On 2/14/25 2:14 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 c785005f821f..4f7602aa3c6c 100644
--- a/arch/arm64/kvm/rme-exit.c
+++ b/arch/arm64/kvm/rme-exit.c
@@ -107,6 +107,26 @@ static int rec_exit_ripas_change(struct kvm_vcpu *vcpu)
return -EFAULT;
}
+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;
+}
+
I don't understand how a negative error can be returned from kvm_smccc_call_handler().
Besides, SMCCC_RET_NOT_SUPPORTED has been set to GPR[0 - 3] if the request can't be
supported. Why we need to set GPR[0] to ~0UL, which corresponds to SMCCC_RET_NOT_SUPPORTED
if I'm correct. I guess change log or a comment to explain the questions would be
nice.
static void update_arch_timer_irq_lines(struct kvm_vcpu *vcpu)
{
struct realm_rec *rec = &vcpu->arch.rec;
@@ -168,6 +188,8 @@ 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
