[PATCH 1/3] KVM: arm64: Make ID_PFR1_EL1.GIC writable

Oliver Upton oliver.upton at linux.dev
Wed Oct 22 00:00:47 PDT 2025


Hey,

On Mon, Oct 13, 2025 at 09:32:05AM +0100, Marc Zyngier wrote:
> Similarly to ID_AA64PFR0_EL1.GIC, relax ID_PFR1_EL1.GIC to be writable.

This looks fine to me, although I do wonder if we should just allow
userspace to write whatever value it wants to the 32-bit ID registers
and be done with it.

Nowhere do we use a 32-bit ID register value as a condition for trap
configuration / emulation, so even if the VMM lies to the guest it
shouldn't trip up KVM.

Thanks,
Oliver



More information about the linux-arm-kernel mailing list