From: Sean Christopherson <seanjc@google.com>
To: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>,
Michael Kelley <mikelley@microsoft.com>,
Siddharth Chandrasekaran <sidcha@amazon.de>,
Yuan Yao <yuan.yao@linux.intel.com>,
Maxim Levitsky <mlevitsk@redhat.com>,
linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v10 29/39] KVM: selftests: Export _vm_get_page_table_entry()
Date: Wed, 21 Sep 2022 22:13:16 +0000 [thread overview]
Message-ID: <YyuMfG51iMMfa2mR@google.com> (raw)
In-Reply-To: <20220921152436.3673454-30-vkuznets@redhat.com>
On Wed, Sep 21, 2022, Vitaly Kuznetsov wrote:
> Make it possible for tests to mangle guest's page table entries in
> addition to just getting them (available with vm_get_page_table_entry()).
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> tools/testing/selftests/kvm/include/x86_64/processor.h | 2 ++
> tools/testing/selftests/kvm/lib/x86_64/processor.c | 5 ++---
> 2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
> index 1c7805de8c27..500d711eb989 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/processor.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
> @@ -827,6 +827,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val)
> return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr));
> }
>
> +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
> + uint64_t vaddr);
> uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
> uint64_t vaddr);
> void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 2e6e61bbe81b..5c135f896ada 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -214,9 +214,8 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
> __virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K);
> }
>
> -static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm,
> - struct kvm_vcpu *vcpu,
> - uint64_t vaddr)
> +uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
> + uint64_t vaddr)
Ugh, obviously not your fault, but this is a terrible name. Aside from using a
single underscore, it's semantically very different than vm_get_page_table_entry(),
i.e. violates the stand "double underscores is an inner helper".
The innards of vm_{g,s}et_page_table_entry() are quite hilarious too as they cast
a "uint64_t *" to "uint64_t*" now that KVM no longer uses structs to manage PTEs
(commit f18b4aebe107 ("kvm: selftests: do not use bitfields larger than 32-bits
for PTEs")).
And looking at the sole usage in emulator_error_test.c, provide get+set helpers
is silly.
Rather than expose this weirdness, what about slotting in the below to drop the
wrappers and just let tests modify PTEs directly?
---
From: Sean Christopherson <seanjc@google.com>
Date: Wed, 21 Sep 2022 15:08:49 -0700
Subject: [PATCH] KVM: selftests: Drop helpers to read/write page table entries
Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
PTE, i.e. let tests directly modify PTEs instead of bouncing through
helpers that just make life difficult.
Opportunsitically use BIT_ULL() in emulator_error_test, and use the
MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
same value.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
.../selftests/kvm/include/x86_64/processor.h | 6 ++----
.../selftests/kvm/lib/x86_64/processor.c | 21 ++-----------------
.../kvm/x86_64/emulator_error_test.c | 6 ++++--
3 files changed, 8 insertions(+), 25 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 0cbc71b7af50..5999e974a150 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -825,10 +825,8 @@ static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val)
return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr));
}
-uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr);
-void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr, uint64_t pte);
+uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
+ uint64_t vaddr);
uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
uint64_t a3);
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 2e6e61bbe81b..5e4bbe71dbff 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -214,9 +214,8 @@ void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
__virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K);
}
-static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm,
- struct kvm_vcpu *vcpu,
- uint64_t vaddr)
+uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
+ uint64_t vaddr)
{
uint16_t index[4];
uint64_t *pml4e, *pdpe, *pde;
@@ -286,22 +285,6 @@ static uint64_t *_vm_get_page_table_entry(struct kvm_vm *vm,
return &pte[index[0]];
}
-uint64_t vm_get_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr)
-{
- uint64_t *pte = _vm_get_page_table_entry(vm, vcpu, vaddr);
-
- return *(uint64_t *)pte;
-}
-
-void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
- uint64_t vaddr, uint64_t pte)
-{
- uint64_t *new_pte = _vm_get_page_table_entry(vm, vcpu, vaddr);
-
- *(uint64_t *)new_pte = pte;
-}
-
void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
{
uint64_t *pml4e, *pml4e_start;
diff --git a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
index 236e11755ba6..bde247f3c8a1 100644
--- a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
+++ b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
@@ -152,8 +152,9 @@ int main(int argc, char *argv[])
{
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
- uint64_t gpa, pte;
+ uint64_t *pte;
uint64_t *hva;
+ uint64_t gpa;
int rc;
/* Tell stdout not to buffer its content */
@@ -178,8 +179,9 @@ int main(int argc, char *argv[])
virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1);
hva = addr_gpa2hva(vm, MEM_REGION_GPA);
memset(hva, 0, PAGE_SIZE);
+
pte = vm_get_page_table_entry(vm, vcpu, MEM_REGION_GVA);
- vm_set_page_table_entry(vm, vcpu, MEM_REGION_GVA, pte | (1ull << 36));
+ *pte |= BIT_ULL(MAXPHYADDR);
vcpu_run(vcpu);
process_exit_on_emulation_error(vcpu);
