------------[ cut here ]------------
WARNING: CPU: 0 PID: 8442 at fs/ext4/inode.c:3794 ext4_iomap_begin+0x16c5/0x1900
Modules linked in:
CPU: 0 UID: 0 PID: 8442 Comm: syz.8.261 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:ext4_iomap_begin+0x16c5/0x1900
Code: 24 18 39 c3 0f 42 c3 41 01 c7 41 89 dc e9 3c f5 ff ff e8 8e 35 4c ff c7 44 24 20 09 00 00 00 e9 18 f5 ff ff e8 7c 35 4c ff 90 <0f> 0b 90 41 be de ff ff ff 4c 8b 7c 24 70 e9 18 ed ff ff 89 d9 80
RSP: 0018:ffffc90002d1f0a0 EFLAGS: 00010293
RAX: ffffffff82737614 RBX: ffff88802a7f8050 RCX: ffff888108559cc0
RDX: 0000000000000000 RSI: 00000000000000d4 RDI: 0000000000000000
RBP: ffffc90002d1f238 R08: ffff88802a7f8057 R09: 1ffff110054ff00a
R10: dffffc0000000000 R11: ffffed10054ff00b R12: dffffc0000000000
R13: 1ffff110054ff06b R14: 0000000000000000 R15: 00000000000000d4
FS:  00007f8e3be266c0(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055619ff03008 CR3: 000000010513c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 iomap_iter+0x534/0xde0
 __iomap_dio_rw+0xc57/0x1e30
 iomap_dio_rw+0x45/0xb0
 ext4_file_write_iter+0x16a2/0x1bc0
 iter_file_splice_write+0x975/0x10e0
 direct_splice_actor+0x101/0x160
 splice_direct_to_actor+0x5a8/0xcc0
 do_splice_direct+0x181/0x270
 do_sendfile+0x4da/0x7e0
 __se_sys_sendfile64+0x13e/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e3af8ebe9
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:00007f8e3be26038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f8e3b1b5fa0 RCX: 00007f8e3af8ebe9
RDX: 0000000000000000 RSI: 000000000000003e RDI: 000000000000000a
RBP: 00007f8e3b011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8e3b1b6038 R14: 00007f8e3b1b5fa0 R15: 00007ffee8f01828
 </TASK>
