Re: [PATCH] fstests: btrfs: Test fiemap ioctl on completely deduped file

Christoph Hellwig
2016-05-11T05:25:47Z

On Tue, May 10, 2016 at 04:39:41PM +0800, Qu Wenruo wrote:
> For a completely deduped file, which means all its file extent are
> pointing to one bytenr, if calling fiemap on it, btrfs will cause soft
> hang up or just takes years long.
>
> This bug can be reproduced even without any in-band or out-of-band
> dedupe, normal clone_file_range() call can create such situation.
>
> This test case will detect it.

Why is this a btrfs specific test?