BTRFS info (device loop0: state C): enabling ssd optimizations
BTRFS info (device loop0: state C): auto enabling async discard
BTRFS error (device loop0: state MC): nologreplay must be used with ro mount option
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 PID: 5935 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:backup_super_roots fs/btrfs/disk-io.c:1668 [inline]
RIP: 0010:write_all_supers+0x8a7/0x3e60 fs/btrfs/disk-io.c:4079
Code: 10 48 8d 9a 9a 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 53 33 00 00 44 88 33 49 83 c4 18 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 0d 4c 89 e7 e8 2a be 66 fe 48 8b 54 24 10 49 8b
RSP: 0018:ffffc900033f7400 EFLAGS: 00010206
RAX: 0000000000000003 RBX: ffff888079748bc5 RCX: 0000000000000000
RDX: ffff888079748b2b RSI: 0000000000000004 RDI: ffff888076f12a50
RBP: ffffc900033f77b0 R08: ffff888030bcc063 R09: 1ffff1100617980c
R10: dffffc0000000000 R11: ffffed100617980d R12: 0000000000000018
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888023802018
FS: 0000555570885500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558ef9c265f8 CR3: 000000005ff8e000 CR4: 00000000003506e0
Call Trace:
<TASK>
btrfs_commit_transaction+0x1e95/0x3760 fs/btrfs/transaction.c:2516
btrfs_set_free_space_cache_v1_active+0x71/0x1c0 fs/btrfs/free-space-cache.c:4151
btrfs_remount_cleanup fs/btrfs/super.c:1684 [inline]
btrfs_remount+0x6cc/0x1470 fs/btrfs/super.c:1880
reconfigure_super+0x21e/0x880 fs/super.c:1151
do_remount fs/namespace.c:2927 [inline]
path_mount+0xd19/0xfe0 fs/namespace.c:3705
do_mount fs/namespace.c:3726 [inline]
__do_sys_mount fs/namespace.c:3935 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3912
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f76d7b8f749
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:00007fff0196c188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f76d7de5fa0 RCX: 00007f76d7b8f749
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000000
RBP: 00007f76d7c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000020 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76d7de5fa0 R14: 00007f76d7de5fa0 R15: 0000000000000005
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:backup_super_roots fs/btrfs/disk-io.c:1668 [inline]
RIP: 0010:write_all_supers+0x8a7/0x3e60 fs/btrfs/disk-io.c:4079
Code: 10 48 8d 9a 9a 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 53 33 00 00 44 88 33 49 83 c4 18 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 0d 4c 89 e7 e8 2a be 66 fe 48 8b 54 24 10 49 8b
RSP: 0018:ffffc900033f7400 EFLAGS: 00010206
RAX: 0000000000000003 RBX: ffff888079748bc5 RCX: 0000000000000000
RDX: ffff888079748b2b RSI: 0000000000000004 RDI: ffff888076f12a50
RBP: ffffc900033f77b0 R08: ffff888030bcc063 R09: 1ffff1100617980c
R10: dffffc0000000000 R11: ffffed100617980d R12: 0000000000000018
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888023802018
FS: 0000555570885500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2c00174000 CR3: 000000005ff8e000 CR4: 00000000003506f0
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 48 8d 9a 9a 00 00 00 lea 0x9a(%rdx),%rbx
7: 48 89 d8 mov %rbx,%rax
a: 48 c1 e8 03 shr $0x3,%rax
e: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax
13: 84 c0 test %al,%al
15: 0f 85 53 33 00 00 jne 0x336e
1b: 44 88 33 mov %r14b,(%rbx)
1e: 49 83 c4 18 add $0x18,%r12
22: 4c 89 e0 mov %r12,%rax
25: 48 c1 e8 03 shr $0x3,%rax
* 29: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction
2e: 74 0d je 0x3d
30: 4c 89 e7 mov %r12,%rdi
33: e8 2a be 66 fe call 0xfe66be62
38: 48 8b 54 24 10 mov 0x10(%rsp),%rdx
3d: 49 rex.WB
3e: 8b .byte 0x8b