bisecting fixing commit since fb683b5e3f53a73e761952735736180939a313df
building syzkaller on 101194ebf6834198300032f6fb438f2c4cdf0401
testing commit fb683b5e3f53a73e761952735736180939a313df with gcc (GCC) 8.4.1 20210217
kernel signature: d049fcad6b5eab1c475b7345c1aea7ed833ad45a06b5c4a5738bae3eed2a1216
all runs: crashed: kernel BUG in close_fs_devices
testing current HEAD eb575cd5d7f60241d016fdd13a9e86d962093c9b
testing commit eb575cd5d7f60241d016fdd13a9e86d962093c9b with gcc (GCC) 8.4.1 20210217
kernel signature: b9696b4d166bcae8a86a19275b07a247d1348d0ab22c9abd7020ef85e637c52d
all runs: crashed: kernel BUG in close_fs_devices
revisions tested: 2, total time: 24m32.316778324s (build: 17m25.937920083s, test: 6m26.991841065s)
the crash still happens on HEAD
commit msg: Linux 4.19.195
crash: kernel BUG in close_fs_devices
RDX: 00007ff6312cc020 RSI: 00000000200001c0 RDI: 00007ff6312cc040
RBP: 00007ff6312cc040 R08: 00007ff6312cc080 R09: 00007ff6312cc020
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00000000004fd190 R14: 00000000004b6840 R15: 00007ff6312cc6bc
------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:1062!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 6885 Comm: syz-executor.0 Not tainted 4.19.195-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:btrfs_close_one_device fs/btrfs/volumes.c:1062 [inline]
RIP: 0010:close_fs_devices.part.48+0x4ed/0x7a0 fs/btrfs/volumes.c:1081
Code: 9e 01 00 00 48 8d 7a 30 4c 89 43 18 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 6a 01 00 00 48 83 6a 30 01 e9 45 fc ff ff 0f 0b <0f> 0b 4c 89 f7 e8 a9 dc e6 fe e9 a7 fb ff ff e8 9f dc e6 fe e9 a0
RSP: 0018:ffff8881e0517788 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8881e20c3680 RCX: 0000000000000000
RDX: 1ffffffff10a4021 RSI: ffffffff88590260 RDI: 0000000000000282
RBP: ffff8881e05177f8 R08: ffffed103ed04733 R09: ffffed103ed04732
R10: ffffed103ed04732 R11: ffff8881f6823993 R12: dffffc0000000000
R13: ffff8881df619158 R14: ffff8881e20c36a0 R15: ffff8881d70dfb40
FS:  00007ff6312cc700(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9ed124f000 CR3: 00000001d4819005 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 close_fs_devices fs/btrfs/volumes.c:1113 [inline]
 btrfs_close_devices+0x80/0x1b0 fs/btrfs/volumes.c:1099
 btrfs_mount_root+0xeb4/0x16f0 fs/btrfs/super.c:1630
 mount_fs+0x7f/0x2b0 fs/super.c:1261
 vfs_kern_mount.part.34+0x58/0x3d0 fs/namespace.c:961
 vfs_kern_mount+0xe/0x20 fs/namespace.c:947
 btrfs_mount+0x219/0xc00 fs/btrfs/super.c:1681
 mount_fs+0x7f/0x2b0 fs/super.c:1261
 vfs_kern_mount.part.34+0x58/0x3d0 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2469 [inline]
 do_mount+0x36e/0x2410 fs/namespace.c:2799
 ksys_mount+0xb1/0xd0 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xb9/0x150 fs/namespace.c:3026
 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4636da
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 88 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff6312cbfb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 000000000052bf00 RCX: 00000000004636da
RDX: 00007ff6312cc020 RSI: 00000000200001c0 RDI: 00007ff6312cc040
RBP: 00007ff6312cc040 R08: 00007ff6312cc080 R09: 00007ff6312cc020
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00000000004fd190 R14: 00000000004b6840 R15: 00007ff6312cc6bc
Modules linked in:
---[ end trace 2795ed1a61afc42a ]---
RIP: 0010:btrfs_close_one_device fs/btrfs/volumes.c:1062 [inline]
RIP: 0010:close_fs_devices.part.48+0x4ed/0x7a0 fs/btrfs/volumes.c:1081
Code: 9e 01 00 00 48 8d 7a 30 4c 89 43 18 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 6a 01 00 00 48 83 6a 30 01 e9 45 fc ff ff 0f 0b <0f> 0b 4c 89 f7 e8 a9 dc e6 fe e9 a7 fb ff ff e8 9f dc e6 fe e9 a0
RSP: 0018:ffff8881e0517788 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8881e20c3680 RCX: 0000000000000000
RDX: 1ffffffff10a4021 RSI: ffffffff88590260 RDI: 0000000000000282
RBP: ffff8881e05177f8 R08: ffffed103ed04733 R09: ffffed103ed04732
R10: ffffed103ed04732 R11: ffff8881f6823993 R12: dffffc0000000000
R13: ffff8881df619158 R14: ffff8881e20c36a0 R15: ffff8881d70dfb40
FS:  00007ff6312cc700(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faa2c514000 CR3: 00000001d4819004 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400