From 22765f30dbaf1118c6ff0fcb8b99c9f2b4d396d5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 10 Apr 2018 11:36:44 +0100 Subject: [PATCH] arm64: Get rid of __smccc_workaround_1_hvc_* The very existence of __smccc_workaround_1_hvc_* is a thinko, as KVM will never use a HVC call to perform the branch prediction invalidation. Even as a nested hypervisor, it would use an SMC instruction. Let's get rid of it. Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon --- arch/arm64/kernel/bpi.S | 12 ++---------- arch/arm64/kernel/cpu_errata.c | 9 +++------ 2 files changed, 5 insertions(+), 16 deletions(-) diff --git a/arch/arm64/kernel/bpi.S b/arch/arm64/kernel/bpi.S index 9404f6aecda7..279e6ced7611 100644 --- a/arch/arm64/kernel/bpi.S +++ b/arch/arm64/kernel/bpi.S @@ -74,21 +74,13 @@ ENTRY(__bp_harden_hyp_vecs_end) .popsection -.macro smccc_workaround_1 inst +ENTRY(__smccc_workaround_1_smc_start) sub sp, sp, #(8 * 4) stp x2, x3, [sp, #(8 * 0)] stp x0, x1, [sp, #(8 * 2)] mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1 - \inst #0 + smc #0 ldp x2, x3, [sp, #(8 * 0)] ldp x0, x1, [sp, #(8 * 2)] add sp, sp, #(8 * 4) -.endm - -ENTRY(__smccc_workaround_1_smc_start) - smccc_workaround_1 smc ENTRY(__smccc_workaround_1_smc_end) - -ENTRY(__smccc_workaround_1_hvc_start) - smccc_workaround_1 hvc -ENTRY(__smccc_workaround_1_hvc_end) diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 4e9f6a36d5e6..fc9d017f2d33 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -89,8 +89,6 @@ DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); #ifdef CONFIG_KVM extern char __smccc_workaround_1_smc_start[]; extern char __smccc_workaround_1_smc_end[]; -extern char __smccc_workaround_1_hvc_start[]; -extern char __smccc_workaround_1_hvc_end[]; static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start, const char *hyp_vecs_end) @@ -132,8 +130,6 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn, #else #define __smccc_workaround_1_smc_start NULL #define __smccc_workaround_1_smc_end NULL -#define __smccc_workaround_1_hvc_start NULL -#define __smccc_workaround_1_hvc_end NULL static void __install_bp_hardening_cb(bp_hardening_cb_t fn, const char *hyp_vecs_start, @@ -207,8 +203,9 @@ enable_smccc_arch_workaround_1(const struct arm64_cpu_capabilities *entry) if ((int)res.a0 < 0) return; cb = call_hvc_arch_workaround_1; - smccc_start = __smccc_workaround_1_hvc_start; - smccc_end = __smccc_workaround_1_hvc_end; + /* This is a guest, no need to patch KVM vectors */ + smccc_start = NULL; + smccc_end = NULL; break; case PSCI_CONDUIT_SMC: -- 2.30.2