From d2e50389ab44acfa05e72604d701a70b234f9938 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Tue, 21 Oct 2025 07:47:24 +0000 Subject: [PATCH] KVM: selftests: Make sure vm->vpages_mapped is always up-to-date Call paths leading to __virt_pg_map() are currently: (a) virt_pg_map() -> virt_arch_pg_map() -> __virt_pg_map() (b) virt_map_level() -> __virt_pg_map() For (a), calls to virt_pg_map() from kvm_util.c make sure they update vm->vpages_mapped, but other callers do not. Move the sparsebit_set() call into virt_pg_map() to make sure all callers are captured. For (b), call sparsebit_set_num() from virt_map_level(). It's tempting to have a single the call inside __virt_pg_map(), however: - The call path in (a) is not x86-specific, while (b) is. Moving the call into __virt_pg_map() would require doing something similar for other archs implementing virt_pg_map(). - Future changes will reusue __virt_pg_map() for nested PTEs, which should not update vm->vpages_mapped, i.e. a triple underscore version that does not update vm->vpages_mapped would need to be provided. Signed-off-by: Yosry Ahmed Link: https://patch.msgid.link/20251021074736.1324328-12-yosry.ahmed@linux.dev Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/include/kvm_util.h | 1 + tools/testing/selftests/kvm/lib/kvm_util.c | 3 --- tools/testing/selftests/kvm/lib/x86/processor.c | 2 ++ 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 8a54a1279d441..d701ee557f5b9 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -1230,6 +1230,7 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr); static inline void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) { virt_arch_pg_map(vm, vaddr, paddr); + sparsebit_set(vm->vpages_mapped, vaddr >> vm->page_shift); } diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 364efd02ad4a3..33aebedfc0508 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1458,8 +1458,6 @@ static vm_vaddr_t ____vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, pages--, vaddr += vm->page_size, paddr += vm->page_size) { virt_pg_map(vm, vaddr, paddr); - - sparsebit_set(vm->vpages_mapped, vaddr >> vm->page_shift); } return vaddr_start; @@ -1573,7 +1571,6 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, while (npages--) { virt_pg_map(vm, vaddr, paddr); - sparsebit_set(vm->vpages_mapped, vaddr >> vm->page_shift); vaddr += page_size; paddr += page_size; diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c index 40bd69b265ef1..36104d27f3d9f 100644 --- a/tools/testing/selftests/kvm/lib/x86/processor.c +++ b/tools/testing/selftests/kvm/lib/x86/processor.c @@ -286,6 +286,8 @@ void virt_map_level(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, for (i = 0; i < nr_pages; i++) { __virt_pg_map(vm, vaddr, paddr, level); + sparsebit_set_num(vm->vpages_mapped, vaddr >> vm->page_shift, + nr_bytes / PAGE_SIZE); vaddr += pg_size; paddr += pg_size; -- 2.47.3