Re: [PATCH v3 0/4] KVM: arm64: Add attribute to control GICD_TYPER2.nASSGIcap

Raghavendra Rao Ananta
2025-06-13T21:25:39Z

On Fri, Jun 13, 2025 at 1:53 PM Oliver Upton <oliver.upton@linux.dev> wrote:
>
> On Fri, Jun 13, 2025 at 03:52:34PM +0000, Raghavendra Rao Ananta wrote:
> > A shortcoming of the GIC architecture is that there's an absolute limit on
> > the number of vPEs that can be tracked by the ITS. It is possible that
> > an operator is running a mix of VMs on a system, only wanting to provide
> > a specific class of VMs with hardware interrupt injection support.
> >
> > The series introduces KVM_DEV_ARM_VGIC_FEATURE_nASSGIcap vGIC attribute to allow
> > the userspace to control GICD_TYPER2.nASSGIcap (GICv4.1) on a per-VM basis.
> >
> > v1: https://lore.kernel.org/kvmarm/20250514192159.1751538-1-rananta@google.com/
> >
> > v1 -> v2: https://lore.kernel.org/all/20250531012545.709887-1-oliver.upton@linux.dev/
> > - Drop all use of GICv4 in the UAPI and KVM-internal helpers in favor
> > of nASSGIcap. This changes things around to model a guest feature,
> > not a host feature.
> >
> > - Consolidate UAPI into a single attribute and expect userspace to use
> > to read the attribute for discovery, much like we do with the ID
> > registers
> >
> > - Squash documentation together with implementation
> >
> > - Clean up maintenance IRQ attribute handling, which I ran into as part
> > of reviewing this series
> >
> > v2 -> v3:
> > - Update checks in vgic-v3.c and vgic-v4.c to also include nASSGIcap (via
> > vgic_supports_direct_sgis()) that's configured by the userspace. (Oliver)
> >
> > Oliver Upton (2):
> > KVM: arm64: Disambiguate support for vSGIs v. vLPIs
> > KVM: arm64: vgic-v3: Consolidate MAINT_IRQ handling
>
> Make sure you run checkpatch next time before sending out, it should've
> warned you about sending patches w/o including your SOB.
>
Hmm, I do run checkpatch before sending, but I don't see any warning as such.

Example:
$ ./scripts/checkpatch.pl
v3-0001-KVM-arm64-Disambiguate-support-for-vSGIs-v.-vLPIs.patch
total: 0 errors, 0 warnings, 107 lines checked

v3-0001-KVM-arm64-Disambiguate-support-for-vSGIs-v.-vLPIs.patch has no
obvious style problems and is ready for submission.

I do see an option to tell the script to ignore the check:
--no-signoff, so I'm guessing it should check by default? Or is there
any other option?

Thank you.
Raghavendra