KVM: arm64: Simplify install_bp_hardening_cb()

Use is_hyp_mode_available() to detect whether or not we need to patch
the KVM vectors for branch hardening, which avoids the need to take the
vector pointers as parameters.

Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 135bf7f..a72ca57 100644 (file)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -126,18 +126,19 @@ static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
        __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
 }
 
-static void install_bp_hardening_cb(bp_hardening_cb_t fn,
-                                   const char *hyp_vecs_start,
-                                   const char *hyp_vecs_end)
+static void install_bp_hardening_cb(bp_hardening_cb_t fn)
 {
        static DEFINE_RAW_SPINLOCK(bp_lock);
        int cpu, slot = -1;
+       const char *hyp_vecs_start = __smccc_workaround_1_smc;
+       const char *hyp_vecs_end = __smccc_workaround_1_smc +
+                                  __SMCCC_WORKAROUND_1_SMC_SZ;
 
        /*
         * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if
         * we're a guest. Skip the hyp-vectors work.
         */
-       if (!hyp_vecs_start) {
+       if (!is_hyp_mode_available()) {
                __this_cpu_write(bp_hardening_data.fn, fn);
                return;
        }
@@ -161,9 +162,7 @@ static void install_bp_hardening_cb(bp_hardening_cb_t fn,
        raw_spin_unlock(&bp_lock);
 }
 #else
-static void install_bp_hardening_cb(bp_hardening_cb_t fn,
-                                     const char *hyp_vecs_start,
-                                     const char *hyp_vecs_end)
+static void install_bp_hardening_cb(bp_hardening_cb_t fn)
 {
        __this_cpu_write(bp_hardening_data.fn, fn);
 }
@@ -209,7 +208,6 @@ early_param("nospectre_v2", parse_nospectre_v2);
 static int detect_harden_bp_fw(void)
 {
        bp_hardening_cb_t cb;
-       void *smccc_start, *smccc_end;
        struct arm_smccc_res res;
        u32 midr = read_cpuid_id();
 
@@ -229,21 +227,10 @@ static int detect_harden_bp_fw(void)
        switch (arm_smccc_1_1_get_conduit()) {
        case SMCCC_CONDUIT_HVC:
                cb = call_hvc_arch_workaround_1;
-               /* This is a guest, no need to patch KVM vectors */
-               smccc_start = NULL;
-               smccc_end = NULL;
                break;
 
        case SMCCC_CONDUIT_SMC:
                cb = call_smc_arch_workaround_1;
-#if IS_ENABLED(CONFIG_KVM)
-               smccc_start = __smccc_workaround_1_smc;
-               smccc_end = __smccc_workaround_1_smc +
-                       __SMCCC_WORKAROUND_1_SMC_SZ;
-#else
-               smccc_start = NULL;
-               smccc_end = NULL;
-#endif
                break;
 
        default:
@@ -254,7 +241,7 @@ static int detect_harden_bp_fw(void)
            ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1))
                cb = qcom_link_stack_sanitization;
 
-       install_bp_hardening_cb(cb, smccc_start, smccc_end);
+       install_bp_hardening_cb(cb);
        return 1;
 }