From fe22ea561ce0c4d78f4e8305c852ad6f4a432b6a Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 8 Oct 2019 17:39:29 +0200 Subject: [PATCH] arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB [ Upstream commit eb337cdfcd5dd3b10522c2f34140a73a4c285c30 ] 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 Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- 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 0ce4a6a..292625f 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -341,15 +341,17 @@ 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) -- 2.7.4