diff mbox series

[v19,019/130] KVM: x86: Add is_vm_type_supported callback

Message ID 6712a8a18abb033b1c32b9b6579ac297e3b00ab6.1708933498.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series [v19,001/130] x86/virt/tdx: Rename _offset to _member for TD_SYSINFO_MAP() macro | expand

Commit Message

Isaku Yamahata Feb. 26, 2024, 8:25 a.m. UTC 
From: Isaku Yamahata <isaku.yamahata@intel.com>

For SEV_SNP and TDX, allow the backend can override the supported vm type.
Add KVM_X86_SNP_VM and KVM_X86_TDX_VM to reserve the bit.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>

---
v19:
- Mention KVM_X86_SNP_VM to the commit message

v18:
- include into TDX KVM patch series v18

Changes v3 -> v4:
- Added KVM_X86_SNP_VM

Changes v2 -> v3:
- no change
- didn't bother to rename KVM_X86_PROTECTED_VM to KVM_X86_SW_PROTECTED_VM

Changes v1 -> v2
- no change

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/include/asm/kvm-x86-ops.h |  1 +
 arch/x86/include/asm/kvm_host.h    |  1 +
 arch/x86/include/uapi/asm/kvm.h    |  2 ++
 arch/x86/kvm/svm/svm.c             |  7 +++++++
 arch/x86/kvm/vmx/vmx.c             |  7 +++++++
 arch/x86/kvm/x86.c                 | 12 +++++++++++-
 arch/x86/kvm/x86.h                 |  2 ++
 7 files changed, 31 insertions(+), 1 deletion(-)

Comments

Chao Gao March 14, 2024, 8:32 a.m. UTC | #1 
>-static bool kvm_is_vm_type_supported(unsigned long type)
>+bool __kvm_is_vm_type_supported(unsigned long type)
> {
> 	return type == KVM_X86_DEFAULT_VM ||
> 	       (type == KVM_X86_SW_PROTECTED_VM &&
> 		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);

maybe just do:
	switch (type) {
	case KVM_X86_DEFAULT_VM:
		return true;
	case KVM_X86_SW_PROTECTED_VM:
		return IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled;
	default:
		return static_call(kvm_x86_is_vm_type_supported)(type);
	}

There are two benefits
1) switch/case improves readability a little.
2) no need to expose __kvm_is_vm_type_supported()


> }
>+EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);

>+
>+static bool kvm_is_vm_type_supported(unsigned long type)
>+{
>+	return static_call(kvm_x86_is_vm_type_supported)(type);
>+}
> 
> int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> {
>@@ -4784,6 +4790,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> 		r = BIT(KVM_X86_DEFAULT_VM);
> 		if (kvm_is_vm_type_supported(KVM_X86_SW_PROTECTED_VM))
> 			r |= BIT(KVM_X86_SW_PROTECTED_VM);
>+		if (kvm_is_vm_type_supported(KVM_X86_TDX_VM))
>+			r |= BIT(KVM_X86_TDX_VM);
>+		if (kvm_is_vm_type_supported(KVM_X86_SNP_VM))
>+			r |= BIT(KVM_X86_SNP_VM);

maybe use a for-loop?
Isaku Yamahata March 14, 2024, 4:13 p.m. UTC | #2 
On Thu, Mar 14, 2024 at 04:32:20PM +0800,
Chao Gao <chao.gao@intel.com> wrote:

> >-static bool kvm_is_vm_type_supported(unsigned long type)
> >+bool __kvm_is_vm_type_supported(unsigned long type)
> > {
> > 	return type == KVM_X86_DEFAULT_VM ||
> > 	       (type == KVM_X86_SW_PROTECTED_VM &&
> > 		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);
> 
> maybe just do:
> 	switch (type) {
> 	case KVM_X86_DEFAULT_VM:
> 		return true;
> 	case KVM_X86_SW_PROTECTED_VM:
> 		return IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled;
> 	default:
> 		return static_call(kvm_x86_is_vm_type_supported)(type);
> 	}
> 
> There are two benefits
> 1) switch/case improves readability a little.
> 2) no need to expose __kvm_is_vm_type_supported()

The following[1] patch will supersede this patch. Will drop this patch.

