bh){+...}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] > #4: ffff88801989a138 ((wq_completion)events_bh){+...}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 > #5: ffffc90000a4fa00 ((work_completion)(&bh->bh)){+...}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] > #5: ffffc90000a4fa00 ((work_completion)(&bh->bh)){+...}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 > #6: ffff8880b8928b50 ((lock)#3){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] > #6: ffff8880b8928b50 ((lock)#3){+.+.}-{3:3}, at: kcov_remote_start+0x92/0x460 kernel/kcov.c:865 > irq event stamp: 58091 > hardirqs last enabled at (58090): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] > hardirqs last enabled at (58090): [] _raw_spin_unlock_irqrestore+0x85/0x110 kernel/locking/spinlock.c:194 > hardirqs last disabled at (58091): [] kcov_remote_start_usb_softirq include/linux/kcov.h:88 [inline] > hardirqs last disabled at (58091): [] __usb_hcd_giveback_urb+0x3f5/0x710 drivers/usb/core/hcd.c:1662 > softirqs last enabled at (58074): [] ksoftirqd_run_end kernel/softirq.c:282 [inline] > softirqs last enabled at (58074): [] run_ksoftirqd+0xce/0x210 kernel/softirq.c:969 > softirqs last disabled at (58082): [] smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160 > CPU: 1 UID: 0 PID: 30 Comm: ksoftirqd/1 Tainted: G W 6.16.0-syzkaller-10499-g89748acdf226 #0 PREEMPT_{RT,(full)} When was RT turned on in syzbot tests, and for what? > Tainted: [W]=WARN > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 > Call Trace: > > dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 > __might_resched+0x44b/0x5d0 kernel/sched/core.c:8957 > __rt_spin_lock kernel/locking/spinlock_rt.c:48 [inline] > rt_spin_lock+0xc7/0x2c0 kernel/locking/spinlock_rt.c:57 > spin_lock include/linux/spinlock_rt.h:44 [inline] > kcov_remote_start+0x92/0x460 kernel/kcov.c:865 > kcov_remote_start_usb include/linux/kcov.h:55 [inline] > kcov_remote_start_usb_softirq include/linux/kcov.h:89 [inline] > __usb_hcd_giveback_urb+0x427/0x710 drivers/usb/core/hcd.c:1662 > usb_giveback_urb_bh+0x296/0x420 drivers/usb/core/hcd.c:1697 > process_one_work kernel/workqueue.c:3236 [inline] > process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 > bh_worker+0x2b1/0x600 kernel/workqueue.c:3579 > tasklet_action+0xc/0x70 kernel/softirq.c:854 > handle_softirqs+0x22f/0x710 kernel/softirq.c:579 > run_ksoftirqd+0xac/0x210 kernel/softirq.c:968 > smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160 > kthread+0x70e/0x8a0 kernel/kthread.c:464 > ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 >