From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (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 C70591DD543 for ; Thu, 21 Aug 2025 02:14:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755742474; cv=none; b=QTPt3NrwvGyUeaBqgLwtd0+YoeSTBsJ12lTyMnKKu1GZ57lCrcL2AgSbGd0sNO+ZZP/JGJGDiQtVgescAzx9d0rkqRUtW3v9QemsZJAOVhFkSta/+Nklrc8fxDV31g1mBkd/42ifhXvBrPqbv8LPtAq2HvPRow+yajDgqyvc1xM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755742474; c=relaxed/simple; bh=c1JzjzcqhHeqb50RUyDDT9Y98mtiHK/L6+DIp7oHAW8=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=e32VpbwiUAdgftwRcxfP+hE0kgL2gc8T0clBhs/d0Va/Q5jC/jm74AHDow2gX8PVXwXEqBvX9huxptIiFz8NLaybn5XuSipycrrB+QclQ64jfNe9umh917qol4doWytZ2D+kXyIThkhzjhc7mGnRCPNVvCZZmdzqF4JBc798FEk= 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=209.85.166.206 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-il1-f206.google.com with SMTP id e9e14a558f8ab-3e6e61caf71so5957685ab.3 for ; Wed, 20 Aug 2025 19:14:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755742472; x=1756347272; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=aQxHRgeChNTxbLV3131Rwb52VhDI/1dYJc8+5cwgx30=; b=Sz/RN2GpzagDFOcQUnudi4eh2ctYt/WVfbCAHlU4+UMa4eld2TqUcAVbLgAi7SNaOc kBm4PvmJjTmXU4frxi+BV9aTxz38ZG6XC0WwSQJa4J9L2ZvoYNEZLoFqt4ii1JGR1E/O d7GUwgrzVmIlVnE2olto1ee+Vh+P0985zkLa9asjV9ZsdSoSdQ+RLruo0xMjNjf0CWhz x7PnHCfXCpSnD6MY+foNhrXxOts48ItQjcfSZkjta1X7MJdbB/NT8PD3nYPRuXAlOHWn nIeONksRCyYsZG3qoRzrYHJOiGZ6FRhV+QwiPSIT5Z1i2+9UYky26fzKMY0qid+FADF0 uTWA== X-Forwarded-Encrypted: i=1; AJvYcCVavxT/D/TfjRBgBWdAQC1WDARy/YjpnuEMLr8wp3dTxzI49QcmHhBm+GmS/hBEmrZr7yiCUpVnyz4/k8Y=@vger.kernel.org X-Gm-Message-State: AOJu0Yz73HlpJha8H5v0mCwo9ffDC5kJuOUkpRQuH7Z35QUKE/2dtJUz 2J8526JHsiEZHBFoCSkj7u+54NvQyhgXztcc6LZSRdY3Yd7ABcfptklqQoGlprb8YEgmcLrxHE0 nsGz408+yWsWWCypGrnJ7ofoAzcrRlfmNLKpLhn3JPfLJgLNIheyG3Wmu56w= X-Google-Smtp-Source: AGHT+IHGC44FrRLwYHhyTjthukMc8igcR3mKads8/zioUjdqWD2TAcdwPDOGULm4I7iJqaRzfo/oKWobKAXoZpW4bMxv5gyafIMf Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:158b:b0:3e5:8249:e973 with SMTP id e9e14a558f8ab-3e6d7b4aa01mr14110555ab.16.1755742471892; Wed, 20 Aug 2025 19:14:31 -0700 (PDT) Date: Wed, 20 Aug 2025 19:14:31 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <68a68107.050a0220.1f0557.0000.GAE@google.com> Subject: [syzbot] [mm?] INFO: rcu detected stall in hub_event (2) From: syzbot To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, pasha.tatashin@soleen.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 90d970cade8e Merge tag 'ata-ata-6.17-rc2' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1193b3a2580000 kernel config: https://syzkaller.appspot.com/x/.config?x=c5d01e11121d45 dashboard link: https://syzkaller.appspot.com/bug?extid=039eab266c6321a174bd compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/104fc9d3de89/disk-90d970ca.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/59eb5344d41f/vmlinux-90d970ca.xz kernel image: https://storage.googleapis.com/syzbot-assets/e0bed540b10c/bzImage-90d970ca.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+039eab266c6321a174bd@syzkaller.appspotmail.com rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9643/1:b..l rcu: (detected by 1, t=10503 jiffies, g=87629, q=1145 ncpus=2) task:kworker/1:13 state:R running task stack:22384 pid:9643 tgid:9643 ppid:2 task_flags:0x4288060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:246 Code: 8b 05 58 b3 1a 12 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 3c 16 00 00 85 c0 74 4f <8b> 82 18 16 00 00 83 f8 03 75 44 48 8b 82 20 16 00 00 8b 92 1c 16 RSP: 0000:ffffc90004fdf430 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000004 RCX: ffffffff822dbf07 RDX: ffff88802883a440 RSI: 0000000000000004 RDI: 0000000000000006 RBP: 0000000000000003 R08: 0000000000000006 R09: 0000000000000004 R10: 0000000000000003 R11: 00000000000082fe R12: ffff8880200096f0 R13: ffff8880200096ec R14: 0000000000000002 R15: dffffc0000000000 __page_table_check_zero+0x207/0x5d0 mm/page_table_check.c:139 page_table_check_free include/linux/page_table_check.h:43 [inline] free_pages_prepare mm/page_alloc.c:1396 [inline] __free_frozen_pages+0x7b7/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4281 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1336 [inline] alloc_uevent_skb+0x7d/0x210 lib/kobject_uevent.c:289 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline] kobject_uevent_env+0xca4/0x1870 lib/kobject_uevent.c:608 device_del+0x623/0x9f0 drivers/base/core.c:3896 usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x9c0 drivers/usb/core/hub.c:2344 hub_port_connect drivers/usb/core/hub.c:5406 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x1c81/0x4fe0 drivers/usb/core/hub.c:5952 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup