[0/2] s390x/pci: small set of fixes

Message

Matthew Rosato Nov. 9, 2023, 10:53 p.m. UTC

The following set of changes are associated with issues exposed by testing
of the 'vfio: Adopt iommufd' series.

The first patch fixes an existing assumption that a vfio device will always
have a group fd (which is no longer true if cdev is used, which can only
happen once the iommufd backend is used).  This patch really only needs to
go into 8.2 if the 'vfio: Adopt iommufd' series does (but would be fine to 
go into 8.2 without it too).

The second patch fixes an issue where we do not detect that a vfio DMA limit
was never read from vfio.  This is actually an existing bug as it's possible
for an older host kernel to be missing this support today; so ideally this one
should be targeted for 8.2 regardless. 

Matthew Rosato (2):
  s390x/pci: bypass vfio DMA counting when using cdev
  s390x/pci: only limit DMA aperture if vfio DMA limit reported

 hw/s390x/s390-pci-vfio.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

Comments

Cédric Le Goater Nov. 10, 2023, 7:40 a.m. UTC | #1

Hello Matthew,

On 11/9/23 23:53, Matthew Rosato wrote:
> The following set of changes are associated with issues exposed by testing
> of the 'vfio: Adopt iommufd' series.
> 
> The first patch fixes an existing assumption that a vfio device will always
> have a group fd (which is no longer true if cdev is used, which can only
> happen once the iommufd backend is used).  This patch really only needs to
> go into 8.2 if the 'vfio: Adopt iommufd' series does (but would be fine to
> go into 8.2 without it too).

It is a bit late for the 8.2. So we have time to polish v5 of the 'vfio: Adopt
iommufd' series a bit more. I should include the v6 in an early PR for a 9.0.
  
> The second patch fixes an issue where we do not detect that a vfio DMA limit
> was never read from vfio.  This is actually an existing bug as it's possible
> for an older host kernel to be missing this support today; so ideally this one
> should be targeted for 8.2 regardless.

Nevertheless, I hope these two fixes can reached 8.2 since they are good
to have anyhow.

Thanks,

C.

  
> Matthew Rosato (2):
>    s390x/pci: bypass vfio DMA counting when using cdev
>    s390x/pci: only limit DMA aperture if vfio DMA limit reported
> 
>   hw/s390x/s390-pci-vfio.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
>