On 9/4/26 5:36 AM, Mathieu Poirier wrote:
From: Jean-Philippe Brucker <[email protected]>
When RME is enabled, the upper GPA bit is used to distinguish protected
from unprotected addresses. Reserve it when setting up the guest memory
map.
Signed-off-by: Jean-Philippe Brucker <[email protected]>
Signed-off-by: Mathieu Poirier <[email protected]>
---
hw/arm/virt.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 61751aa31e0d..cf3a9320dc3a 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -4054,17 +4054,27 @@ static int virt_kvm_type(MachineState *ms, const char
*type_str)
{
VirtMachineState *vms = VIRT_MACHINE(ms);
int max_vm_pa_size, requested_pa_size;
+ int rme_reserve_bit = 0;
bool fixed_ipa;
int vm_type;
- max_vm_pa_size = kvm_arm_get_max_vm_ipa_size(ms, &fixed_ipa);
-
vm_type = (ms->cgs ? KVM_VM_TYPE_ARM_REALM : KVM_VM_TYPE_ARM_NORMAL);
+ if (vm_type) {
+ /*
+ * With RME, the upper GPA bit differentiates Realm from NS memory.
+ * Reserve the upper bit to ensure that highmem devices will fit.
+ */
+ rme_reserve_bit = 1;
+ }
"if (vm_type)" are mapped to any VM types other than KVM_VM_TYPE_ARM_NORMAL,
meaning
it can be PKVM in theory. So this would be:
if (vm_type == KVM_VM_TYPE_ARM_REALM) {
...
}
+
+ max_vm_pa_size = kvm_arm_get_max_vm_ipa_size(ms, &fixed_ipa) -
+ rme_reserve_bit;
+
/* we freeze the memory map to compute the highest gpa */
virt_set_memmap(vms, max_vm_pa_size);
- requested_pa_size = 64 - clz64(vms->highest_gpa);
+ requested_pa_size = 64 - clz64(vms->highest_gpa) + rme_reserve_bit;
/*
* KVM requires the IPA size to be at least 32 bits.
@@ -4073,11 +4083,11 @@ static int virt_kvm_type(MachineState *ms, const char
*type_str)
requested_pa_size = 32;
}
- if (requested_pa_size > max_vm_pa_size) {
+ if (requested_pa_size > max_vm_pa_size + rme_reserve_bit) {
error_report("-m and ,maxmem option values "
"require an IPA range (%d bits) larger than "
"the one supported by the host (%d bits)",
- requested_pa_size, max_vm_pa_size);
+ requested_pa_size, max_vm_pa_size + rme_reserve_bit);
return -1;
}
/*
Thanks,
Gavin
