From 34bbfdfb146be3ad485cbe526b2a1e9ce220649c Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 12 Sep 2022 17:22:04 +0100 Subject: [PATCH] arm64: alternatives: kvm: prepare for cap changes The KVM patching callbacks use cpus_have_final_cap() internally within has_vhe(), and subsequent patches will make it invalid to call cpus_have_final_cap() before alternatives patching has completed, and will mean that cpus_have_const_cap() will always fall back to dynamic checks prior to alternatives patching. In preparation for said change, this patch modifies the KVM patching callbacks to use cpus_have_cap() directly. This is not subject to patching, and will dynamically check the cpu_hwcaps array, which is functionally equivalent to the existing behaviour. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Cc: Ard Biesheuvel Cc: James Morse Cc: Joey Gouly Cc: Marc Zyngier Cc: Will Deacon Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20220912162210.3626215-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/kvm/va_layout.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index acdb7b3cc97d..91b22a014610 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -169,7 +169,7 @@ void __init kvm_update_va_mask(struct alt_instr *alt, * dictates it and we don't have any spare bits in the * address), NOP everything after masking the kernel VA. */ - if (has_vhe() || (!tag_val && i > 0)) { + if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN) || (!tag_val && i > 0)) { updptr[i] = cpu_to_le32(aarch64_insn_gen_nop()); continue; } @@ -193,7 +193,8 @@ void kvm_patch_vector_branch(struct alt_instr *alt, BUG_ON(nr_inst != 4); - if (!cpus_have_const_cap(ARM64_SPECTRE_V3A) || WARN_ON_ONCE(has_vhe())) + if (!cpus_have_cap(ARM64_SPECTRE_V3A) || + WARN_ON_ONCE(cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN))) return; /*