From 18f3ad4b97c7ee40c5c7a496d349e79b6477a814 Mon Sep 17 00:00:00 2001 From: Doug Berger Date: Mon, 11 Nov 2019 04:32:04 +0100 Subject: [PATCH] ARM: 8937/1: spectre-v2: remove Brahma-B53 from hardening [ Upstream commit 4ae5061a19b550dfe25397843427ed2ebab16b16 ] When the default processor handling was added to the function cpu_v7_spectre_init() it only excluded other ARM implemented processor cores. The Broadcom Brahma B53 core is not implemented by ARM so it ended up falling through into the set of processors that attempt to use the ARM_SMCCC_ARCH_WORKAROUND_1 service to harden the branch predictor. Since this workaround is not necessary for the Brahma-B53 this commit explicitly checks for it and prevents it from applying a branch predictor hardening workaround. Fixes: 10115105cb3a ("ARM: spectre-v2: add firmware based hardening") Signed-off-by: Doug Berger Signed-off-by: Florian Fainelli Signed-off-by: Russell King Signed-off-by: Sasha Levin --- arch/arm/mm/proc-v7-bugs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 9a07916af8dd..a6554fdb56c5 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -65,6 +65,9 @@ static void cpu_v7_spectre_init(void) break; #ifdef CONFIG_ARM_PSCI + case ARM_CPU_PART_BRAHMA_B53: + /* Requires no workaround */ + break; default: /* Other ARM CPUs require no workaround */ if (read_cpuid_implementor() == ARM_CPU_IMP_ARM) -- 2.11.0