Merge branch 'for-next/fpsimd' into for-next/core

* for-next/fpsimd:
  arm64: cpufeature: Warn if we attempt to read a zero width field
  arm64: cpufeature: Add missing .field_width for GIC system registers
  arm64: signal: nofpsimd: Do not allocate fp/simd context when not available
  arm64: cpufeature: Always specify and use a field width for capabilities
  arm64: Always use individual bits in CPACR floating point enables
  arm64: Define CPACR_EL1_FPEN similarly to other floating point controls

arch/arm64/include/asm/cpufeature.h

@@ -356,6 +356,7 @@ struct arm64_cpu_capabilities {
 		struct {	/* Feature register checking */
 			u32 sys_reg;
 			u8 field_pos;
+			u8 field_width;
 			u8 min_field_value;
 			u8 hwcap_type;
 			bool sign;
@@ -576,6 +577,8 @@ static inline u64 arm64_ftr_reg_user_value(const struct arm64_ftr_reg *reg)
 static inline int __attribute_const__
 cpuid_feature_extract_field_width(u64 features, int field, int width, bool sign)
 {
+	if (WARN_ON_ONCE(!width))
+		width = 4;
 	return (sign) ?
 		cpuid_feature_extract_signed_field_width(features, field, width) :
 		cpuid_feature_extract_unsigned_field_width(features, field, width);

arch/arm64/include/asm/kvm_arm.h

@@ -355,8 +355,8 @@
 	ECN(SOFTSTP_CUR), ECN(WATCHPT_LOW), ECN(WATCHPT_CUR), \
 	ECN(BKPT32), ECN(VECTOR32), ECN(BRK64)
 
-#define CPACR_EL1_FPEN		(3 << 20)
 #define CPACR_EL1_TTA		(1 << 28)
-#define CPACR_EL1_DEFAULT	(CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN)
+#define CPACR_EL1_DEFAULT	(CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN |\
+				 CPACR_EL1_ZEN_EL1EN)
 
 #endif /* __ARM64_KVM_ARM_H__ */

arch/arm64/include/asm/sysreg.h

@@ -1109,9 +1109,11 @@
 #define ZCR_ELx_LEN_SIZE	9
 #define ZCR_ELx_LEN_MASK	0x1ff
 
+#define CPACR_EL1_FPEN_EL1EN	(BIT(20)) /* enable EL1 access */
+#define CPACR_EL1_FPEN_EL0EN	(BIT(21)) /* enable EL0 access, if EL1EN set */
+
 #define CPACR_EL1_ZEN_EL1EN	(BIT(16)) /* enable EL1 access */
 #define CPACR_EL1_ZEN_EL0EN	(BIT(17)) /* enable EL0 access, if EL1EN set */
-#define CPACR_EL1_ZEN		(CPACR_EL1_ZEN_EL1EN | CPACR_EL1_ZEN_EL0EN)
 
 /* GCR_EL1 Definitions */
 #define SYS_GCR_EL1_RRND	(BIT(16))

arch/arm64/kernel/signal.c

@@ -576,10 +576,12 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user,
 {
 	int err;
 
-	err = sigframe_alloc(user, &user->fpsimd_offset,
-			     sizeof(struct fpsimd_context));
-	if (err)
-		return err;
+	if (system_supports_fpsimd()) {
+		err = sigframe_alloc(user, &user->fpsimd_offset,
+				     sizeof(struct fpsimd_context));
+		if (err)
+			return err;
+	}
 
 	/* fault information, if valid */
 	if (add_all || current->thread.fault_code) {

arch/arm64/kvm/hyp/include/hyp/switch.h

@@ -174,9 +174,9 @@ static bool kvm_hyp_handle_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code)
 
 	/* Valid trap.  Switch the context: */
 	if (has_vhe()) {
-		reg = CPACR_EL1_FPEN;
+		reg = CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN;
 		if (sve_guest)
-			reg |= CPACR_EL1_ZEN;
+			reg |= CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN;
 
 		sysreg_clear_set(cpacr_el1, 0, reg);
 	} else {

arch/arm64/kvm/hyp/vhe/switch.c

@@ -38,7 +38,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 
 	val = read_sysreg(cpacr_el1);
 	val |= CPACR_EL1_TTA;
-	val &= ~CPACR_EL1_ZEN;
+	val &= ~(CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN);
 
 	/*
 	 * With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to
@@ -53,9 +53,9 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 
 	if (update_fp_enabled(vcpu)) {
 		if (vcpu_has_sve(vcpu))
-			val |= CPACR_EL1_ZEN;
+			val |= CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN;
 	} else {
-		val &= ~CPACR_EL1_FPEN;
+		val &= ~(CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN);
 		__activate_traps_fpsimd32(vcpu);
 	}