On 2018/6/2 5:22, Eric Northup wrote:

On Wed, May 30, 2018 at 10:04 PM Dongjiu Geng [off-list ref] wrote:

quoted

For the migrating VMs, user space may need to know the exception

[...]

quoted

+               __u8 pad[6];
+               __u64 serror_esr;
+       } exception;
+       __u32 reserved[12];

It will be easier to re-purpose this in the future if the field is
reserved and is checked that it must be zero.  SET_VCPU_EVENTS would
return EINVAL if reserved fields get used until a later meaning is
defined for them.

Ok, thanks. I will check the reserved fields when calling SET_VCPU_EVENTS.

quoted

+};
+
 /* If you need to interpret the index values, here is the key: */
 #define KVM_REG_ARM_COPROC_MASK                0x000000000FFF0000
 #define KVM_REG_ARM_COPROC_SHIFT       16

diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 56a0260..71d3841 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c

@@ -289,6 +289,42 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
        return -EINVAL;
 }

[...]

quoted

--
2.7.4

.