From: Sohil Mehta <sohil.mehta@intel.com>
To: kvm@vger.kernel.org, x86@kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Jonathan Corbet <corbet@lwn.net>,
Shuah Khan <skhan@linuxfoundation.org>,
Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H . Peter Anvin" <hpa@zytor.com>, Xin Li <xin@zytor.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Andrew Cooper <andrew.cooper3@citrix.com>,
Tom Lendacky <thomas.lendacky@amd.com>,
Nikunj A Dadhania <nikunj@amd.com>,
Shivansh Dhiman <shivansh.dhiman@amd.com>,
David Woodhouse <dwmw@amazon.co.uk>,
Chao Gao <chao.gao@intel.com>,
Binbin Wu <binbin.wu@linux.intel.com>,
Sohil Mehta <sohil.mehta@intel.com>,
Zhao Liu <zhao1.liu@intel.com>, Yosry Ahmed <yosry@kernel.org>,
David Matlack <dmatlack@google.com>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-kselftest@vger.kernel.org
Subject: [PATCH v10 27/28] KVM: selftests: Add a new VM guest mode to run user level code
Date: Fri, 11 Sep 2026 14:36:57 -0700 [thread overview]
Message-ID: <20260911213659.2025974-28-sohil.mehta@intel.com> (raw)
In-Reply-To: <20260911213659.2025974-1-sohil.mehta@intel.com>
From: "Xin Li (Intel)" <xin@zytor.com>
Add a new VM guest mode VM_MODE_PXXV48_4K_USER to set the user bit of
guest page table entries, thus allow user level code to run in guests.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
---
v10:
- Treat as new patch (last posted in v2).
---
tools/testing/selftests/kvm/include/kvm_util.h | 1 +
tools/testing/selftests/kvm/lib/kvm_util.c | 5 ++++-
tools/testing/selftests/kvm/lib/x86/processor.c | 16 ++++++++++++----
3 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 5a7a455b5387..981adfcbd5fa 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -191,6 +191,7 @@ enum vm_guest_mode {
VM_MODE_P40V48_16K,
VM_MODE_P40V48_64K,
VM_MODE_PXXVYY_4K, /* For 48-bit or 57-bit VA, depending on host support */
+ VM_MODE_PXXVYY_4K_USER, /* For 48bits VA but ANY bits PA with USER bit set */
VM_MODE_P47V64_4K,
VM_MODE_P44V64_4K,
VM_MODE_P36V48_4K,
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 9ddc047d5c27..e79fddedaf39 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -210,6 +210,7 @@ const char *vm_guest_mode_string(u32 i)
[VM_MODE_P40V48_16K] = "PA-bits:40, VA-bits:48, 16K pages",
[VM_MODE_P40V48_64K] = "PA-bits:40, VA-bits:48, 64K pages",
[VM_MODE_PXXVYY_4K] = "PA-bits:ANY, VA-bits:48 or 57, 4K pages",
+ [VM_MODE_PXXVYY_4K_USER]= "PA-bits:ANY, VA-bits:48, 4K user pages",
[VM_MODE_P47V64_4K] = "PA-bits:47, VA-bits:64, 4K pages",
[VM_MODE_P44V64_4K] = "PA-bits:44, VA-bits:64, 4K pages",
[VM_MODE_P36V48_4K] = "PA-bits:36, VA-bits:48, 4K pages",
@@ -246,6 +247,7 @@ const struct vm_guest_mode_params vm_guest_mode_params[] = {
[VM_MODE_P40V48_16K] = { 40, 48, 0x4000, 14 },
[VM_MODE_P40V48_64K] = { 40, 48, 0x10000, 16 },
[VM_MODE_PXXVYY_4K] = { 0, 0, 0x1000, 12 },
+ [VM_MODE_PXXVYY_4K_USER]= { 0, 0, 0x1000, 12 },
[VM_MODE_P47V64_4K] = { 47, 64, 0x1000, 12 },
[VM_MODE_P44V64_4K] = { 44, 64, 0x1000, 12 },
[VM_MODE_P36V48_4K] = { 36, 48, 0x1000, 12 },
@@ -337,6 +339,7 @@ struct kvm_vm *____vm_create(struct vm_shape shape)
vm->mmu.pgtable_levels = 3;
break;
case VM_MODE_PXXVYY_4K:
+ case VM_MODE_PXXVYY_4K_USER:
#ifdef __x86_64__
kvm_get_cpu_address_width(&vm->pa_bits, &vm->va_bits);
kvm_init_vm_address_properties(vm);
@@ -355,7 +358,7 @@ struct kvm_vm *____vm_create(struct vm_shape shape)
vm->mmu.pgtable_levels = 4;
}
#else
- TEST_FAIL("VM_MODE_PXXVYY_4K not supported on non-x86 platforms");
+ TEST_FAIL("VM_MODE_PXXVYY_4K(_USER) not supported on non-x86 platforms");
#endif
break;
case VM_MODE_P47V64_4K:
diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c
index d31fa81ea075..51d713c4c9de 100644
--- a/tools/testing/selftests/kvm/lib/x86/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86/processor.c
@@ -167,6 +167,9 @@ bool kvm_is_tdp_enabled(void)
static void virt_mmu_init(struct kvm_vm *vm, struct kvm_mmu *mmu,
struct pte_masks *pte_masks)
{
+ TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K || vm->mode == VM_MODE_PXXVYY_4K_USER,
+ "Unknown or unsupported guest mode: 0x%x", vm->mode);
+
/* If needed, create the top-level page table. */
if (!mmu->pgd_created) {
mmu->pgd = vm_alloc_page_table(vm);
@@ -181,7 +184,7 @@ static void virt_mmu_init(struct kvm_vm *vm, struct kvm_mmu *mmu,
void virt_arch_pgd_alloc(struct kvm_vm *vm)
{
- TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K,
+ TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K || vm->mode == VM_MODE_PXXVYY_4K_USER,
"Unknown or unsupported guest mode: 0x%x", vm->mode);
struct pte_masks pte_masks = (struct pte_masks){
@@ -239,6 +242,8 @@ static u64 *virt_create_upper_pte(struct kvm_vm *vm,
*pte = PTE_PRESENT_MASK(mmu) | PTE_READABLE_MASK(mmu) |
PTE_WRITABLE_MASK(mmu) | PTE_EXECUTABLE_MASK(mmu) |
PTE_ALWAYS_SET_MASK(mmu);
+ if (vm->mode == VM_MODE_PXXVYY_4K_USER)
+ *pte |= PTE_USER_MASK(mmu);
