bisecting fixing commit since 31acccdc877486a649a86d37725a15175fcd5ed6 building syzkaller on cca8798699baeeccbf80af23d234ac19a5d667aa testing commit 31acccdc877486a649a86d37725a15175fcd5ed6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 54d929d8261f7613f13f374e3ee5b29dc866cb32e93f592c6f04b33fc5e1e0ae all runs: crashed: kernel BUG in dnotify_free_mark testing current HEAD 4938296e03bd227e5020d63d418956fe52baf97c testing commit 4938296e03bd227e5020d63d418956fe52baf97c compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 65973ca2e424542a8434e2bbdf25e40085b932ed261d43ca2acf2019b1071658 all runs: crashed: kernel BUG in dnotify_free_mark revisions tested: 2, total time: 27m58.370490287s (build: 20m38.892627429s, test: 6m55.201198664s) the crash still happens on HEAD commit msg: Linux 4.19.198 crash: kernel BUG in dnotify_free_mark wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready ------------[ cut here ]------------ wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 kernel BUG at fs/notify/dnotify/dnotify.c:132! invalid opcode: 0000 [#1] PREEMPT SMP KASAN wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 CPU: 0 PID: 9177 Comm: kworker/u4:7 Not tainted 4.19.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound fsnotify_mark_destroy_workfn RIP: 0010:dnotify_free_mark fs/notify/dnotify/dnotify.c:132 [inline] RIP: 0010:dnotify_free_mark+0x3b/0x50 fs/notify/dnotify/dnotify.c:126 Code: 78 48 89 fa 48 89 e5 48 83 ec 08 48 c1 ea 03 80 3c 02 00 75 17 48 83 7e 78 00 75 0e 48 8b 3d 04 59 15 09 e8 87 1d e7 ff c9 c3 <0f> 0b 48 89 75 f8 e8 ba 56 e7 ff 48 8b 75 f8 eb da 0f 1f 40 00 55 RSP: 0018:ffff8881d2627c68 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: ffff8881eed135c0 RCX: 1ffff1103d9a756b RDX: 1ffff1103d9a7577 RSI: ffff8881ecd3ab40 RDI: ffff8881ecd3abb8 RBP: ffff8881d2627c70 R08: ffff8881d2627cf0 R09: 1ffff1103a4c4f9f R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881ecd3ab40 R13: ffffffff88142dc0 R14: dffffc0000000000 R15: ffff8881ecd3ab40 FS: 0000000000000000(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd54fa7f1c CR3: 000000000986d002 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fsnotify_final_mark_destroy+0x6d/0xa0 fs/notify/mark.c:213 fsnotify_mark_destroy_workfn+0x1d7/0x390 fs/notify/mark.c:799 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Modules linked in: ---[ end trace c7ce7798b2ce5418 ]--- RIP: 0010:dnotify_free_mark fs/notify/dnotify/dnotify.c:132 [inline] RIP: 0010:dnotify_free_mark+0x3b/0x50 fs/notify/dnotify/dnotify.c:126 Code: 78 48 89 fa 48 89 e5 48 83 ec 08 48 c1 ea 03 80 3c 02 00 75 17 48 83 7e 78 00 75 0e 48 8b 3d 04 59 15 09 e8 87 1d e7 ff c9 c3 <0f> 0b 48 89 75 f8 e8 ba 56 e7 ff 48 8b 75 f8 eb da 0f 1f 40 00 55 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready RSP: 0018:ffff8881d2627c68 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: ffff8881eed135c0 RCX: 1ffff1103d9a756b ieee80211 phy10: Selected rate control algorithm 'minstrel_ht' RDX: 1ffff1103d9a7577 RSI: ffff8881ecd3ab40 RDI: ffff8881ecd3abb8 RBP: ffff8881d2627c70 R08: ffff8881d2627cf0 R09: 1ffff1103a4c4f9f R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881ecd3ab40 ieee80211 phy11: Selected rate control algorithm 'minstrel_ht' R13: ffffffff88142dc0 R14: dffffc0000000000 R15: ffff8881ecd3ab40 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready FS: 0000000000000000(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd2d5cac60 CR3: 000000000986d005 CR4: 00000000001606e0 ieee80211 phy12: Selected rate control algorithm 'minstrel_ht' wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 ieee80211 phy13: Selected rate control algorithm 'minstrel_ht' wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50