[PATCH 14/18] KVM: selftests: Fold x86's descriptor tables helpers into vcpu_init_sregs()

From: Sean Christopherson
Date: Thu Mar 14 2024 - 19:35:39 EST


Now that the per-VM, on-demand allocation logic in kvm_setup_gdt() and
vcpu_init_descriptor_tables() is gone, fold them into vcpu_init_sregs().

Note, both kvm_setup_gdt() and vcpu_init_descriptor_tables() configured the
GDT, which is why it looks like kvm_setup_gdt() disappears.

Opportunistically delete the pointless zeroing of the IDT limit (it was
being unconditionally overwritten by vcpu_init_descriptor_tables()).

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/lib/x86_64/processor.c | 32 ++++---------------
1 file changed, 6 insertions(+), 26 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 561c0aa93608..5cf845975f66 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -516,12 +516,6 @@ vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
return vm_untag_gpa(vm, PTE_GET_PA(*pte)) | (gva & ~HUGEPAGE_MASK(level));
}

-static void kvm_setup_gdt(struct kvm_vm *vm, struct kvm_dtable *dt)
-{
- dt->base = vm->arch.gdt;
- dt->limit = getpagesize() - 1;
-}
-
static void kvm_setup_tss_64bit(struct kvm_vm *vm, struct kvm_segment *segp,
int selector)
{
@@ -537,32 +531,19 @@ static void kvm_setup_tss_64bit(struct kvm_vm *vm, struct kvm_segment *segp,
kvm_seg_fill_gdt_64bit(vm, segp);
}

-static void vcpu_init_descriptor_tables(struct kvm_vcpu *vcpu)
+static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
{
- struct kvm_vm *vm = vcpu->vm;
struct kvm_sregs sregs;

+ TEST_ASSERT_EQ(vm->mode, VM_MODE_PXXV48_4K);
+
+ /* Set mode specific system register values. */
vcpu_sregs_get(vcpu, &sregs);
+
sregs.idt.base = vm->arch.idt;
sregs.idt.limit = NUM_INTERRUPTS * sizeof(struct idt_entry) - 1;
sregs.gdt.base = vm->arch.gdt;
sregs.gdt.limit = getpagesize() - 1;
- kvm_seg_set_kernel_data_64bit(NULL, DEFAULT_DATA_SELECTOR, &sregs.gs);
- vcpu_sregs_set(vcpu, &sregs);
-}
-
-static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
-{
- struct kvm_sregs sregs;
-
- TEST_ASSERT_EQ(vm->mode, VM_MODE_PXXV48_4K);
-
- /* Set mode specific system register values. */
- vcpu_sregs_get(vcpu, &sregs);
-
- sregs.idt.limit = 0;
-
- kvm_setup_gdt(vm, &sregs.gdt);

sregs.cr0 = X86_CR0_PE | X86_CR0_NE | X86_CR0_PG;
sregs.cr4 |= X86_CR4_PAE | X86_CR4_OSFXSR;
@@ -572,12 +553,11 @@ static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
kvm_seg_set_kernel_code_64bit(vm, DEFAULT_CODE_SELECTOR, &sregs.cs);
kvm_seg_set_kernel_data_64bit(vm, DEFAULT_DATA_SELECTOR, &sregs.ds);
kvm_seg_set_kernel_data_64bit(vm, DEFAULT_DATA_SELECTOR, &sregs.es);
+ kvm_seg_set_kernel_data_64bit(NULL, DEFAULT_DATA_SELECTOR, &sregs.gs);
kvm_setup_tss_64bit(vm, &sregs.tr, 0x18);

sregs.cr3 = vm->pgd;
vcpu_sregs_set(vcpu, &sregs);
-
- vcpu_init_descriptor_tables(vcpu);
}

static void set_idt_entry(struct kvm_vm *vm, int vector, unsigned long addr,
--
2.44.0.291.gc1ea87d7ee-goog