| Message ID | 20220921152436.3673454-30-vkuznets@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features | expand |
On Wed, Sep 21, 2022, Vitaly Kuznetsov wrote: > Make it possible for tests to mangle guest's page table entries in > addition to just getting them (available with vm_get_page_table_entry()). > > Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> > --- > tools/testing/selftests/kvm/include/x86_64/processor.h | 2 ++ > tools/testing/selftests/kvm/lib/x86_64/processor.c | 5 ++--- > 2 files changed, 4 insertions(+), 3 deletions(-) > > diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h > index 1c7805de8c27..500d711eb989 100644 > --- a/tools/testing/selftests/kvm/include/x86_64/processor.h > +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h > @@ -827,6 +827,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val) > return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr)); > } > > +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, > + uint64_t vaddr); > uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, > uint64_t vaddr); > void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, > diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c > index 2e6e61bbe81b..5c135f896ada 100644 > --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c > +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c > @@ -214,9 +214,8 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) > __virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K); > } > > -static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, > - struct kvm_vcpu *vcpu, > - uint64_t vaddr) > +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, > + uint64_t vaddr) Ugh, obviously not your fault, but this is a terrible name. Aside from using a single underscore, it's semantically very different than vm_get_page_table_entry(), i.e. violates the stand "double underscores is an inner helper". The innards of vm_{g,s}et_page_table_entry() are quite hilarious too as they cast a "uint64_t *" to "uint64_t*" now that KVM no longer uses structs to manage PTEs (commit f18b4aebe107 ("kvm: selftests: do not use bitfields larger than 32-bits for PTEs")). And looking at the sole usage in emulator_error_test.c, provide get+set helpers is silly. Rather than expose this weirdness, what about slotting in the below to drop the wrappers and just let tests modify PTEs directly? --- From: Sean Christopherson <seanjc@google.com> Date: Wed, 21 Sep 2022 15:08:49 -0700 Subject: [PATCH] KVM: selftests: Drop helpers to read/write page table entries Drop vm_{g,s}et_page_table_entry() and instead expose the "inner" helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the PTE, i.e. let tests directly modify PTEs instead of bouncing through helpers that just make life difficult. Opportunsitically use BIT_ULL() in emulator_error_test, and use the MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the same value. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> --- .../selftests/kvm/include/x86_64/processor.h | 6 ++---- .../selftests/kvm/lib/x86_64/processor.c | 21 ++----------------- .../kvm/x86_64/emulator_error_test.c | 6 ++++-- 3 files changed, 8 insertions(+), 25 deletions(-) diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 0cbc71b7af50..5999e974a150 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -825,10 +825,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val) return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr)); } -uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, - uint64_t vaddr); -void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, - uint64_t vaddr, uint64_t pte); +uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, + uint64_t vaddr); uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2, uint64_t a3); diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 2e6e61bbe81b..5e4bbe71dbff 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -214,9 +214,8 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) __virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K); } -static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, - struct kvm_vcpu *vcpu, - uint64_t vaddr) +uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, + uint64_t vaddr) { uint16_t index[4]; uint64_t *pml4e, *pdpe, *pde; @@ -286,22 +285,6 @@ static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, return &pte[index[0]]; } -uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, - uint64_t vaddr) -{ - uint64_t *pte = _vm_get_page_table_entry(vm, vcpu, vaddr); - - return *(uint64_t *)pte; -} - -void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, - uint64_t vaddr, uint64_t pte) -{ - uint64_t *new_pte = _vm_get_page_table_entry(vm, vcpu, vaddr); - - *(uint64_t *)new_pte = pte; -} - void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent) { uint64_t *pml4e, *pml4e_start; diff --git a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c index 236e11755ba6..bde247f3c8a1 100644 --- a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c +++ b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c @@ -152,8 +152,9 @@ int main(int argc, char *argv[]) { struct kvm_vcpu *vcpu; struct kvm_vm *vm; - uint64_t gpa, pte; + uint64_t *pte; uint64_t *hva; + uint64_t gpa; int rc; /* Tell stdout not to buffer its content */ @@ -178,8 +179,9 @@ int main(int argc, char *argv[]) virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1); hva = addr_gpa2hva(vm, MEM_REGION_GPA); memset(hva, 0, PAGE_SIZE); + pte = vm_get_page_table_entry(vm, vcpu, MEM_REGION_GVA); - vm_set_page_table_entry(vm, vcpu, MEM_REGION_GVA, pte | (1ull << 36)); + *pte |= BIT_ULL(MAXPHYADDR); vcpu_run(vcpu); process_exit_on_emulation_error(vcpu); base-commit: 3b69d246e2f1eef553508c79f5d3b2dfc4978bc1 --
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 1c7805de8c27..500d711eb989 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -827,6 +827,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val) return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr)); } +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, + uint64_t vaddr); uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, uint64_t vaddr); void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 2e6e61bbe81b..5c135f896ada 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -214,9 +214,8 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) __virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K); } -static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, - struct kvm_vcpu *vcpu, - uint64_t vaddr) +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu, + uint64_t vaddr) { uint16_t index[4]; uint64_t *pml4e, *pdpe, *pde;
Make it possible for tests to mangle guest's page table entries in addition to just getting them (available with vm_get_page_table_entry()). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- tools/testing/selftests/kvm/include/x86_64/processor.h | 2 ++ tools/testing/selftests/kvm/lib/x86_64/processor.c | 5 ++--- 2 files changed, 4 insertions(+), 3 deletions(-)