From: Will Deacon <will.deacon@arm.com>
Date: Tue, 30 Apr 2019 16:58:56 +0100
Subject: arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB
Git-commit: eb337cdfcd5dd3b10522c2f34140a73a4c285c30
Patch-mainline: v5.2-rc1
References: bsc#1174547
SSBS provides a relatively cheap mitigation for SSB, but it is still a
mitigation and its presence does not indicate that the CPU is unaffected
by the vulnerability.
Tweak the mitigation logic so that we report the correct string in sysfs.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
arch/arm64/kernel/cpu_errata.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 4bb0f7cad418..44ef98be001e 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -386,15 +386,17 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry,
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
+ /* delay setting __ssb_safe until we get a firmware response */
+ if (is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list))
+ this_cpu_safe = true;
+
if (this_cpu_has_cap(ARM64_SSBS)) {
+ if (!this_cpu_safe)
+ __ssb_safe = false;
required = false;
goto out_printmsg;
}
- /* delay setting __ssb_safe until we get a firmware response */
- if (is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list))
- this_cpu_safe = true;
-
if (psci_ops.smccc_version == SMCCC_VERSION_1_0) {
ssbd_state = ARM64_SSBD_UNKNOWN;
if (!this_cpu_safe)
--
2.26.2