Plumb the MMIO checking code into the MMIO fault handling code.
Nothing allows a region to be registered yet, so there should be
no funtional change either.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kvm/mmio.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c
index 3dd38a151d2a..dfa375823264 100644
--- a/arch/arm64/kvm/mmio.c
+++ b/arch/arm64/kvm/mmio.c
@@ -6,6 +6,7 @@
#include <linux/kvm_host.h>
#include <asm/kvm_emulate.h>
+#include <asm/kvm_mmu.h>
#include <trace/events/kvm.h>
#include "trace.h"
@@ -135,6 +136,13 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
* volunteered to do so, and bail out otherwise.
*/
if (!kvm_vcpu_dabt_isvalid(vcpu)) {
+ /* With MMIO guard enabled, the guest should know better */
+ if (test_bit(KVM_ARCH_FLAG_MMIO_GUARD,
+ &vcpu->kvm->arch.flags)) {
+ kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
+ return 1;
+ }
+
if (test_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
&vcpu->kvm->arch.flags)) {
run->exit_reason = KVM_EXIT_ARM_NISV;
@@ -156,6 +164,15 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
len = kvm_vcpu_dabt_get_as(vcpu);
rt = kvm_vcpu_dabt_get_rd(vcpu);
+ /* Check failed? Return to the guest for debriefing... */
+ if (!kvm_check_ioguard_page(vcpu, fault_ipa))
+ return 1;
+
+ /* If we cross a page boundary, check that too... */
+ if (((fault_ipa + len - 1) & PAGE_MASK) != (fault_ipa & PAGE_MASK) &&
+ !kvm_check_ioguard_page(vcpu, fault_ipa + len - 1))
+ return 1;
+
if (is_write) {
data = vcpu_data_guest_to_host(vcpu, vcpu_get_reg(vcpu, rt),
len);
--
2.30.2