if (current_level == target_level)
*pte |= PTE_HUGE_MASK(mmu) | (gpa & PHYSICAL_PAGE_MASK);
else
@@ -266,7 +271,7 @@ void __virt_pg_map(struct kvm_vm *vm, struct kvm_mmu *mmu, gva_t gva,
u64 *pte = &mmu->pgd;
int current_level;
- TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K,
+ TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K || vm->mode == VM_MODE_PXXVYY_4K_USER,
"Unknown or unsupported guest mode: 0x%x", vm->mode);
TEST_ASSERT((gva % pg_size) == 0,
@@ -316,6 +321,9 @@ void __virt_pg_map(struct kvm_vm *vm, struct kvm_mmu *mmu, gva_t gva,
*pte |= PTE_C_BIT_MASK(mmu);
else
*pte |= PTE_S_BIT_MASK(mmu);
+
+ if (vm->mode == VM_MODE_PXXVYY_4K_USER)
+ *pte |= PTE_USER_MASK(mmu);
}
void virt_arch_pg_map(struct kvm_vm *vm, gva_t gva, gpa_t gpa)
@@ -372,7 +380,7 @@ static u64 *__vm_get_page_table_entry(struct kvm_vm *vm,
TEST_ASSERT(*level >= PG_LEVEL_NONE && *level <= mmu->pgtable_levels,
"Invalid PG_LEVEL_* '%d'", *level);
- TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K,
+ TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K || vm->mode == VM_MODE_PXXVYY_4K_USER,
"Unknown or unsupported guest mode: 0x%x", vm->mode);
TEST_ASSERT(sparsebit_is_set(vm->vpages_valid, (gva >> vm->page_shift)),
"Invalid virtual address, gva: 0x%lx", gva);
@@ -645,7 +653,7 @@ static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
{
struct kvm_sregs sregs;
- TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K,
+ TEST_ASSERT(vm->mode == VM_MODE_PXXVYY_4K || vm->mode == VM_MODE_PXXVYY_4K_USER,
"Unknown or unsupported guest mode: 0x%x", vm->mode);
/* Set mode specific system register values. */
--
2.43.0
next prev parent reply other threads:[~2026-09-11 21:44 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-11 21:36 [PATCH v10 00/28] KVM: Enable FRED support with KVM VMX Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 01/28] KVM: VMX: Enable support for secondary VM exit controls Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 02/28] KVM: VMX: Initialize VM entry/exit FRED controls in vmcs_config Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 03/28] KVM: VMX: Disable FRED if FRED consistency checks fail Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 04/28] x86/cea: Prefix event stack names with ESTACK_ Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 05/28] x86/cea: Use array indexing to simplify exception stack access Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 06/28] x86/fred: Export this_cpu_fred_rsp() for KVM usage Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 07/28] KVM: VMX: Initialize VMCS FRED fields Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 08/28] KVM: VMX: Set FRED MSR intercepts Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 09/28] KVM: VMX: Save/restore guest FRED RSP0 Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 10/28] KVM: VMX: Add support for saving and restoring FRED MSRs Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 11/28] KVM: x86: Add a helper to detect if FRED is enabled for a vCPU Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 12/28] KVM: x86: Add a new save/restore flag for FRED metadata Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 13/28] KVM: VMX: Virtualize FRED nested exception tracking Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 14/28] KVM: VMX: Virtualize FRED event_data Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 15/28] KVM: x86: Include CR4.FRED in the emulator CR4 write mask Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 16/28] KVM: x86: Mark CR4.FRED as not reserved Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 17/28] KVM: x86: Handle CR4.FRED when emulating RSM Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 18/28] KVM: VMX: Dump FRED context in dump_vmcs() Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 19/28] KVM: x86: Advertise support for FRED Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 20/28] KVM: nVMX: Enable support for secondary VM exit controls Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 21/28] KVM: nVMX: Handle FRED VMCS fields in nested VMX context Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 22/28] KVM: nVMX: Restrict event data VMCS fields to FRED-supported hosts Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 23/28] KVM: nVMX: Shadow ORIGINAL_EVENT_DATA and INJECTED_EVENT_DATA fields Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 24/28] KVM: nVMX: Validate FRED-related VMCS fields Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 25/28] KVM: nVMX: Enable VMX FRED controls Sohil Mehta
2026-09-11 21:36 ` [PATCH v10 26/28] KVM: selftests: Add FRED MSRs to msrs_test Sohil Mehta
2026-09-11 21:36 ` Sohil Mehta [this message]
2026-09-11 21:36 ` [PATCH v10 28/28] KVM: selftests: Add fred exception tests Sohil Mehta
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