Hi Binbin,
On 8/13/25 2:23 AM, Binbin Wu wrote:
On 8/12/2025 4:31 AM, Sean Christopherson wrote:
On Thu, Aug 07, 2025, Sagi Shahar wrote:
[...]
/* * TD creation/setup/finalization */ @@ -459,28 +474,35 @@ static void load_td_memory_region(struct kvm_vm *vm, if (!sparsebit_any_set(pages)) return; + if (region->region.guest_memfd != -1) + register_encrypted_memory_region(vm, region);
sparsebit_for_each_set_range(pages, i, j) { const uint64_t size_to_load = (j - i + 1) * vm->page_size; const uint64_t offset = (i - lowest_page_in_region) * vm->page_size; const uint64_t hva = hva_base + offset; const uint64_t gpa = gpa_base + offset; - void *source_addr; + void *source_addr = (void *)hva; /* * KVM_TDX_INIT_MEM_REGION ioctl cannot encrypt memory in place. * Make a copy if there's only one backing memory source. */ - source_addr = mmap(NULL, size_to_load, PROT_READ | PROT_WRITE, - MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); - TEST_ASSERT(source_addr, - "Could not allocate memory for loading memory region");
- memcpy(source_addr, (void *)hva, size_to_load); + if (region->region.guest_memfd == -1) {
Oh, here's the "if".
Is it still possible for "region->region.guest_memfd == -1" case? KVM_TDX_INIT_MEM_REGION can only work with guest memfd, right?
This is still used and supports test "KVM: selftests: TDX: Test LOG_DIRTY_PAGES flag to a non-GUEST_MEMFD memslot" found in patch #30 that was created to support the issue encountered when QEMU attaches an emulated VGA device to a TD. More details available in the fix: fbb4adadea55 ("KVM: x86: Make cpu_dirty_log_size a per-VM value")
Reinette