From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2 3/3] KVM: x86: Move nested_ops out of kvm_x86_ops, to global kvm_nested_ops
Date: Tue, 30 Jun 2026 13:28:28 -0700 [thread overview]
Message-ID: <20260630202828.440724-4-seanjc@google.com> (raw)
In-Reply-To: <20260630202828.440724-1-seanjc@google.com>
Rework KVM's handling of per-vendor nested ops to copy the vendor's ops
into a global structure owned by common x86, i.e. treat nested ops just
like x86 and PMU ops. In addition to providing consistency across all ops
implementations, making a copy of the ops prevents changes to the vendor's
ops after KVM is initialized, i.e. guards against goofs where KVM *thinks*
it is updating nested ops, but which won't take effect now that KVM uses
static calls to invoke vendor hooks.
Ignoring the side effects of tagging {svm,vmx}_nested_ops as __initdata,
no functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/include/asm/kvm_host.h | 4 ++--
arch/x86/kvm/hyperv.c | 2 +-
arch/x86/kvm/svm/nested.c | 2 +-
arch/x86/kvm/svm/svm.c | 3 +--
arch/x86/kvm/vmx/main.c | 3 +--
arch/x86/kvm/vmx/nested.c | 2 +-
arch/x86/kvm/x86.c | 25 +++++++++++++------------
7 files changed, 20 insertions(+), 21 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 25b1e3c1b344..7e07a9c259d0 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1842,8 +1842,6 @@ struct kvm_x86_ops {
void (*update_cpu_dirty_logging)(struct kvm_vcpu *vcpu);
- const struct kvm_x86_nested_ops *nested_ops;
-
void (*vcpu_blocking)(struct kvm_vcpu *vcpu);
void (*vcpu_unblocking)(struct kvm_vcpu *vcpu);
@@ -1939,6 +1937,7 @@ struct kvm_x86_init_ops {
struct kvm_x86_ops *runtime_ops;
struct kvm_pmu_ops *pmu_ops;
+ struct kvm_x86_nested_ops *nested_ops;
};
struct kvm_arch_async_pf {
@@ -1954,6 +1953,7 @@ extern bool __read_mostly enable_apicv;
extern bool __read_mostly enable_ipiv;
extern bool __read_mostly enable_device_posted_irqs;
extern struct kvm_x86_ops kvm_x86_ops;
+extern struct kvm_x86_nested_ops kvm_nested_ops __read_mostly;
#define kvm_x86_call(func) static_call(kvm_x86_##func)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 8b396ccd847e..b010dca37b9d 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -2787,7 +2787,7 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
};
int i, nent = ARRAY_SIZE(cpuid_entries);
- if (kvm_x86_ops.nested_ops->enabled)
+ if (kvm_nested_ops.enabled)
evmcs_ver = kvm_nested_call(get_evmcs_version)(vcpu);
if (cpuid->nent < nent)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index ba985a02208a..5f6d9971a3f2 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -2162,7 +2162,7 @@ static gpa_t svm_translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa,
return w->gva_to_gpa(vcpu, w, gpa, access, exception);
}
-struct kvm_x86_nested_ops svm_nested_ops = {
+struct kvm_x86_nested_ops svm_nested_ops __initdata = {
.leave_nested = svm_leave_nested,
.translate_nested_gpa = svm_translate_nested_gpa,
.is_exception_vmexit = nested_svm_is_exception_vmexit,
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 163440fca59f..d3807f4abb49 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5426,8 +5426,6 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
.check_intercept = svm_check_intercept,
.handle_exit_irqoff = svm_handle_exit_irqoff,
- .nested_ops = &svm_nested_ops,
-
.deliver_interrupt = svm_deliver_interrupt,
.pi_update_irte = avic_pi_update_irte,
.setup_mce = svm_setup_mce,
@@ -5773,6 +5771,7 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = {
.runtime_ops = &svm_x86_ops,
.pmu_ops = &amd_pmu_ops,
+ .nested_ops = &svm_nested_ops,
};
static void __svm_exit(void)
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 83d9921277ea..04f986e3d439 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -995,8 +995,6 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.update_cpu_dirty_logging = vt_op(update_cpu_dirty_logging),
- .nested_ops = &vmx_nested_ops,
-
.pi_update_irte = vmx_pi_update_irte,
.pi_start_bypass = vmx_pi_start_bypass,
@@ -1038,6 +1036,7 @@ struct kvm_x86_init_ops vt_init_ops __initdata = {
.runtime_ops = &vt_x86_ops,
.pmu_ops = &intel_pmu_ops,
+ .nested_ops = &vmx_nested_ops,
};
static void __exit vt_exit(void)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 0635e92471c8..cbb209d8a8f0 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -7484,7 +7484,7 @@ static gpa_t vmx_translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa,
return w->gva_to_gpa(vcpu, w, gpa, access, exception);
}
-struct kvm_x86_nested_ops vmx_nested_ops = {
+struct kvm_x86_nested_ops vmx_nested_ops __initdata = {
.leave_nested = vmx_leave_nested,
.translate_nested_gpa = vmx_translate_nested_gpa,
.is_exception_vmexit = nested_vmx_is_exception_vmexit,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 792afd15582b..5ba4aac37640 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -154,6 +154,7 @@ static int sync_regs(struct kvm_vcpu *vcpu);
static DEFINE_MUTEX(vendor_module_lock);
struct kvm_x86_ops kvm_x86_ops __read_mostly;
+struct kvm_x86_nested_ops kvm_nested_ops __read_mostly;
#define KVM_X86_OP(func) \
DEFINE_STATIC_CALL_NULL(kvm_x86_##func, \
@@ -2353,16 +2354,14 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
r &= ~KVM_X2APIC_ENABLE_SUPPRESS_EOI_BROADCAST;
break;
case KVM_CAP_NESTED_STATE:
- r = kvm_x86_ops.nested_ops->enabled ?
