bisecting fixing commit since a1b977b49b66c75e6c51a515f6700371ae720217
building syzkaller on 1880b4a9f394370a7d1fcb5c1cfca0fa1127b463
testing commit a1b977b49b66c75e6c51a515f6700371ae720217 with gcc (GCC) 8.1.0
kernel signature: ce2ecfcb8b01f3b5cb6c337e1edad9dcf00eb37275f9b67b3cf65b0bbc2d1954
run #0: crashed: WARNING in drop_nlink
run #1: crashed: WARNING in drop_nlink
run #2: crashed: WARNING in drop_nlink
run #3: crashed: WARNING in drop_nlink
run #4: crashed: WARNING in corrupted
run #5: crashed: WARNING in drop_nlink
run #6: crashed: WARNING in drop_nlink
run #7: crashed: WARNING in drop_nlink
run #8: crashed: WARNING in drop_nlink
run #9: crashed: WARNING in drop_nlink
testing current HEAD 3207316b3beec7e38e5dbe2f463df0cec71e0b97
testing commit 3207316b3beec7e38e5dbe2f463df0cec71e0b97 with gcc (GCC) 8.1.0
kernel signature: 8526c5a8026770c11e62397c14a4ebae2a5ea09fef8ae29f8c81c33d267594fe
all runs: crashed: WARNING in drop_nlink
revisions tested: 2, total time: 25m24.678034791s (build: 19m5.642184124s, test: 5m42.05482594s)
the crash still happens on HEAD
commit msg: Linux 4.19.164
crash: WARNING in drop_nlink
Bluetooth: hci3: command 0x0419 tx timeout
Bluetooth: hci5: command 0x0419 tx timeout
Bluetooth: hci1: command 0x0419 tx timeout
MINIX-fs: mounting unchecked file system, running fsck is recommended
------------[ cut here ]------------
WARNING: CPU: 0 PID: 7446 at fs/inode.c:286 drop_nlink.cold.19+0xc/0x3c fs/inode.c:286
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7446 Comm: syz-executor.2 Not tainted 4.19.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x17c/0x22a lib/dump_stack.c:118
 panic+0x1cd/0x375 kernel/panic.c:186
 __warn.cold.7+0x1b/0x3e kernel/panic.c:541
 report_bug+0x1a4/0x200 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:drop_nlink.cold.19+0xc/0x3c fs/inode.c:286
Code: e0 2a 80 3c 02 00 75 0c 48 8b 83 d0 00 00 00 e9 ef b8 ff ff 4c 89 e7 e8 35 c3 f0 ff eb ea 48 c7 c7 c0 b1 53 87 e8 67 53 ad ff <0f> 0b b8 ff ff 37 00 4c 89 e2 48 c1 ea 03 48 c1 e0 2a 0f b6 04 02
RSP: 0018:ffff8881cd9079e0 EFLAGS: 00010282
RAX: 0000000000000024 RBX: ffff8881c705f0c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff878b5c00 RDI: ffffffff8a3e3a60
RBP: ffff8881cd9079f8 R08: ffffed103ecc5081 R09: ffffed103ecc5080
R10: ffffed103ecc5080 R11: ffff8881f6628407 R12: ffff8881c705f108
R13: ffff8881c70609e0 R14: 0000000000000000 R15: ffff8881c7819080
 inode_dec_link_count include/linux/fs.h:2108 [inline]
 minix_rename+0x330/0x720 fs/minix/namei.c:226
 vfs_rename+0xa13/0x1860 fs/namei.c:4479
 do_renameat2+0x60d/0xa00 fs/namei.c:4629
 __do_sys_renameat fs/namei.c:4670 [inline]
 __se_sys_renameat fs/namei.c:4667 [inline]
 __x64_sys_renameat+0x95/0xf0 fs/namei.c:4667
 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45de29
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f04e3badc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000108
RAX: ffffffffffffffda RBX: 00000000000272c0 RCX: 000000000045de29
RDX: 0000000000000009 RSI: 0000000020000500 RDI: 000000000000000a
RBP: 000000000118bf68 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200017c0 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fff657e496f R14: 00007f04e3bae9c0 R15: 000000000118bf2c
Kernel Offset: disabled
Rebooting in 86400 seconds..