The KVM hyp code is only run after system capabilities have been
finalized, and thus all const cap checks have been patched. This is
noted in in __cpu_init_hyp_mode(), where we BUG() if called too early:
| /*
| * Call initialization code, and switch to the full blown HYP code.
| * If the cpucaps haven't been finalized yet, something has gone very
| * wrong, and hyp will crash and burn when it uses any
| * cpus_have_const_cap() wrapper.
| */
Given this, the hyp code can use cpus_have_final_cap() and avoid
generating code to check the cpu_hwcaps array, which would be unsafe to
run in hyp context.
This patch migrate the KVM hyp code to cpus_have_final_cap(), avoiding
this redundant code generation, and making it possible to detect if we
accidentally invoke this code too early. In the latter case, the BUG()
in cpus_have_final_cap() will cause a hyp panic.
Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Julien Thierry <julien.thierry.kdev@xxxxxxxxx>
Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/switch.c | 14 +++++++-------
arch/arm64/kvm/hyp/sysreg-sr.c | 8 ++++----
arch/arm64/kvm/hyp/tlb.c | 8 ++++----
3 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index dfe8dd172512..27fcdff08dd6 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -127,7 +127,7 @@ static void __hyp_text __activate_traps_nvhe(struct kvm_vcpu *vcpu)
write_sysreg(val, cptr_el2);
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt;
isb();
@@ -146,12 +146,12 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
{
u64 hcr = vcpu->arch.hcr_el2;
- if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM))
+ if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM))
hcr |= HCR_TVM;
write_sysreg(hcr, hcr_el2);
- if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
+ if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2);
if (has_vhe())
@@ -181,7 +181,7 @@ static void __hyp_text __deactivate_traps_nvhe(void)
{
u64 mdcr_el2 = read_sysreg(mdcr_el2);
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
u64 val;
/*
@@ -328,7 +328,7 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
* resolve the IPA using the AT instruction.
*/
if (!(esr & ESR_ELx_S1PTW) &&
- (cpus_have_const_cap(ARM64_WORKAROUND_834220) ||
+ (cpus_have_final_cap(ARM64_WORKAROUND_834220) ||
(esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
if (!__translate_far_to_hpfar(far, &hpfar))
return false;
@@ -498,7 +498,7 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
if (*exit_code != ARM_EXCEPTION_TRAP)
goto exit;
- if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
+ if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 &&
handle_tx2_tvm(vcpu))
return true;
@@ -555,7 +555,7 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu)
{
- if (!cpus_have_const_cap(ARM64_SSBD))
+ if (!cpus_have_final_cap(ARM64_SSBD))
return false;
return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG);
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 7672a978926c..75b1925763f1 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -71,7 +71,7 @@ static void __hyp_text __sysreg_save_el2_return_state(struct kvm_cpu_context *ct
ctxt->gp_regs.regs.pc = read_sysreg_el2(SYS_ELR);
ctxt->gp_regs.regs.pstate = read_sysreg_el2(SYS_SPSR);
- if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN))
+ if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
ctxt->sys_regs[DISR_EL1] = read_sysreg_s(SYS_VDISR_EL2);
}
@@ -118,7 +118,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2);
write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1);
- if (!cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (!cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR);
write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR);
} else if (!ctxt->__hyp_running_vcpu) {
@@ -149,7 +149,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
write_sysreg(ctxt->sys_regs[PAR_EL1], par_el1);
write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1);
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE) &&
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE) &&
ctxt->__hyp_running_vcpu) {
/*
* Must only be done for host registers, hence the context
@@ -194,7 +194,7 @@ __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt)
write_sysreg_el2(ctxt->gp_regs.regs.pc, SYS_ELR);
write_sysreg_el2(pstate, SYS_SPSR);
- if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN))
+ if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
write_sysreg_s(ctxt->sys_regs[DISR_EL1], SYS_VDISR_EL2);
}
diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c
index 92f560e3e1aa..ceaddbe4279f 100644
--- a/arch/arm64/kvm/hyp/tlb.c
+++ b/arch/arm64/kvm/hyp/tlb.c
@@ -23,7 +23,7 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm,
local_irq_save(cxt->flags);
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
/*
* For CPUs that are affected by ARM errata 1165522 or 1530923,
* we cannot trust stage-1 to be in a correct state at that
@@ -63,7 +63,7 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm,
static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm,
struct tlb_inv_context *cxt)
{
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
u64 val;
/*
@@ -103,7 +103,7 @@ static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm,
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
isb();
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
/* Restore the registers to what they were */
write_sysreg_el1(cxt->tcr, SYS_TCR);
write_sysreg_el1(cxt->sctlr, SYS_SCTLR);
@@ -117,7 +117,7 @@ static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm,
{
write_sysreg(0, vttbr_el2);
- if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
/* Ensure write of the host VMID */
isb();
/* Restore the host's TCR_EL1 */
--
2.11.0
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