Re: [PATCH v4 0/2] pci: slot_reserved_mask improvements

[Mark Cave-Ayland]

On 15/03/2023 14:26, Chuck Zmudzinski wrote:

> This patch series consists of two patches. The first provides accessor
> functions in pci.h to avoid direct access of slot_reserved_mask
> according to the comment at the top of include/hw/pci/pci_bus.h. No
> functional change is intended with this patch.
>
> The second patch replaces slot_reserved_mask with two new masks,
> slot_reserved_auto_mask and slot_reserved_manual_mask so the current
> behavior of reserving slot 2 for the Intel IGD for the xenfv machine
> will be ignored if an administrator manually configures a device to use
> the reserved slot.
>
> The current behavior of always reserving slots in the sun4u machine is
> preserved by this patch series; the patch series only changes how
> slot_reserved_mask works in the xenfv machine. Although the patch
> series can affect xenfv machines configured for igd-passthru if an
> administrator assigns some of the pci slot addresses manually, it
> does not affect the libxl default configuration for igd-passthru because
> libxl uses automatic slot assignment by default.
>
> Testing:
>     - Tested xenfv/igd with both manual and auto slot allocation - behaves as 
> expected
>     - Verified that qemu-system-sparc64 still compiles with the patches to 
> sun4u.c
>     - xen4u machine not tested -- Mark, can you do this?
>
> Link: 
> https://lore.kernel.org/qemu-devel/20230106064838-mutt-send-email-mst@kernel.org/
>
> Chuck Zmudzinski (2):
>    pci: avoid accessing slot_reserved_mask directly outside of pci.c
>    pci: introduce slot_reserved_auto_mask and slot_reserved_manual_mask
>
> Changelog
>
> v4: I forgot to check the patches in v3 for style corrections (sorry about
>      that), and the second patch had three lines that were too long. Other
>      than correcting the style problems, no changes since v3.
>
> v3: Re-work second patch in response to comments/discussion of v2
>
> v2: Add first patch and cover letter to make this a 2-patch series
>      Make changes to the second patch (see second patch for changelog)
>
>   hw/pci/pci.c             | 33 ++++++++++++++++++++++++++++-----
>   hw/sparc64/sun4u.c       |  7 +++----
>   hw/xen/xen_pt.c          |  8 ++++----
>   include/hw/pci/pci.h     |  3 +++
>   include/hw/pci/pci_bus.h |  3 ++-
>   5 files changed, 40 insertions(+), 14 deletions(-)

The v4 series looks good to me: I've also confirmed that sun4u still works as before, 
so from my perspective:

Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> [sun4u]

Michael, is this a candidate for 8.0 given that the existing patches for Xen making 
use of slot_reserved_mask have already been merged?


ATB,

Mark.