[PATCH 4.15 095/163] arm64: Add missing Falkor part number for branch predictor hardening

Greg Kroah-Hartman
2018-02-21T12:48:44Z

From: Shanker Donthineni <shankerd@codeaurora.org>

commit 16e574d762ac5512eb922ac0ac5eed360b7db9d8 upstream.

References to CPU part number MIDR_QCOM_FALKOR were dropped from the
mailing list patch due to mainline/arm64 branch dependency. So this
patch adds the missing part number.

Fixes: ec82b567a74f ("arm64: Implement branch predictor hardening for Falkor")
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arm64/kernel/cpu_errata.c | 9 +++++++++
arch/arm64/kvm/hyp/switch.c | 4 +++-
2 files changed, 12 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -408,6 +408,15 @@ const struct arm64_cpu_capabilities arm6
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
+ MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
+ .enable = qcom_enable_link_stack_sanitization,
+ },
+ {
+ .capability = ARM64_HARDEN_BP_POST_GUEST_EXIT,
+ MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
+ },
+ {
+ .capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
.enable = enable_smccc_arch_workaround_1,
},
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -400,8 +400,10 @@ again:
u32 midr = read_cpuid_id();

/* Apply BTAC predictors mitigation to all Falkor chips */
- if ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)
+ if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) ||
+ ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) {
__qcom_hyp_sanitize_btac_predictors();
+ }
}

fp_enabled = __fpsimd_enabled();