[1] https://lore.kernel.org/kvm/20240226190344.787149-12-pbonzini@redhat.com/
diff mbox series

Patch

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 156832f01ebe..8be71a5c5c87 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -20,6 +20,7 @@  KVM_X86_OP(hardware_disable)
 KVM_X86_OP(hardware_unsetup)
 KVM_X86_OP(has_emulated_msr)
 KVM_X86_OP(vcpu_after_set_cpuid)
+KVM_X86_OP(is_vm_type_supported)
 KVM_X86_OP(vm_init)
 KVM_X86_OP_OPTIONAL(vm_destroy)
 KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 28314e7d546c..37cda8aa07b6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1603,6 +1603,7 @@  struct kvm_x86_ops {
 	bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
 	void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
 
+	bool (*is_vm_type_supported)(unsigned long vm_type);
 	unsigned int vm_size;
 	int (*vm_init)(struct kvm *kvm);
 	void (*vm_destroy)(struct kvm *kvm);
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index a448d0964fc0..aa7a56a47564 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -564,5 +564,7 @@  struct kvm_pmu_event_filter {
 
 #define KVM_X86_DEFAULT_VM	0
 #define KVM_X86_SW_PROTECTED_VM	1
+#define KVM_X86_TDX_VM		2
+#define KVM_X86_SNP_VM		3
 
 #endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e90b429c84f1..f76dd52d29ba 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4886,6 +4886,12 @@  static void svm_vm_destroy(struct kvm *kvm)
 	sev_vm_destroy(kvm);
 }
 
+static bool svm_is_vm_type_supported(unsigned long type)
+{
+	/* FIXME: Check if CPU is capable of SEV-SNP. */
+	return __kvm_is_vm_type_supported(type);
+}
+
 static int svm_vm_init(struct kvm *kvm)
 {
 	if (!pause_filter_count || !pause_filter_thresh)
@@ -4914,6 +4920,7 @@  static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.vcpu_free = svm_vcpu_free,
 	.vcpu_reset = svm_vcpu_reset,
 
+	.is_vm_type_supported = svm_is_vm_type_supported,
 	.vm_size = sizeof(struct kvm_svm),
 	.vm_init = svm_vm_init,
 	.vm_destroy = svm_vm_destroy,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 1111d9d08903..fca3457dd050 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7541,6 +7541,12 @@  static int vmx_vcpu_create(struct kvm_vcpu *vcpu)
 	return err;
 }
 
+static bool vmx_is_vm_type_supported(unsigned long type)
+{
+	/* TODO: Check if TDX is supported. */
+	return __kvm_is_vm_type_supported(type);
+}
+
 #define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
 #define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
 
@@ -8263,6 +8269,7 @@  static struct kvm_x86_ops vmx_x86_ops __initdata = {
 	.hardware_disable = vmx_hardware_disable,
 	.has_emulated_msr = vmx_has_emulated_msr,
 
+	.is_vm_type_supported = vmx_is_vm_type_supported,
 	.vm_size = sizeof(struct kvm_vmx),
 	.vm_init = vmx_vm_init,
 	.vm_destroy = vmx_vm_destroy,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 03dab4266172..442b356e4939 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4576,12 +4576,18 @@  static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,
 }
 #endif
 
-static bool kvm_is_vm_type_supported(unsigned long type)
+bool __kvm_is_vm_type_supported(unsigned long type)
 {
 	return type == KVM_X86_DEFAULT_VM ||
 	       (type == KVM_X86_SW_PROTECTED_VM &&
 		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);
 }
+EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);
+
+static bool kvm_is_vm_type_supported(unsigned long type)
+{
+	return static_call(kvm_x86_is_vm_type_supported)(type);
+}
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 {
@@ -4784,6 +4790,10 @@  int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		r = BIT(KVM_X86_DEFAULT_VM);
 		if (kvm_is_vm_type_supported(KVM_X86_SW_PROTECTED_VM))
 			r |= BIT(KVM_X86_SW_PROTECTED_VM);
+		if (kvm_is_vm_type_supported(KVM_X86_TDX_VM))
+			r |= BIT(KVM_X86_TDX_VM);
+		if (kvm_is_vm_type_supported(KVM_X86_SNP_VM))
+			r |= BIT(KVM_X86_SNP_VM);
 		break;
 	default:
 		break;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 2f7e19166658..4e40c23d66ed 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -9,6 +9,8 @@ 
 #include "kvm_cache_regs.h"
 #include "kvm_emulate.h"
 
+bool __kvm_is_vm_type_supported(unsigned long type);
+
 struct kvm_caps {
 	/* control of guest tsc rate supported? */
 	bool has_tsc_control;