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kernel BUG at fs/ext4/inode.c:2809!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 4422 Comm: kworker/u9:7 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
Workqueue: writeback wb_workfn (flush-7:5)
RIP: 0010:ext4_do_writepages+0x4607/0x4610
Code: c6 c0 79 9e 8b e8 99 9f b4 fe 90 0f 0b e8 11 4f 4c ff 4c 89 f7 48 c7 c6 a0 7d 9e 8b e8 82 9f b4 fe 90 0f 0b e8 fa 4e 4c ff 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90007f9ecc0 EFLAGS: 00010293
RAX: ffffffff82735c96 RBX: 0000004210000000 RCX: ffff8880246bd640
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc90007f9f0f0 R08: ffff888030e97317 R09: 1ffff110061d2e62
R10: dffffc0000000000 R11: ffffed10061d2e63 R12: 0000000000000001
R13: ffffc90007f9f140 R14: 0000004000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb98e06d000 CR3: 0000000108bba000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 ext4_writepages+0x205/0x350
 do_writepages+0x32e/0x550
 __writeback_single_inode+0x145/0xff0
 writeback_sb_inodes+0x6c7/0x1010
 wb_writeback+0x43b/0xaf0
 wb_workfn+0x409/0xef0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_do_writepages+0x4607/0x4610
Code: c6 c0 79 9e 8b e8 99 9f b4 fe 90 0f 0b e8 11 4f 4c ff 4c 89 f7 48 c7 c6 a0 7d 9e 8b e8 82 9f b4 fe 90 0f 0b e8 fa 4e 4c ff 90 <0f> 0b 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90007f9ecc0 EFLAGS: 00010293
RAX: ffffffff82735c96 RBX: 0000004210000000 RCX: ffff8880246bd640
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc90007f9f0f0 R08: ffff888030e97317 R09: 1ffff110061d2e62
R10: dffffc0000000000 R11: ffffed10061d2e63 R12: 0000000000000001
R13: ffffc90007f9f140 R14: 0000004000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005575ef422131 CR3: 00000000239d0000 CR4: 00000000000006f0
