| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20240314232637.2538648-18-seanjc@google.com>
Date: Thu, 14 Mar 2024 16:26:36 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>,
Paolo Bonzini <pbonzini@...hat.com>, Christian Borntraeger <borntraeger@...ux.ibm.com>,
Janosch Frank <frankja@...ux.ibm.com>, Claudio Imbrenda <imbrenda@...ux.ibm.com>,
Sean Christopherson <seanjc@...gle.com>, Anup Patel <anup@...infault.org>,
Paul Walmsley <paul.walmsley@...ive.com>, Palmer Dabbelt <palmer@...belt.com>,
Albert Ou <aou@...s.berkeley.edu>
Cc: linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev,
kvm@...r.kernel.org, kvm-riscv@...ts.infradead.org,
linux-riscv@...ts.infradead.org, linux-kernel@...r.kernel.org,
Ackerley Tng <ackerleytng@...gle.com>
Subject: [PATCH 17/18] KVM: selftests: Init x86's segments during VM creation
Initialize x86's various segments in the GDT during creation of relevant
VMs instead of waiting until vCPUs come along. Re-installing the segments
for every vCPU is both wasteful and confusing, as is installing KERNEL_DS
multiple times; NOT installing KERNEL_DS for GS is icing on the cake.
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
.../selftests/kvm/lib/x86_64/processor.c | 68 ++++++-------------
1 file changed, 20 insertions(+), 48 deletions(-)
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 67235013f6f9..dab719ee7734 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -438,24 +438,7 @@ static void kvm_seg_fill_gdt_64bit(struct kvm_vm *vm, struct kvm_segment *segp)
desc->base3 = segp->base >> 32;
}
-
-/*
- * Set Long Mode Flat Kernel Code Segment
- *
- * Input Args:
- * vm - VM whose GDT is being filled, or NULL to only write segp
- * selector - selector value
- *
- * Output Args:
- * segp - Pointer to KVM segment
- *
- * Return: None
- *
- * Sets up the KVM segment pointed to by @segp, to be a code segment
- * with the selector value given by @selector.
- */
-static void kvm_seg_set_kernel_code_64bit(struct kvm_vm *vm, uint16_t selector,
- struct kvm_segment *segp)
+static void kvm_seg_set_kernel_code_64bit(uint16_t selector, struct kvm_segment *segp)
{
memset(segp, 0, sizeof(*segp));
segp->selector = selector;
@@ -467,27 +450,9 @@ static void kvm_seg_set_kernel_code_64bit(struct kvm_vm *vm, uint16_t selector,
segp->g = true;
segp->l = true;
segp->present = 1;
- if (vm)
- kvm_seg_fill_gdt_64bit(vm, segp);
}
-/*
- * Set Long Mode Flat Kernel Data Segment
- *
- * Input Args:
- * vm - VM whose GDT is being filled, or NULL to only write segp
- * selector - selector value
- *
- * Output Args:
- * segp - Pointer to KVM segment
- *
- * Return: None
- *
- * Sets up the KVM segment pointed to by @segp, to be a data segment
- * with the selector value given by @selector.
- */
-static void kvm_seg_set_kernel_data_64bit(struct kvm_vm *vm, uint16_t selector,
- struct kvm_segment *segp)
+static void kvm_seg_set_kernel_data_64bit(uint16_t selector, struct kvm_segment *segp)
{
memset(segp, 0, sizeof(*segp));
segp->selector = selector;
@@ -498,8 +463,6 @@ static void kvm_seg_set_kernel_data_64bit(struct kvm_vm *vm, uint16_t selector,
*/
segp->g = true;
segp->present = true;
- if (vm)
- kvm_seg_fill_gdt_64bit(vm, segp);
}
vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
@@ -517,16 +480,15 @@ 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_tss_64bit(struct kvm_vm *vm, struct kvm_segment *segp,
- int selector)
+static void kvm_seg_set_tss_64bit(vm_vaddr_t base, struct kvm_segment *segp,
+ int selector)
{
memset(segp, 0, sizeof(*segp));
- segp->base = vm->arch.tss;
+ segp->base = base;
segp->limit = 0x67;
segp->selector = selector;
segp->type = 0xb;
segp->present = 1;
- kvm_seg_fill_gdt_64bit(vm, segp);
}
static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
@@ -548,11 +510,11 @@ static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
sregs.efer |= (EFER_LME | EFER_LMA | EFER_NX);
kvm_seg_set_unusable(&sregs.ldt);
- kvm_seg_set_kernel_code_64bit(vm, KERNEL_CS, &sregs.cs);
- kvm_seg_set_kernel_data_64bit(vm, KERNEL_DS, &sregs.ds);
- kvm_seg_set_kernel_data_64bit(vm, KERNEL_DS, &sregs.es);
- kvm_seg_set_kernel_data_64bit(NULL, KERNEL_DS, &sregs.gs);
- kvm_setup_tss_64bit(vm, &sregs.tr, KERNEL_TSS);
+ kvm_seg_set_kernel_code_64bit(KERNEL_CS, &sregs.cs);
+ kvm_seg_set_kernel_data_64bit(KERNEL_DS, &sregs.ds);
+ kvm_seg_set_kernel_data_64bit(KERNEL_DS, &sregs.es);
+ kvm_seg_set_kernel_data_64bit(KERNEL_DS, &sregs.gs);
+ kvm_seg_set_tss_64bit(vm->arch.tss, &sregs.tr, KERNEL_TSS);
sregs.cr3 = vm->pgd;
vcpu_sregs_set(vcpu, &sregs);
@@ -612,6 +574,7 @@ void route_exception(struct ex_regs *regs)
static void vm_init_descriptor_tables(struct kvm_vm *vm)
{
extern void *idt_handlers;
+ struct kvm_segment seg;
int i;
vm->arch.gdt = __vm_vaddr_alloc_page(vm, MEM_REGION_DATA);
@@ -624,6 +587,15 @@ static void vm_init_descriptor_tables(struct kvm_vm *vm)
set_idt_entry(vm, i, (unsigned long)(&idt_handlers)[i], 0, KERNEL_CS);
*(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers;
+
+ kvm_seg_set_kernel_code_64bit(KERNEL_CS, &seg);
+ kvm_seg_fill_gdt_64bit(vm, &seg);
+
+ kvm_seg_set_kernel_data_64bit(KERNEL_DS, &seg);
+ kvm_seg_fill_gdt_64bit(vm, &seg);
+
+ kvm_seg_set_tss_64bit(vm->arch.tss, &seg, KERNEL_TSS);
+ kvm_seg_fill_gdt_64bit(vm, &seg);
}
void vm_install_exception_handler(struct kvm_vm *vm, int vector,
--
2.44.0.291.gc1ea87d7ee-goog
Powered by blists - more mailing lists