bisecting fixing commit since 2b79150141611d3c6e1b55d4e70f49602482f0b8 building syzkaller on 18e33098d58c8738cc3b678346141b74d34d4e30 testing commit 2b79150141611d3c6e1b55d4e70f49602482f0b8 with gcc (GCC) 8.1.0 kernel signature: d84038874c6566a8e95425d54115f5830735998d266ae0bb4a7615c9ea4c5009 all runs: crashed: kernel BUG at fs/notify/dnotify/dnotify.c:LINE! testing current HEAD 1752938529c614a8ed4432ecce6ebc95d3b87207 testing commit 1752938529c614a8ed4432ecce6ebc95d3b87207 with gcc (GCC) 8.1.0 kernel signature: 8b4787bb6286aef31258aab63b6e581f6fb8f0ececf0471eeb63cc687fbcd64a all runs: crashed: kernel BUG at fs/notify/dnotify/dnotify.c:LINE! revisions tested: 2, total time: 21m50.11303662s (build: 15m53.50089123s, test: 5m28.981838266s) the crash still happens on HEAD commit msg: Linux 4.14.213 crash: kernel BUG at fs/notify/dnotify/dnotify.c:LINE! wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 device veth1_macvtap entered promiscuous mode ------------[ cut here ]------------ IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready kernel BUG at fs/notify/dnotify/dnotify.c:131! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 invalid opcode: 0000 [#1] PREEMPT SMP KASAN batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! Modules linked in: batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 CPU: 0 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.213-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound fsnotify_mark_destroy_workfn task: ffff8881f531c140 task.stack: ffff8881f5328000 RIP: 0010:dnotify_free_mark+0x3b/0x50 fs/notify/dnotify/dnotify.c:131 RSP: 0018:ffff8881f532fc70 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: ffff8881ef3287c0 RCX: 1ffff1103d11dd6b RDX: 1ffff1103d11dd77 RSI: ffff8881e88eeb40 RDI: ffff8881e88eebb8 RBP: ffff8881f532fc78 R08: ffff8881f532fcf8 R09: 1ffff1103ea65fa0 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881e88eeb40 R13: ffffffff87938360 R14: dffffc0000000000 R15: ffff8881e88eeb40 FS: 0000000000000000(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e72a581140 CR3: 0000000008e6a004 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fsnotify_final_mark_destroy+0x72/0xa0 fs/notify/mark.c:192 fsnotify_mark_destroy_workfn+0x1cf/0x370 fs/notify/mark.c:761 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xed0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: c7 78 48 89 fa 48 89 e5 48 83 ec 08 48 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! c1 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 ea 03 80 3c 02 00 75 17 48 83 7e 78 00 75 0e 48 8b 3d e4 47 72 08 e8 a7 97 e9 ff c9 c3 <0f> 0b 48 89 75 f8 e8 da cd e9 ff 48 8b 75 f8 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! eb da 0f 1f 40 00 RIP: dnotify_free_mark+0x3b/0x50 fs/notify/dnotify/dnotify.c:131 RSP: ffff8881f532fc70 ---[ end trace 829a6d974dd9293c ]--- batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0