From: Jiri Kosina <[email protected]> If spectrev2 mitigation has been enabled, we're filling RSB on context switch in order to protect from various classess of spectrev2 attacks.
If this mitigation is enabled, say so in sysfs for spectrev2. Signed-off-by: Jiri Kosina <[email protected]> --- arch/x86/kernel/cpu/bugs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 6bc76bdf5a0a..ee46dcbae5fa 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -875,10 +875,11 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr case X86_BUG_SPECTRE_V2: mutex_lock(&spec_ctrl_mutex); - ret = sprintf(buf, "%s%s%s%s%s\n", spectre_v2_strings[spectre_v2_enabled], + ret = sprintf(buf, "%s%s%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" : "", (x86_spec_ctrl_base & SPEC_CTRL_STIBP) ? ", STIBP" : "", + boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "", spectre_v2_module_string()); mutex_unlock(&spec_ctrl_mutex); return ret; -- Jiri Kosina SUSE Labs
