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author | Ingo Molnar <mingo@kernel.org> | 2018-03-12 12:10:03 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-03-12 12:10:03 +0100 |
commit | 3c76db70eb70a0fbd40b3e0dec8f69ca344d1ff8 (patch) | |
tree | a9dd314ac18992cdc2c50d4de60535a1b76ee351 /arch/x86/kernel/cpu/bugs.c | |
parent | 194a9749c73d650c0b1dfdee04fb0bdf0a888ba8 (diff) | |
parent | 7958b2246fadf54b7ff820a2a5a2c5ca1554716f (diff) | |
download | linux-3c76db70eb70a0fbd40b3e0dec8f69ca344d1ff8.tar.bz2 |
Merge branch 'x86/pti' into x86/mm, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/cpu/bugs.c')
-rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index d71c8b54b696..bfca937bdcc3 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -300,6 +300,15 @@ retpoline_auto: setup_force_cpu_cap(X86_FEATURE_USE_IBPB); pr_info("Spectre v2 mitigation: Enabling Indirect Branch Prediction Barrier\n"); } + + /* + * Retpoline means the kernel is safe because it has no indirect + * branches. But firmware isn't, so use IBRS to protect that. + */ + if (boot_cpu_has(X86_FEATURE_IBRS)) { + setup_force_cpu_cap(X86_FEATURE_USE_IBRS_FW); + pr_info("Enabling Restricted Speculation for firmware calls\n"); + } } #undef pr_fmt @@ -326,8 +335,9 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) return sprintf(buf, "Not affected\n"); - return sprintf(buf, "%s%s%s\n", spectre_v2_strings[spectre_v2_enabled], + return sprintf(buf, "%s%s%s%s\n", spectre_v2_strings[spectre_v2_enabled], boot_cpu_has(X86_FEATURE_USE_IBPB) ? ", IBPB" : "", + boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "", spectre_v2_module_string()); } #endif |