From b5475d8caedb71476f999a858ea3f8c24c5f9e50 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 21 Feb 2020 14:50:22 +0000 Subject: arm64: kvm: hyp: use cpus_have_final_cap() 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 Reviewed-by: Marc Zyngier Cc: James Morse Cc: Julien Thierry Cc: Suzuki Poulouse Cc: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kvm/hyp/tlb.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm64/kvm/hyp/tlb.c') 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 */ -- cgit v1.2.3-70-g09d2