Jeremy Linton [off-list ref] hat am 18. Januar 2019 um 23:22 geschrieben:


On 01/18/2019 12:05 PM, Stefan Wahren wrote:

quoted

Hi,

...

a snippet or a new version would be nice

Sure, I've got another version, to be posted soon (probably Tue of next 
week).

In the meantime, Marc's tree should work with the following fix:

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index b44f87e7360d..7cfd34b2c0e5 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c

@@ -286,11 +286,15 @@ static int detect_harden_bp_fw(void)
  }
  #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */

+#if defined(CONFIG_ARM64_SSBD) || \
+       defined(CONFIG_GENERIC_CPU_VULNERABILITIES)
+static bool __ssb_safe = true;
+#endif
+
  #ifdef CONFIG_ARM64_SSBD
  DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);

  int ssbd_state __read_mostly = ARM64_SSBD_KERNEL;
-static bool __ssb_safe = true;

  static const struct ssbd_options {
         const char      *str;

@@ -569,6 +573,8 @@ check_branch_predictor(const struct 

arm64_cpu_capabilities *entry, int scope)

         WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());

+       arm64_requested_vuln_attrs |= VULN_SPECTREV2;
+
         /* If the CPU has CSV2 set, we're safe */
         if 
(cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64PFR0_EL1),
                                                  ID_AA64PFR0_CSV2_SHIFT))

@@ -578,17 +584,17 @@ check_branch_predictor(const struct 

arm64_cpu_capabilities *entry, int scope)
         if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list))
                 return false;

+       __spectrev2_safe = false;
+
         /* Fallback to firmware detection */
         need_wa = detect_harden_bp_fw();
         if (!need_wa)
                 return false;

-       __spectrev2_safe = false;
-
         if (need_wa < 0)
                 pr_warn_once("ARM_SMCCC_ARCH_WORKAROUND_1 missing from 
firmware\n");

-       arm64_requested_vuln_attrs |= VULN_SPECTREV2;
+

         return (need_wa > 0);
  }