From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f205.google.com (mail-il1-f205.google.com [209.85.166.205]) (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 5D25B26F291 for ; Mon, 3 Nov 2025 13:29:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.205 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762176575; cv=none; b=qE0dmkcHDD8HshbyC/l7+HWOGotzh20oGv0LHKy1/8IcR/O8/Iu966US0mnB04rj+Cm6qIGwgvr7Ml6svD0XkHiCN0iSJ3/jjpbuwK5aBr3t6yD3xHAoPbrBJA5tePFsjDkYOP981Y87GnfqG2f0eljxCga8tvWSvRuHTOYqDDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762176575; c=relaxed/simple; bh=nL4Enrsj6XIoiKW42Qd2q2iyP/xMDQnjnqR1eEr95U0=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=jD+ekWw63+hr2Y9ZY99tpLb4a0w8MAGBtyINNBeyWAXVEiwBIeh6oZP7CXLyowtoGvR2fhWhm7yRCbyhIFIGv9UMIhl4xxW8DCmXXeaOm2+D2OFrdW4sg1ZFjAPp418kL3LFUMIZLO3wyqdkrMbETSGSaCWKdEEqZ3PxPoQIKPc= 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=209.85.166.205 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-f205.google.com with SMTP id e9e14a558f8ab-4332b83308fso9836175ab.1 for ; Mon, 03 Nov 2025 05:29:33 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762176572; x=1762781372; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=zqiq2pFuvImBAREJJUY/vzISXNjcGWyY/zRuQ8Cth60=; b=jwbx1pPrj4EhhIJ5y1Dn4A923NiGQLxmbjH7cqvtZfOUHYFcmub6KwvA7YvFhIarQu CvjsglpURK39wJfhlAzOv0Yr7/uF2E0G0Hz47Au7v4s25j7LXpaNOjsKRiSi4u4dlKXg doOQk/o5grJhnFoMabCA6/skZLkctqdAUDb2SjlxO8wB65WaxTRqEdMihPs6udrZtHzH hNTrteWrRNy5ol6K5oSZ82wnyuK+4tZ8Eq0zR8VmvYlMxyiQgDrEgHeKYh/KjpiPuzFA Z5OBR/ERX2MjfIwPC8VMDBNyRgzNNCanL10F/SoA6s6+HseMZ1A0eeB0oMGekJ/FOWo/ yLUQ== X-Forwarded-Encrypted: i=1; AJvYcCVSWdg1a/1d9VehkLT3wg/MwXlIUPEVnoWb6yy/uAFiWLqPfA4R3u90R8KCr/6q49GPSkperGcaXS4A9Qk=@vger.kernel.org X-Gm-Message-State: AOJu0Yy3o1qVOjuk03UjDhsWB8IiT46Nvir5GRwroV3n6LOeTya5JqKI 6qGt1TSRtnKqNs6mhN54c26pY4HbW+frLIIkGl8kW+OGX6iNo7+iT3lc2ceI/fO/K1+4KDLIBc4 U2wi301zfT8GRPgIcFvCapiOiegCMTL+UAKVhTrG9DWO3zZdGcu3THabTgKk= X-Google-Smtp-Source: AGHT+IG2Ta/xKw8mDF5MxXL7PEC6/jFhZNveCmW39DdpHE5LxYHjnbYRJV+pvxt3Ezx7ctafIAhYUOIW/+FgPpy50X692sVjQbLY Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1a28:b0:430:c17c:5082 with SMTP id e9e14a558f8ab-4330d125b63mr172004405ab.6.1762176572541; Mon, 03 Nov 2025 05:29:32 -0800 (PST) Date: Mon, 03 Nov 2025 05:29:32 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6908ae3c.050a0220.29fc44.004b.GAE@google.com> Subject: [syzbot] [net?] possible deadlock in __netdev_update_features (2) From: syzbot To: andrew@lunn.ch, davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 6146a0f1dfae Linux 6.18-rc4 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17b18012580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e46b8a1c645465a9 dashboard link: https://syzkaller.appspot.com/bug?extid=f900128d760321f31225 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/c84c238d0311/disk-6146a0f1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9ce2b6a4b897/vmlinux-6146a0f1.xz kernel image: https://storage.googleapis.com/syzbot-assets/3e9c6bea4a10/bzImage-6146a0f1.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f900128d760321f31225@syzkaller.appspotmail.com ============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.1.3525/19446 is trying to acquire lock: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_sync_lower_features net/core/dev.c:10737 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: __netdev_update_features+0xcb1/0x1be0 net/core/dev.c:10907 but task is already holding lock: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: __dev_ethtool net/ethtool/ioctl.c:3285 [inline] ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: dev_ethtool+0x716/0x19c0 net/ethtool/ioctl.c:3554 and the lock comparison function returns 0: other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev_instance_lock_key#20); lock(&dev_instance_lock_key#20); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz.1.3525/19446: #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: dev_ethtool+0x1d0/0x19c0 net/ethtool/ioctl.c:3553 #1: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2765 [inline] #1: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: __dev_ethtool net/ethtool/ioctl.c:3285 [inline] #1: ffff888070d30d38 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: dev_ethtool+0x716/0x19c0 net/ethtool/ioctl.c:3554 stack backtrace: CPU: 0 UID: 0 PID: 19446 Comm: syz.1.3525 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3895 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 netdev_lock include/linux/netdevice.h:2765 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] netdev_sync_lower_features net/core/dev.c:10737 [inline] __netdev_update_features+0xcb1/0x1be0 net/core/dev.c:10907 netdev_change_features+0x72/0xd0 net/core/dev.c:10981 bond_compute_features+0x615/0x680 drivers/net/bonding/bond_main.c:1559 bond_slave_netdev_event drivers/net/bonding/bond_main.c:4030 [inline] bond_netdev_event+0x72e/0xe80 drivers/net/bonding/bond_main.c:4075 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] netdev_features_change+0x85/0xc0 net/core/dev.c:1570 __dev_ethtool net/ethtool/ioctl.c:3521 [inline] dev_ethtool+0x1541/0x19c0 net/ethtool/ioctl.c:3554 dev_ioctl+0x392/0x1150 net/core/dev_ioctl.c:773 sock_do_ioctl+0x22c/0x300 net/socket.c:1268 sock_ioctl+0x576/0x790 net/socket.c:1375 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc1a3f8efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc1a4e6f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc1a41e5fa0 RCX: 00007fc1a3f8efc9 RDX: 0000200000000000 RSI: 0000000000008946 RDI: 0000000000000004 RBP: 00007fc1a4011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc1a41e6038 R14: 00007fc1a41e5fa0 R15: 00007fc1a430fa28 --- 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