Dave Martin <dave.mar...@arm.com> writes: > The Arm SVE architecture defines registers that are up to 2048 bits > in size (with some possibility of further future expansion). > > In order to avoid the need for an excessively large number of > ioctls when saving and restoring a vcpu's registers, this patch > adds a #define to make support for individual 2048-bit registers > through the KVM_{GET,SET}_ONE_REG ioctl interface official. This > will allow each SVE register to be accessed in a single call. > > There are sufficient spare bits in the register id size field for > this change, so there is no ABI impact providing that > KVM_GET_REG_LIST does not enumerate any 2048-bit register unless > userspace explicitly opts in to the relevant architecture-specific > features. > > Signed-off-by: Dave Martin <dave.mar...@arm.com> > --- > include/uapi/linux/kvm.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 251be35..7c3c5cc 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -1110,6 +1110,7 @@ struct kvm_dirty_tlb { > #define KVM_REG_SIZE_U256 0x0050000000000000ULL > #define KVM_REG_SIZE_U512 0x0060000000000000ULL > #define KVM_REG_SIZE_U1024 0x0070000000000000ULL > +#define KVM_REG_SIZE_U2048 0x0080000000000000ULL
Yeah OK I guess - but it does make me question if KVM_REG_SIZE_MASK is part of the ABI because although we have space for another few bits that is the last one without changing the mask. Reviewed-by: Alex Bennée <alex.ben...@linaro.org> > > struct kvm_reg_list { > __u64 n; /* number of regs */ -- Alex Bennée _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm