linux-kernel - Re: [PATCH v3 0/4] KVM: arm64: Add attribute to control GICD

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aEyPswyvfJ2-oC3l@linux.dev>
Date: Fri, 13 Jun 2025 13:53:07 -0700
From: Oliver Upton <oliver.upton@...ux.dev>
To: Raghavendra Rao Ananta <rananta@...gle.com>
Cc: Marc Zyngier <maz@...nel.org>, Mingwei Zhang <mizhang@...gle.com>,
	linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [PATCH v3 0/4] KVM: arm64: Add attribute to control
 GICD_TYPER2.nASSGIcap

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.

Thanks,
Oliver