KVM: selftests: aarch64: Add aarch64/page_fault_test

Add a new test for stage 2 faults when using different combinations of
guest accesses (e.g., write, S1PTW), backing source type (e.g., anon)
and types of faults (e.g., read on hugetlbfs with a hole). The next
commits will add different handling methods and more faults (e.g., uffd
and dirty logging). This first commit starts by adding two sanity checks
for all types of accesses: AF setting by the hw, and accessing memslots
with holes.

Signed-off-by: Ricardo Koller <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: Ricardo Koller

tools/testing/selftests/kvm/.gitignore

@@ -4,6 +4,7 @@
 /aarch64/debug-exceptions
 /aarch64/get-reg-list
 /aarch64/hypercalls
+/aarch64/page_fault_test
 /aarch64/psci_test
 /aarch64/vcpu_width_config
 /aarch64/vgic_init

tools/testing/selftests/kvm/Makefile

@@ -153,6 +153,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
 TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
 TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
 TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
+TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
 TEST_GEN_PROGS_aarch64 += aarch64/psci_test
 TEST_GEN_PROGS_aarch64 += aarch64/vcpu_width_config
 TEST_GEN_PROGS_aarch64 += aarch64/vgic_init