On Thu, Sep 14, 2017 at 02:31:13PM +0100, Alex Benn?e wrote:

Dave Martin [off-list ref] writes:

quoted

When trapping forbidden attempts by a guest to use SVE, we want the
guest to see a trap consistent with SVE not being implemented.

This patch injects an undefined instruction exception into the
guest in response to such an exception.

I do wonder if this should be merged with the previous trap enabling
patch though?

Yes, that would make sense now I look at it.

Can I keep your Reviewed-by on the combined patch?

Cheers
---Dave

quoted

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
---
 arch/arm64/kvm/handle_exit.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 17d8a16..e3e42d0 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c

@@ -147,6 +147,13 @@ static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	return 1;
 }

+static int handle_sve(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	/* Until SVE is supported for guests: */
+	kvm_inject_undefined(vcpu);
+	return 1;
+}
+
 static exit_handle_fn arm_exit_handlers[] = {
 	[0 ... ESR_ELx_EC_MAX]	= kvm_handle_unknown_ec,
 	[ESR_ELx_EC_WFx]	= kvm_handle_wfx,

@@ -160,6 +167,7 @@ static exit_handle_fn arm_exit_handlers[] = {
 	[ESR_ELx_EC_HVC64]	= handle_hvc,
 	[ESR_ELx_EC_SMC64]	= handle_smc,
 	[ESR_ELx_EC_SYS64]	= kvm_handle_sys_reg,
+	[ESR_ELx_EC_SVE]	= handle_sve,
 	[ESR_ELx_EC_IABT_LOW]	= kvm_handle_guest_abort,
 	[ESR_ELx_EC_DABT_LOW]	= kvm_handle_guest_abort,
 	[ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug,

--
Alex Benn?e

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