Fix default scrambling of buffers

Commit 1bf2498d3111 inadvertently made us not scramble by default.
The logic was a bit convoluted, so clear it up and scramble if:

- Asked so by adding scramble_buffers=1
- Or, if not asked to explicitly, but zero_buffers not set to 1.

Reported-by: Chris Wilson <>
Signed-off-by: Jens Axboe <>
1 file changed