qnx6: unable to read the first superblock
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6160 at fs/buffer.c:1125 __getblk_slow+0x4cc/0x560 fs/buffer.c:1125
Modules linked in:
CPU: 1 UID: 0 PID: 6160 Comm: syz.5.57 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__getblk_slow+0x4cc/0x560 fs/buffer.c:1125
Code: 80 8b 48 89 df e8 14 d2 ba ff 90 0f 0b e8 dc c0 71 ff 48 c7 c6 20 84 80 8b 48 89 df e8 fd d1 ba ff 90 0f 0b e8 c5 c0 71 ff 90 <0f> 0b 90 8b 74 24 0c 89 ea 48 c7 c7 80 85 80 8b 31 db e8 8d 62 50
RSP: 0018:ffffc90002f87a88 EFLAGS: 00010283
RAX: 0000000000005a4c RBX: 0000000000000200 RCX: ffffc9000e4c3000
RDX: 0000000000080000 RSI: ffffffff8249749b RDI: 0000000000000005
RBP: 0000000000000400 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000000 R12: ffff888148d83980
R13: 0000000000000000 R14: 0000000000000200 R15: ffff888148d83980
FS:  00007f23714366c0(0000) GS:ffff888124f88000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31c11ff8 CR3: 0000000079177000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 bdev_getblk+0xd4/0xe0 fs/buffer.c:1461
 __bread_gfp+0x86/0x3c0 fs/buffer.c:1515
 sb_bread include/linux/buffer_head.h:346 [inline]
 qnx6_check_first_superblock+0xab/0x2d0 fs/qnx6/inode.c:260
 qnx6_fill_super+0xd8d/0x1520 fs/qnx6/inode.c:332
 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1692
 vfs_get_tree+0x8e/0x340 fs/super.c:1752
 do_new_mount fs/namespace.c:3750 [inline]
 path_mount+0x1516/0x2060 fs/namespace.c:4065
 do_mount fs/namespace.c:4078 [inline]
 __do_sys_mount fs/namespace.c:4278 [inline]
 __se_sys_mount fs/namespace.c:4255 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f237058eec9
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:00007f2371436038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f23707e6090 RCX: 00007f237058eec9
RDX: 0000200000000040 RSI: 0000200000004a00 RDI: 0000200000000000
RBP: 00007f2370611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000002008087 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f23707e6128 R14: 00007f23707e6090 R15: 00007ffd6d7b9478
 </TASK>