[PATCH v4 2/8] KVM: arm64: Make vcpu_{read,write}_sys_reg available to HYP code
From: Fuad Tabba <hidden>
Date: 2026-07-06 10:00:13
Also in:
kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
The vcpu_{read,write}_sys_reg() accessors are host-only, so helpers
built on them such as kvm_vcpu_set_be()/kvm_vcpu_is_be() cannot be
shared with hyp code. exception.c already wraps them in
__vcpu_{read,write}_sys_reg(), which pick the host- or hyp-side accessor
via has_vhe() and so are valid in any context.
Move those wrappers to kvm_emulate.h as kvm_vcpu_{read,write}_sys_reg()
and switch the callers over, so a follow-up series can share that
emulation code at EL2.
No functional change intended.
Reviewed-by: Vincent Donnefort <redacted>
Signed-off-by: Fuad Tabba <redacted>
---
arch/arm64/include/asm/kvm_emulate.h | 22 +++++++++++++++---
arch/arm64/kvm/hyp/exception.c | 34 ++++++++--------------------
2 files changed, 28 insertions(+), 28 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 5bf3d7e1d92c7..80b30fead3d16 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h@@ -506,6 +506,22 @@ static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu) return __vcpu_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK; } +static inline u64 kvm_vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) +{ + if (has_vhe()) + return vcpu_read_sys_reg(vcpu, reg); + + return __vcpu_sys_reg(vcpu, reg); +} + +static inline void kvm_vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) +{ + if (has_vhe()) + vcpu_write_sys_reg(vcpu, val, reg); + else + __vcpu_assign_sys_reg(vcpu, reg, val); +} + static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu) { if (vcpu_mode_is_32bit(vcpu)) {
@@ -516,9 +532,9 @@ static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu) r = vcpu_has_nv(vcpu) ? SCTLR_EL2 : SCTLR_EL1; - sctlr = vcpu_read_sys_reg(vcpu, r); + sctlr = kvm_vcpu_read_sys_reg(vcpu, r); sctlr |= SCTLR_ELx_EE; - vcpu_write_sys_reg(vcpu, sctlr, r); + kvm_vcpu_write_sys_reg(vcpu, sctlr, r); } }
@@ -533,7 +549,7 @@ static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu) r = is_hyp_ctxt(vcpu) ? SCTLR_EL2 : SCTLR_EL1; bit = vcpu_mode_priv(vcpu) ? SCTLR_ELx_EE : SCTLR_EL1_E0E; - return vcpu_read_sys_reg(vcpu, r) & bit; + return kvm_vcpu_read_sys_reg(vcpu, r) & bit; } static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c
index bef40ddb16dbc..2cb68dc7d441e 100644
--- a/arch/arm64/kvm/hyp/exception.c
+++ b/arch/arm64/kvm/hyp/exception.c@@ -20,22 +20,6 @@ #error Hypervisor code only! #endif -static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) -{ - if (has_vhe()) - return vcpu_read_sys_reg(vcpu, reg); - - return __vcpu_sys_reg(vcpu, reg); -} - -static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) -{ - if (has_vhe()) - vcpu_write_sys_reg(vcpu, val, reg); - else - __vcpu_assign_sys_reg(vcpu, reg, val); -} - static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long target_mode, u64 val) {
@@ -101,14 +85,14 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, switch (target_mode) { case PSR_MODE_EL1h: - vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL1); - sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); - __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); + vbar = kvm_vcpu_read_sys_reg(vcpu, VBAR_EL1); + sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1); + kvm_vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); break; case PSR_MODE_EL2h: - vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL2); - sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL2); - __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2); + vbar = kvm_vcpu_read_sys_reg(vcpu, VBAR_EL2); + sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL2); + kvm_vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2); break; default: /* Don't do that */
@@ -185,7 +169,7 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, */ static unsigned long get_except32_cpsr(struct kvm_vcpu *vcpu, u32 mode) { - u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); + u32 sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1); unsigned long old, new; old = *vcpu_cpsr(vcpu);
@@ -281,7 +265,7 @@ static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset) { unsigned long spsr = *vcpu_cpsr(vcpu); bool is_thumb = (spsr & PSR_AA32_T_BIT); - u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); + u32 sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1); u32 return_address; *vcpu_cpsr(vcpu) = get_except32_cpsr(vcpu, mode);
@@ -305,7 +289,7 @@ static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset) if (sctlr & (1 << 13)) vect_offset += 0xffff0000; else /* always have security exceptions */ - vect_offset += __vcpu_read_sys_reg(vcpu, VBAR_EL1); + vect_offset += kvm_vcpu_read_sys_reg(vcpu, VBAR_EL1); *vcpu_pc(vcpu) = vect_offset; }
--
2.39.5