Re: [PATCH] virtio_blk: avoid DMA to stack for the sense buffer

[Christoph Hellwig]

On Wed, Jan 04, 2017 at 04:47:03PM +0100, çéæ wrote:
> This sounds scary.
> Could you share how to reproduce it, this should go into stable if
> it's the case.

Step 1: Build your kernel with CONFIG_VMAP_STACK=y
Step 2: issue a SG_IO ioctl, e.g. sg_inq /dev/vda