- kvm_nested_call(get_state)(NULL, NULL, 0) : 0;
+ r = kvm_nested_ops.enabled ? kvm_nested_call(get_state)(NULL, NULL, 0) : 0;
break;
#ifdef CONFIG_KVM_HYPERV
case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
r = kvm_x86_ops.enable_l2_tlb_flush != NULL;
break;
case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
- r = kvm_x86_ops.nested_ops->enabled &&
- kvm_x86_ops.nested_ops->enable_evmcs != NULL;
+ r = kvm_nested_ops.enabled && kvm_nested_ops.enable_evmcs != NULL;
break;
#endif
case KVM_CAP_SMALLER_MAXPHYADDR:
@@ -3374,8 +3373,8 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
uint16_t vmcs_version;
void __user *user_ptr;
- if (!kvm_x86_ops.nested_ops->enabled ||
- !kvm_x86_ops.nested_ops->enable_evmcs)
+ if (!kvm_nested_ops.enabled ||
+ !kvm_nested_ops.enable_evmcs)
return -ENOTTY;
r = kvm_nested_call(enable_evmcs)(vcpu, &vmcs_version);
if (!r) {
@@ -3741,7 +3740,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
u32 user_data_size;
r = -EINVAL;
- if (!kvm_x86_ops.nested_ops->enabled)
+ if (!kvm_nested_ops.enabled)
break;
BUILD_BUG_ON(sizeof(user_data_size) != sizeof(user_kvm_nested_state->size));
@@ -3770,7 +3769,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
int idx;
r = -EINVAL;
- if (!kvm_x86_ops.nested_ops->enabled)
+ if (!kvm_nested_ops.enabled)
break;
r = -EFAULT;
@@ -6913,13 +6912,15 @@ static void kvm_setup_efer_caps(void)
static void kvm_nested_ops_update(const struct kvm_x86_nested_ops *nested_ops)
{
+ memcpy(&kvm_nested_ops, nested_ops, sizeof(kvm_nested_ops));
+
#define __KVM_X86_NESTED_OP(func) \
- static_call_update(kvm_x86_nested_##func, nested_ops->func);
+ static_call_update(kvm_x86_nested_##func, kvm_nested_ops.func);
#define KVM_X86_NESTED_OP(func) \
- WARN_ON(!nested_ops->func); __KVM_X86_NESTED_OP(func)
+ WARN_ON(!kvm_nested_ops.func); __KVM_X86_NESTED_OP(func)
#define KVM_X86_NESTED_OP_OPTIONAL __KVM_X86_NESTED_OP
#define KVM_X86_NESTED_OP_OPTIONAL_RET0(func) \
- static_call_update(kvm_x86_nested_##func, (void *)nested_ops->func ? : \
+ static_call_update(kvm_x86_nested_##func, (void *)kvm_nested_ops.func ? : \
(void *)__static_call_return0);
#include <asm/kvm-x86-nested-ops.h>
#undef __KVM_X86_NESTED_OP
@@ -6940,7 +6941,7 @@ static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
#include <asm/kvm-x86-ops.h>
#undef __KVM_X86_OP
- kvm_nested_ops_update(kvm_x86_ops.nested_ops);
+ kvm_nested_ops_update(ops->nested_ops);
kvm_pmu_ops_update(ops->pmu_ops);
}
--
2.55.0.rc0.799.gd6f94ed593-goog
prev parent reply other threads:[~2026-06-30 20:28 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-30 20:28 [PATCH v2 0/3] KVM: x86: Convert nested ops to static calls Sean Christopherson
2026-06-30 20:28 ` [PATCH v2 1/3] KVM: x86: Reject nested CAP enablement if nested virtualization is disabled Sean Christopherson
2026-07-10 12:56 ` Vitaly Kuznetsov
2026-06-30 20:28 ` [PATCH v2 2/3] KVM: x86: Add static calls for nested virtualization ops Sean Christopherson
2026-06-30 20:28 ` Sean Christopherson [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260630202828.440724-4-seanjc@google.com \
--to=seanjc@google.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=vkuznets@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox