diff mbox series

[v3,14/15] KVM: arm64: Convert the SVE guest vcpu flag to a vm flag

Message ID 20241128123515.1709777-15-tabba@google.com (mailing list archive)
State New
Headers show
Series KVM: arm64: Rework guest VM fixed feature handling and trapping in pKVM | expand

Commit Message

Fuad Tabba Nov. 28, 2024, 12:35 p.m. UTC
The vcpu flag GUEST_HAS_SVE is per-vcpu, but it is based on what
is now a per-vm feature. Make the flag per-vm.

Signed-off-by: Fuad Tabba <tabba@google.com>
---
 arch/arm64/include/asm/kvm_emulate.h    |  6 +++---
 arch/arm64/include/asm/kvm_host.h       | 10 ++++++----
 arch/arm64/kvm/hyp/include/hyp/switch.h |  2 +-
 arch/arm64/kvm/hyp/nvhe/hyp-main.c      |  2 +-
 arch/arm64/kvm/hyp/nvhe/pkvm.c          | 11 +++++++----
 arch/arm64/kvm/hyp/nvhe/switch.c        |  8 ++++----
 arch/arm64/kvm/hyp/vhe/switch.c         |  2 +-
 arch/arm64/kvm/reset.c                  |  2 +-
 8 files changed, 24 insertions(+), 19 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 406e99a452bf..ae6d0dc0e4ff 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -620,7 +620,7 @@  static __always_inline void kvm_write_cptr_el2(u64 val)
 }
 
 /* Resets the value of cptr_el2 when returning to the host. */
-static __always_inline void kvm_reset_cptr_el2(struct kvm_vcpu *vcpu)
+static __always_inline void kvm_reset_cptr_el2(struct kvm *kvm)
 {
 	u64 val;
 
@@ -631,14 +631,14 @@  static __always_inline void kvm_reset_cptr_el2(struct kvm_vcpu *vcpu)
 	} else if (has_hvhe()) {
 		val = CPACR_ELx_FPEN;
 
-		if (!vcpu_has_sve(vcpu) || !guest_owns_fp_regs())
+		if (!kvm_has_sve(kvm) || !guest_owns_fp_regs())
 			val |= CPACR_ELx_ZEN;
 		if (cpus_have_final_cap(ARM64_SME))
 			val |= CPACR_ELx_SMEN;
 	} else {
 		val = CPTR_NVHE_EL2_RES1;
 
-		if (vcpu_has_sve(vcpu) && guest_owns_fp_regs())
+		if (kvm_has_sve(kvm) && guest_owns_fp_regs())
 			val |= CPTR_EL2_TZ;
 		if (!cpus_have_final_cap(ARM64_SME))
 			val |= CPTR_EL2_TSM;
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 680ecef1d7aa..c5c80c789ad0 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -331,6 +331,8 @@  struct kvm_arch {
 #define KVM_ARCH_FLAG_ID_REGS_INITIALIZED		7
 	/* Fine-Grained UNDEF initialised */
 #define KVM_ARCH_FLAG_FGU_INITIALIZED			8
+	/* SVE exposed to guest */
+#define KVM_ARCH_FLAG_GUEST_HAS_SVE			9
 	unsigned long flags;
 
 	/* VM-wide vCPU feature set */
@@ -862,8 +864,6 @@  struct kvm_vcpu_arch {
 #define vcpu_set_flag(v, ...)	__vcpu_set_flag((v), __VA_ARGS__)
 #define vcpu_clear_flag(v, ...)	__vcpu_clear_flag((v), __VA_ARGS__)
 
-/* SVE exposed to guest */
-#define GUEST_HAS_SVE		__vcpu_single_flag(cflags, BIT(0))
 /* SVE config completed */
 #define VCPU_SVE_FINALIZED	__vcpu_single_flag(cflags, BIT(1))
 /* KVM_ARM_VCPU_INIT completed */
@@ -956,8 +956,10 @@  struct kvm_vcpu_arch {
 				 KVM_GUESTDBG_USE_HW | \
 				 KVM_GUESTDBG_SINGLESTEP)
 
-#define vcpu_has_sve(vcpu) (system_supports_sve() &&			\
-			    vcpu_get_flag(vcpu, GUEST_HAS_SVE))
+#define kvm_has_sve(kvm)	\
+	test_bit(KVM_ARCH_FLAG_GUEST_HAS_SVE, &(kvm)->arch.flags)
+#define vcpu_has_sve(vcpu)	\
+	kvm_has_sve((vcpu)->kvm)
 
 #ifdef CONFIG_ARM64_PTR_AUTH
 #define vcpu_has_ptrauth(vcpu)						\
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 34f53707892d..4c243673e1da 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -391,7 +391,7 @@  static bool kvm_hyp_handle_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code)
 	if (!system_supports_fpsimd())
 		return false;
 
-	sve_guest = vcpu_has_sve(vcpu);
+	sve_guest = kvm_has_sve(kern_hyp_va(vcpu->kvm));
 	esr_ec = kvm_vcpu_trap_get_class(vcpu);
 
 	/* Only handle traps the vCPU can support here: */
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 6aa0b13d86e5..226b6e289e08 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -71,7 +71,7 @@  static void fpsimd_sve_sync(struct kvm_vcpu *vcpu)
 	cpacr_clear_set(0, CPACR_ELx_FPEN | CPACR_ELx_ZEN);
 	isb();
 
-	if (vcpu_has_sve(vcpu))
+	if (kvm_has_sve(kern_hyp_va(vcpu->kvm)))
 		__hyp_sve_save_guest(vcpu);
 	else
 		__fpsimd_save_state(&vcpu->arch.ctxt.fp_regs);
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c
index dfd031acde31..8a80e494f20c 100644
--- a/arch/arm64/kvm/hyp/nvhe/pkvm.c
+++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c
@@ -248,10 +248,13 @@  void pkvm_put_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
 static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struct kvm *host_kvm)
 {
 	struct kvm *kvm = &hyp_vm->kvm;
+	unsigned long host_arch_flags = READ_ONCE(host_kvm->arch.flags);
 	DECLARE_BITMAP(allowed_features, KVM_VCPU_MAX_FEATURES);
 
 	/* No restrictions for non-protected VMs. */
 	if (!kvm_vm_is_protected(kvm)) {
+		hyp_vm->kvm.arch.flags = host_arch_flags;
+
 		bitmap_copy(kvm->arch.vcpu_features,
 			    host_kvm->arch.vcpu_features,
 			    KVM_VCPU_MAX_FEATURES);
@@ -271,8 +274,10 @@  static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struc
 	if (kvm_pvm_ext_allowed(KVM_CAP_ARM_PTRAUTH_GENERIC))
 		set_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, allowed_features);
 
-	if (kvm_pvm_ext_allowed(KVM_CAP_ARM_SVE))
+	if (kvm_pvm_ext_allowed(KVM_CAP_ARM_SVE)) {
 		set_bit(KVM_ARM_VCPU_SVE, allowed_features);
+		kvm->arch.flags |= host_arch_flags & BIT(KVM_ARCH_FLAG_GUEST_HAS_SVE);
+	}
 
 	bitmap_and(kvm->arch.vcpu_features, host_kvm->arch.vcpu_features,
 		   allowed_features, KVM_VCPU_MAX_FEATURES);
@@ -308,10 +313,8 @@  static void pkvm_vcpu_init_sve(struct pkvm_hyp_vcpu *hyp_vcpu, struct kvm_vcpu *
 {
 	struct kvm_vcpu *vcpu = &hyp_vcpu->vcpu;
 
-	if (!vcpu_has_feature(vcpu, KVM_ARM_VCPU_SVE)) {
-		vcpu_clear_flag(vcpu, GUEST_HAS_SVE);
+	if (!vcpu_has_feature(vcpu, KVM_ARM_VCPU_SVE))
 		vcpu_clear_flag(vcpu, VCPU_SVE_FINALIZED);
-	}
 }
 
 static int init_pkvm_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu,
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 0ebf84a9f9e2..b976c07c3108 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -44,7 +44,7 @@  static void __activate_cptr_traps(struct kvm_vcpu *vcpu)
 
 		if (guest_owns_fp_regs()) {
 			val |= CPACR_ELx_FPEN;
-			if (vcpu_has_sve(vcpu))
+			if (kvm_has_sve(kern_hyp_va(vcpu->kvm)))
 				val |= CPACR_ELx_ZEN;
 		}
 	} else {
@@ -56,7 +56,7 @@  static void __activate_cptr_traps(struct kvm_vcpu *vcpu)
 		 */
 		val |= CPTR_EL2_TSM;
 
-		if (!vcpu_has_sve(vcpu) || !guest_owns_fp_regs())
+		if (!kvm_has_sve(kern_hyp_va(vcpu->kvm)) || !guest_owns_fp_regs())
 			val |= CPTR_EL2_TZ;
 
 		if (!guest_owns_fp_regs())
@@ -119,7 +119,7 @@  static void __deactivate_traps(struct kvm_vcpu *vcpu)
 
 	write_sysreg(this_cpu_ptr(&kvm_init_params)->hcr_el2, hcr_el2);
 
-	kvm_reset_cptr_el2(vcpu);
+	kvm_reset_cptr_el2(kern_hyp_va(vcpu->kvm));
 	write_sysreg(__kvm_hyp_host_vector, vbar_el2);
 }
 
@@ -203,7 +203,7 @@  static void kvm_hyp_save_fpsimd_host(struct kvm_vcpu *vcpu)
 		__hyp_sve_save_host();
 
 		/* Re-enable SVE traps if not supported for the guest vcpu. */
-		if (!vcpu_has_sve(vcpu))
+		if (!kvm_has_sve(kern_hyp_va(vcpu->kvm)))
 			cpacr_clear_set(CPACR_ELx_ZEN, 0);
 
 	} else {
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 80581b1c3995..5407f82c2bec 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -207,7 +207,7 @@  static void __deactivate_traps(struct kvm_vcpu *vcpu)
 	 */
 	asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
 
-	kvm_reset_cptr_el2(vcpu);
+	kvm_reset_cptr_el2(vcpu->kvm);
 
 	if (!arm64_kernel_unmapped_at_el0())
 		host_vectors = __this_cpu_read(this_cpu_vector);
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 1cfab6a5d8a5..803e11b0dc8f 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -85,7 +85,7 @@  static void kvm_vcpu_enable_sve(struct kvm_vcpu *vcpu)
 	 * KVM_REG_ARM64_SVE_VLS.  Allocation is deferred until
 	 * kvm_arm_vcpu_finalize(), which freezes the configuration.
 	 */
-	vcpu_set_flag(vcpu, GUEST_HAS_SVE);
+	set_bit(KVM_ARCH_FLAG_GUEST_HAS_SVE, &vcpu->kvm->arch.flags);
 }
 
 /*