On 06-Aug-18 10:50 AM, Thomas Monjalon wrote:

06/08/2018 10:43, Takeshi Yoshimura:

quoted

Commit 73a639085938 ("vfio: allow to map other memory regions")
introduced a bug in sPAPR IOMMU mapping. The commit removed necessary
ioctl with VFIO_IOMMU_SPAPR_REGISTER_MEMORY. Also, vfio_spapr_map_walk
should call vfio_spapr_dma_do_map instead of vfio_spapr_dma_mem_map.

This is fixing an old patch:
	http://git.dpdk.org/dpdk/commit/?id=73a639085938

quoted

Fixes: 73a639085938 ("vfio: allow to map other memory regions")

You probably want it to be backported in previous release,
so you need to add Cc: stable@dpdk.org

quoted

Signed-off-by: Takeshi Yoshimura <redacted>

It is common to have bugs in sPAPR implementation.
How can we be sure this one is OK?
Should it be added in last minute of 18.08?
Or can it wait 18.11?

Adding Anatoly and Chao who are maintainers to decide.

The patch appears to be correct - we did have a 
VFIO_IOMMU_SPAPR_REGISTER_MEMORY ioctl in the old map() function, but 
not in the new one.

However, i agree with Thomas - without more testing from other sPAPR 
users/IBM, i would be hesitant to allow it in at the last minute. In any 
case, this code has been there for a while and no one has reported any 
issues - so this can probably wait until 18.11, seeing how this codepath 
is so popular :)

-- 
Thanks,
Anatoly