On Wed, Aug 12, 2020 at 07:44:19AM +0800, Ming Lei wrote:
> 1f23816b8eb8 ("virtio_blk: add discard and write zeroes support") starts
> to support multi-range discard for virtio-blk. However, the virtio-blk
> disk may report max discard segment as 1, at least that is exactly what
> qemu is doing.
>
> So far, block layer switches to normal request merge if max discard segment
> limit is 1, and multiple bios can be merged to single segment. This way may
> cause memory corruption in virtblk_setup_discard_write_zeroes().
>
> Fix the issue by handling single max discard segment in straightforward
> way.
Looks good,
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