base-commit: 3b69d246e2f1eef553508c79f5d3b2dfc4978bc1
--
next prev parent reply other threads:[~2022-09-21 22:13 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-21 15:23 [PATCH v10 00/39] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush features Vitaly Kuznetsov
2022-09-21 15:23 ` [PATCH v10 01/39] KVM: x86: Rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush' Vitaly Kuznetsov
2022-09-21 15:23 ` [PATCH v10 02/39] KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag Vitaly Kuznetsov
2022-09-21 16:23 ` Sean Christopherson
2022-09-21 16:45 ` Sean Christopherson
2022-09-22 9:35 ` Vitaly Kuznetsov
2022-09-22 9:31 ` Vitaly Kuznetsov
2022-09-22 15:23 ` Sean Christopherson
2022-09-22 15:37 ` Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 03/39] KVM: x86: hyper-v: Introduce TLB flush fifo Vitaly Kuznetsov
2022-09-21 16:56 ` Sean Christopherson
2022-09-22 9:42 ` Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 04/39] KVM: x86: hyper-v: Add helper to read hypercall data for array Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 05/39] KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls gently Vitaly Kuznetsov
2022-09-21 17:00 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 06/39] KVM: x86: hyper-v: Expose support for extended gva ranges for flush hypercalls Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 07/39] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 08/39] x86/hyperv: Introduce HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 09/39] KVM: x86: hyper-v: Use HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK instead of raw '64' Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 10/39] KVM: x86: hyper-v: Don't use sparse_set_to_vcpu_mask() in kvm_hv_send_ipi() Vitaly Kuznetsov
2022-09-21 20:54 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 11/39] KVM: x86: hyper-v: Create a separate fifo for L2 TLB flush Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 12/39] KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv' instead of on-stack 'sparse_banks' Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 13/39] KVM: nVMX: Keep track of hv_vm_id/hv_vp_id when eVMCS is in use Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 14/39] KVM: nSVM: Keep track of Hyper-V hv_vm_id/hv_vp_id Vitaly Kuznetsov
2022-09-21 21:16 ` Sean Christopherson
2022-09-22 9:51 ` Vitaly Kuznetsov
2022-09-22 19:52 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 15/39] KVM: x86: Introduce .hv_inject_synthetic_vmexit_post_tlb_flush() nested hook Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 16/39] KVM: x86: hyper-v: Introduce kvm_hv_is_tlb_flush_hcall() Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 17/39] KVM: x86: hyper-v: L2 TLB flush Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 18/39] KVM: x86: hyper-v: Introduce fast guest_hv_cpuid_has_l2_tlb_flush() check Vitaly Kuznetsov
2022-09-21 21:19 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 19/39] KVM: nVMX: hyper-v: Cache VP assist page in 'struct kvm_vcpu_hv' Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 20/39] KVM: nVMX: hyper-v: Enable L2 TLB flush Vitaly Kuznetsov
2022-09-21 21:24 ` Sean Christopherson
2022-09-22 16:05 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 21/39] KVM: nSVM: " Vitaly Kuznetsov
2022-09-21 21:31 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 22/39] KVM: x86: Expose Hyper-V L2 TLB flush feature Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 23/39] KVM: selftests: Better XMM read/write helpers Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 24/39] KVM: selftests: Move HYPERV_LINUX_OS_ID definition to a common header Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 25/39] KVM: selftests: Move the function doing Hyper-V hypercall " Vitaly Kuznetsov
2022-09-21 21:51 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 26/39] KVM: selftests: Hyper-V PV IPI selftest Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 27/39] KVM: selftests: Fill in vm->vpages_mapped bitmap in virt_map() too Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 28/39] KVM: selftests: Export vm_vaddr_unused_gap() to make it possible to request unmapped ranges Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 29/39] KVM: selftests: Export _vm_get_page_table_entry() Vitaly Kuznetsov
2022-09-21 22:13 ` Sean Christopherson [this message]
2022-09-21 15:24 ` [PATCH v10 30/39] KVM: selftests: Hyper-V PV TLB flush selftest Vitaly Kuznetsov
2022-09-21 22:52 ` Sean Christopherson
2022-10-03 13:01 ` Vitaly Kuznetsov
2022-10-03 15:47 ` Sean Christopherson
2022-10-03 16:00 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 31/39] KVM: selftests: Sync 'struct hv_enlightened_vmcs' definition with hyperv-tlfs.h Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 32/39] KVM: selftests: Sync 'struct hv_vp_assist_page' " Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 33/39] KVM: selftests: Move Hyper-V VP assist page enablement out of evmcs.h Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 34/39] KVM: selftests: Split off load_evmcs() from load_vmcs() Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 35/39] KVM: selftests: Create a vendor independent helper to allocate Hyper-V specific test pages Vitaly Kuznetsov
2022-09-21 22:59 ` Sean Christopherson
2022-09-21 15:24 ` [PATCH v10 36/39] KVM: selftests: Allocate Hyper-V partition assist page Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 37/39] KVM: selftests: evmcs_test: Introduce L2 TLB flush test Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 38/39] KVM: selftests: hyperv_svm_test: " Vitaly Kuznetsov
2022-09-21 15:24 ` [PATCH v10 39/39] KVM: selftests: Rename 'evmcs_test' to 'hyperv_evmcs' Vitaly Kuznetsov
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