| Message ID | 20220408004120.1969099-3-ricarkol@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: selftests: Add aarch64/page_fault_test | expand |
Hey Ricardo, Sorry about my last email hitting your v2. I fudged my inbox filtering so v3 missed my explicit-cc inbox. Oops! On Thu, Apr 07, 2022 at 05:41:09PM -0700, Ricardo Koller wrote: > Add a library function (in-guest) This function is called from host userspace, no? > to get the GPA of the PTE of a > particular GVA. This will be used in a future commit by a test to clear > and check the AF (access flag) of a particular page. > > Signed-off-by: Ricardo Koller <ricarkol@google.com> > --- > .../selftests/kvm/include/aarch64/processor.h | 2 ++ > .../selftests/kvm/lib/aarch64/processor.c | 24 +++++++++++++++++-- > 2 files changed, 24 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h > index 8f9f46979a00..caa572d83062 100644 > --- a/tools/testing/selftests/kvm/include/aarch64/processor.h > +++ b/tools/testing/selftests/kvm/include/aarch64/processor.h > @@ -125,6 +125,8 @@ void vm_install_exception_handler(struct kvm_vm *vm, > void vm_install_sync_handler(struct kvm_vm *vm, > int vector, int ec, handler_fn handler); > > +vm_paddr_t vm_get_pte_gpa(struct kvm_vm *vm, vm_vaddr_t gva); > + > static inline void cpu_relax(void) > { > asm volatile("yield" ::: "memory"); > diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c > index 9343d82519b4..ee006d354b79 100644 > --- a/tools/testing/selftests/kvm/lib/aarch64/processor.c > +++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c > @@ -139,7 +139,7 @@ void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) > _virt_pg_map(vm, vaddr, paddr, attr_idx); > } > > -vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) > +vm_paddr_t vm_get_pte_gpa(struct kvm_vm *vm, vm_vaddr_t gva) > { > uint64_t *ptep; > > @@ -162,7 +162,7 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) > goto unmapped_gva; > /* fall through */ > case 2: > - ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pte_index(vm, gva) * 8; > + ptep = (uint64_t *)(pte_addr(vm, *ptep) + pte_index(vm, gva) * 8); this seems a bit odd. ptep is an HVA in the above cases, but really a GPA here. Also -- not your code but the baked-in assumption that the stage-1 MMU always maps at leaf page granularity might be a bit of a mess if we ever do anything more interesting inside of the guest. > if (!ptep) > goto unmapped_gva; > break; > @@ -170,6 +170,26 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) > TEST_FAIL("Page table levels must be 2, 3, or 4"); > } > > + return (vm_paddr_t)ptep; > + > +unmapped_gva: > + TEST_FAIL("No mapping for vm virtual address, gva: 0x%lx", gva); > + exit(1); Isn't this just a workaround for the fact that TEST_FAIL() doesn't have the noreturn attribute specified somewhere? > +} > + > +vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) > +{ > + uint64_t *ptep; > + vm_paddr_t ptep_gpa; > + > + ptep_gpa = vm_get_pte_gpa(vm, gva); > + if (!ptep_gpa) > + goto unmapped_gva; This branch will never be taken since vm_get_pte_gpa() will explode on its own, right? -- Thanks, Oliver
diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h index 8f9f46979a00..caa572d83062 100644 --- a/tools/testing/selftests/kvm/include/aarch64/processor.h +++ b/tools/testing/selftests/kvm/include/aarch64/processor.h @@ -125,6 +125,8 @@ void vm_install_exception_handler(struct kvm_vm *vm, void vm_install_sync_handler(struct kvm_vm *vm, int vector, int ec, handler_fn handler); +vm_paddr_t vm_get_pte_gpa(struct kvm_vm *vm, vm_vaddr_t gva); + static inline void cpu_relax(void) { asm volatile("yield" ::: "memory"); diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c index 9343d82519b4..ee006d354b79 100644 --- a/tools/testing/selftests/kvm/lib/aarch64/processor.c +++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c @@ -139,7 +139,7 @@ void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) _virt_pg_map(vm, vaddr, paddr, attr_idx); } -vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) +vm_paddr_t vm_get_pte_gpa(struct kvm_vm *vm, vm_vaddr_t gva) { uint64_t *ptep; @@ -162,7 +162,7 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) goto unmapped_gva; /* fall through */ case 2: - ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pte_index(vm, gva) * 8; + ptep = (uint64_t *)(pte_addr(vm, *ptep) + pte_index(vm, gva) * 8); if (!ptep) goto unmapped_gva; break; @@ -170,6 +170,26 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) TEST_FAIL("Page table levels must be 2, 3, or 4"); } + return (vm_paddr_t)ptep; + +unmapped_gva: + TEST_FAIL("No mapping for vm virtual address, gva: 0x%lx", gva); + exit(1); +} + +vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) +{ + uint64_t *ptep; + vm_paddr_t ptep_gpa; + + ptep_gpa = vm_get_pte_gpa(vm, gva); + if (!ptep_gpa) + goto unmapped_gva; + + ptep = addr_gpa2hva(vm, ptep_gpa); + if (!ptep) + goto unmapped_gva; + return pte_addr(vm, *ptep) + (gva & (vm->page_size - 1)); unmapped_gva:
Add a library function (in-guest) to get the GPA of the PTE of a particular GVA. This will be used in a future commit by a test to clear and check the AF (access flag) of a particular page. Signed-off-by: Ricardo Koller <ricarkol@google.com> --- .../selftests/kvm/include/aarch64/processor.h | 2 ++ .../selftests/kvm/lib/aarch64/processor.c | 24 +++++++++++++++++-- 2 files changed, 24 insertions(+), 2 deletions(-)