blk_update_request: I/O error, dev loop0, sector 32
Buffer I/O error on dev loop0, logical block 8, lost async page write
blk_update_request: I/O error, dev loop0, sector 36
Buffer I/O error on dev loop0, logical block 9, lost async page write
------------[ cut here ]------------
WARNING: CPU: 0 PID: 29053 at fs/buffer.c:1150 mark_buffer_dirty+0x26c/0x480 fs/buffer.c:1150
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 29053 Comm: syz-executor4 Not tainted 4.9.144+ #77
 ffff88019b5cf3f0 ffffffff81b43b89 ffffffff82a39060 00000000ffffffff
 ffffffff82ab7b00 0000000000000000 0000000000000009 ffff88019b5cf4b0
 ffffffff813f7575 0000000041b58ab3 ffffffff82e2e82b ffffffff813f73b6
Call Trace:
 [<ffffffff81b43b89>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b43b89>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff813f7575>] panic+0x1bf/0x39f kernel/panic.c:179
 [<ffffffff813f77b2>] __warn.cold.8+0x2f/0x2f kernel/panic.c:542
 [<ffffffff810dc0bc>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff815b8f3c>] mark_buffer_dirty+0x26c/0x480 fs/buffer.c:1150
 [<ffffffff815bbc7c>] __block_commit_write.isra.10+0x13c/0x200 fs/buffer.c:2061
 [<ffffffff815bbd8a>] block_write_end+0x4a/0x100 fs/buffer.c:2139
 [<ffffffff815c7239>] blkdev_write_end+0x49/0x120 fs/block_dev.c:339
 [<ffffffff8140fb0c>] generic_perform_write+0x34c/0x500 mm/filemap.c:2764
 [<ffffffff81412992>] __generic_file_write_iter+0x352/0x540 mm/filemap.c:2878
 [<ffffffff815cb637>] blkdev_write_iter+0x1b7/0x370 fs/block_dev.c:1718
 [<ffffffff81507447>] vfs_iter_write+0x2d7/0x450 fs/read_write.c:390
 [<ffffffff815aed7b>] iter_file_splice_write+0x5fb/0xb30 fs/splice.c:768
 [<ffffffff815aa338>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff815aa338>] direct_splice_actor+0x128/0x190 fs/splice.c:1037
 [<ffffffff815abf41>] splice_direct_to_actor+0x2c1/0x7e0 fs/splice.c:992
 [<ffffffff815ac603>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff8150da00>] do_sendfile+0x4f0/0xc30 fs/read_write.c:1393
 [<ffffffff8150fa71>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff8150fa71>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82818cd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Kernel Offset: disabled
Rebooting in 86400 seconds..