AArch64 EL2 hypervisor for QEMU virt that boots at EL2
Normalise readonly device emulation semantics across probe paths
author
vm.fail
date
(May 18, 2026, 7:12 PM UTC)
commit
0061aeee
0061aeeea62c58e51bb36e0e522f1e1e1f638315
parent
a8b8f2ca
a8b8f2caad5e67fadfd0b989ada99fb3b7f148f8
vm.fail
date
(May 18, 2026, 7:12 PM UTC)
commit
0061aeee
0061aeeea62c58e51bb36e0e522f1e1e1f638315
parent
a8b8f2ca
a8b8f2caad5e67fadfd0b989ada99fb3b7f148f8
+10
-3
+10
-3
core/mmio_policy.c
+10
-3
core/mmio_policy.c
···
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return (uint64_t)mmio_read32((uintptr_t)ipa);
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}
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+
static bool emulate_readonly_probe(struct vcpu *vcpu, ipa_t ipa, bool is_write, uint32_t rt)
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{
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if (is_write) {
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return true;
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}
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vcpu_write_gpr(vcpu, rt, readonly_device_read32(ipa));
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return true;
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}
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+
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bool mmio_policy_emulate(struct vcpu *vcpu, ipa_t ipa, uint64_t esr_el2)
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{
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const struct mmio_policy_region *region = mmio_policy_lookup(ipa);
···
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value = virtio_read(off);
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}
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} else if (region->action == MMIO_POLICY_EMULATE_READONLY_DEVICE) {
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-
if (!is_write) {
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-
value = readonly_device_read32(ipa);
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-
}
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+
return emulate_readonly_probe(vcpu, ipa, is_write, rt);
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} else if (region->action != MMIO_POLICY_EMULATE_ZERO) {
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return false;
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}