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WARNING: CPU: 3 PID: 375 at fs/buffer.c:1128 mark_buffer_dirty+0x4fa/0x690 fs/buffer.c:1128
Kernel panic - not syncing: panic_on_warn set ...
CPU: 3 PID: 375 Comm: kworker/u17:6 Not tainted 5.6.0-rc4-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x35 kernel/panic.c:582
 report_bug+0x27b/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:mark_buffer_dirty+0x4fa/0x690 fs/buffer.c:1128
Code: 03 80 3c 02 00 0f 85 99 01 00 00 48 8b 3b be 04 00 00 00 e8 08 e5 fc ff 5b 5d 41 5c 41 5d 41 5e e9 8b d6 a9 ff e8 86 d6 a9 ff <0f> 0b e9 4f fb ff ff e8 7a d6 a9 ff 0f 0b e9 73 fb ff ff e8 6e d6
RSP: 0018:ffffc90001a37010 EFLAGS: 00010293
RAX: ffff888029c38200 RBX: ffff888026366888 RCX: ffffffff81c83827
RDX: 0000000000000000 RSI: ffffffff81c83cda RDI: 0000000000000001
RBP: 0000000000000000 R08: ffff888029c38200 R09: ffffed1004c6cd12
R10: ffffed1004c6cd11 R11: ffff88802636688f R12: 0000000000000000
R13: 0000000000000000 R14: ffff8880280d5380 R15: ffff888023f1a03c
 __ext4_handle_dirty_metadata+0x41d/0x7a0 fs/ext4/ext4_jbd2.c:338
 ext4_mb_mark_diskspace_used+0x943/0x10e0 fs/ext4/mballoc.c:3048
 ext4_mb_new_blocks+0xb25/0x3930 fs/ext4/mballoc.c:4579
 ext4_ext_map_blocks+0x221c/0x37d0 fs/ext4/extents.c:4440
 ext4_map_blocks+0x4cb/0x1650 fs/ext4/inode.c:622
 mpage_map_one_extent fs/ext4/inode.c:2365 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2418 [inline]
 ext4_writepages+0x19eb/0x3080 fs/ext4/inode.c:2772
 do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344
 __writeback_single_inode+0x12a/0x1410 fs/fs-writeback.c:1452
 writeback_sb_inodes+0x515/0xdd0 fs/fs-writeback.c:1716
 __writeback_inodes_wb+0xc3/0x250 fs/fs-writeback.c:1785
 wb_writeback+0x910/0xd90 fs/fs-writeback.c:1894
 wb_check_background_flush fs/fs-writeback.c:1962 [inline]
 wb_do_writeback fs/fs-writeback.c:2050 [inline]
 wb_workfn+0xa49/0x11c0 fs/fs-writeback.c:2078
 process_one_work+0x94b/0x1690 kernel/workqueue.c:2264
 worker_thread+0x96/0xe20 kernel/workqueue.c:2410
 kthread+0x357/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..