[v6] HVF: Add support for platform vGIC and nested virtualisation

[PATCH v6 13/13] target/arm: hvf: add asserts for code paths not leveraged when using the vGIC

Posted by Mohamed Mediouni 4 months, 1 week ago

When using the vGIC, timers are directly handled by the platform.
No vmexits ought to happen in that case. Abort if reaching those code paths.

Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
---
 target/arm/hvf/hvf.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c
index bb7b84ff35..1d285c70d8 100644
--- a/target/arm/hvf/hvf.c
+++ b/target/arm/hvf/hvf.c
@@ -1477,6 +1477,7 @@ static int hvf_sysreg_read(CPUState *cpu, uint32_t reg, uint64_t *val)
     case SYSREG_ICC_SGI1R_EL1:
     case SYSREG_ICC_SRE_EL1:
     case SYSREG_ICC_CTLR_EL1:
+        assert(!hvf_irqchip_in_kernel());
         /* Call the TCG sysreg handler. This is only safe for GICv3 regs. */
         if (hvf_sysreg_read_cp(cpu, reg, val)) {
             return 0;
@@ -1803,6 +1804,7 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val)
     case SYSREG_ICC_SGI0R_EL1:
     case SYSREG_ICC_SGI1R_EL1:
     case SYSREG_ICC_SRE_EL1:
+        assert(!hvf_irqchip_in_kernel());
         /* Call the TCG sysreg handler. This is only safe for GICv3 regs. */
         if (hvf_sysreg_write_cp(cpu, reg, val)) {
             return 0;
@@ -2066,6 +2068,7 @@ int hvf_vcpu_exec(CPUState *cpu)
         /* This is the main one, handle below. */
         break;
     case HV_EXIT_REASON_VTIMER_ACTIVATED:
+        assert(!hvf_irqchip_in_kernel());
         qemu_set_irq(arm_cpu->gt_timer_outputs[GTIMER_VIRT], 1);
         cpu->accel->vtimer_masked = true;
         return 0;
-- 
2.39.5 (Apple Git-154)

Re: [PATCH v6 13/13] target/arm: hvf: add asserts for code paths not leveraged when using the vGIC

Posted by Mads Ynddal 3 months, 3 weeks ago

> On 8 Aug 2025, at 09.01, Mohamed Mediouni <mohamed@unpredictable.fr> wrote:
> 
> When using the vGIC, timers are directly handled by the platform.
> No vmexits ought to happen in that case. Abort if reaching those code paths.
> 
> Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
> ---
> target/arm/hvf/hvf.c | 3 +++
> 1 file changed, 3 insertions(+)

Makes good sense to verify this.

Reviewed-by: Mads Ynddal <mads@ynddal.dk>