On 12/13/24 1:55 AM, Steven Price wrote:
From: Joey Gouly <joey.gouly@xxxxxxx>
Forward RSI_HOST_CALLS to KVM's HVC handler.
Signed-off-by: Joey Gouly <joey.gouly@xxxxxxx>
Signed-off-by: Steven Price <steven.price@xxxxxxx>
---
Changes since v4:
* Setting GPRS is now done by kvm_rec_enter() rather than
rec_exit_host_call() (see previous patch - arm64: RME: Handle realm
enter/exit). This fixes a bug where the registers set by user space
were being ignored.
---
arch/arm64/kvm/rme-exit.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/arch/arm64/kvm/rme-exit.c b/arch/arm64/kvm/rme-exit.c
index 8f0f9ab57f28..b2a367474d74 100644
--- a/arch/arm64/kvm/rme-exit.c
+++ b/arch/arm64/kvm/rme-exit.c
@@ -103,6 +103,26 @@ static int rec_exit_ripas_change(struct kvm_vcpu *vcpu)
return 0;
}
+static int rec_exit_host_call(struct kvm_vcpu *vcpu)
+{
+ int ret, i;
+ struct realm_rec *rec = &vcpu->arch.rec;
+
+ vcpu->stat.hvc_exit_stat++;
+
+ for (i = 0; i < REC_RUN_GPRS; i++)
+ vcpu_set_reg(vcpu, i, rec->run->exit.gprs[i]);
+
+ ret = kvm_smccc_call_handler(vcpu);
+
+ if (ret < 0) {
+ vcpu_set_reg(vcpu, 0, ~0UL);
+ ret = 1;
+ }
+
+ return ret;
+}
+
It seems that the return value from kvm_smccc_call() won't be negative. Besides,
the host call requests are currently handled by kvm_psci_call(), which isn't
what we want. So I think a new helper is needed and called in kvm_smccc_call_handler().
The new helper simply push the error (NOT_SUPPORTED) to x0. Otherwise, a unexpected
return value will be seen by guest.
handle_rec_exit
rec_exit_host_call
kvm_smccc_call_handler
static void update_arch_timer_irq_lines(struct kvm_vcpu *vcpu)
{
struct realm_rec *rec = &vcpu->arch.rec;
@@ -164,6 +184,8 @@ int handle_rec_exit(struct kvm_vcpu *vcpu, int rec_run_ret)
return rec_exit_psci(vcpu);
case RMI_EXIT_RIPAS_CHANGE:
return rec_exit_ripas_change(vcpu);
+ case RMI_EXIT_HOST_CALL:
+ return rec_exit_host_call(vcpu);
}
kvm_pr_unimpl("Unsupported exit reason: %u\n",
Thanks,
Gavin
