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WARNING: CPU: 1 PID: 26665 at fs/buffer.c:634 __set_page_dirty+0x188/0x1f0 fs/buffer.c:634
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 26665 Comm: syz-executor.2 Not tainted 4.9.141+ #1
 ffff8801d27077b0 ffffffff81b42e79 ffffffff82a38ce0 00000000ffffffff
 ffffffff82ab7700 0000000000000001 0000000000000009 ffff8801d2707870
 ffffffff813f7125 0000000041b58ab3 ffffffff82e2b62b ffffffff813f6f66
Call Trace:
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff813f7125>] panic+0x1bf/0x39f kernel/panic.c:179
 [<ffffffff813f7362>] __warn.cold.8+0x2f/0x2f kernel/panic.c:542
 [<ffffffff810dc02c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff815b81b8>] __set_page_dirty+0x188/0x1f0 fs/buffer.c:634
 [<ffffffff815b8379>] __set_page_dirty_buffers+0x159/0x230 fs/buffer.c:694
 [<ffffffff8142ca32>] set_page_dirty+0x162/0x2d0 mm/page-writeback.c:2554
 [<ffffffff815c2636>] block_page_mkwrite+0x206/0x2c0 fs/buffer.c:2510
 [<ffffffff816e72cd>] ext4_page_mkwrite+0xbfd/0xfe0 fs/ext4/inode.c:5778
 [<ffffffff81492ab5>] do_page_mkwrite+0x1c5/0x3e0 mm/memory.c:2061
 [<ffffffff81497be5>] wp_page_shared mm/memory.c:2326 [inline]
 [<ffffffff81497be5>] do_wp_page+0xf45/0x2010 mm/memory.c:2430
 [<ffffffff814a333b>] handle_pte_fault mm/memory.c:3531 [inline]
 [<ffffffff814a333b>] __handle_mm_fault mm/memory.c:3603 [inline]
 [<ffffffff814a333b>] handle_mm_fault+0xfcb/0x2350 mm/memory.c:3640
 [<ffffffff810b2b33>] __do_page_fault+0x403/0xa60 arch/x86/mm/fault.c:1406
 [<ffffffff810b31e7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff828188b5>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:951
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..