syzbot

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WARNING: CPU: 1 PID: 20099 at fs/ext4/inode.c:922 ext4_dio_get_block_overwrite fs/ext4/inode.c:922 [inline]
WARNING: CPU: 1 PID: 20099 at fs/ext4/inode.c:922 ext4_dio_get_block_overwrite+0x103/0x120 fs/ext4/inode.c:907
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 20099 Comm: syz-executor.2 Not tainted 4.9.194+ #0
 ffff88009e206ec8 ffffffff81b67001 0000000000000000 ffffffff82a3b3c0
 00000000ffffffff 0000000000000001 0000000000000009 ffff88009e206fa8
 ffffffff813fef3a 0000000041b58ab3 ffffffff82e32f55 ffffffff813fed61
Call Trace:
 [<0000000006c64533>] __dump_stack lib/dump_stack.c:15 [inline]
 [<0000000006c64533>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<00000000e059f187>] panic+0x1d9/0x3bd kernel/panic.c:180
 [<0000000040bb5212>] __warn.cold+0x2f/0x2f kernel/panic.c:546
 [<000000005a021790>] warn_slowpath_null+0x2d/0x40 kernel/panic.c:589
 [<00000000eeb143ba>] ext4_dio_get_block_overwrite fs/ext4/inode.c:922 [inline]
 [<00000000eeb143ba>] ext4_dio_get_block_overwrite+0x103/0x120 fs/ext4/inode.c:907
 [<000000004b8ba194>] get_more_blocks fs/direct-io.c:654 [inline]
 [<000000004b8ba194>] do_direct_IO fs/direct-io.c:956 [inline]
 [<000000004b8ba194>] do_blockdev_direct_IO fs/direct-io.c:1275 [inline]
 [<000000004b8ba194>] __blockdev_direct_IO+0x3232/0xd370 fs/direct-io.c:1361
 [<000000003d7306a6>] ext4_direct_IO_write fs/ext4/inode.c:3504 [inline]
 [<000000003d7306a6>] ext4_direct_IO+0xd45/0x29b0 fs/ext4/inode.c:3660
 [<00000000ff96fbcc>] generic_file_direct_write+0x293/0x520 mm/filemap.c:2841
 [<00000000b796cf97>] __generic_file_write_iter+0x20f/0x530 mm/filemap.c:3021
 [<0000000060012560>] ext4_file_write_iter+0x364/0xcd0 fs/ext4/file.c:165
 [<000000002ca38818>] vfs_iter_write+0x2e2/0x580 fs/read_write.c:390
 [<000000009d16373a>] iter_file_splice_write+0x5a9/0xb10 fs/splice.c:768
 [<00000000b6c469ef>] do_splice_from fs/splice.c:870 [inline]
 [<00000000b6c469ef>] direct_splice_actor+0x126/0x1a0 fs/splice.c:1037
 [<000000009834d678>] splice_direct_to_actor+0x2c8/0x820 fs/splice.c:992
 [<00000000f2c9de3f>] do_splice_direct+0x1a5/0x260 fs/splice.c:1080
 [<000000008ac5e979>] do_sendfile+0x503/0xc00 fs/read_write.c:1402
 [<0000000060d04641>] SYSC_sendfile64 fs/read_write.c:1457 [inline]
 [<0000000060d04641>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1449
 [<0000000096824977>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<00000000f2906f0d>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Kernel Offset: disabled
Rebooting in 86400 seconds..