3.16.77-rc1 review patch. If anyone has any objections, please let me know.
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From: Pawan Gupta pawan.kumar.gupta@linux.intel.com
commit 6608b45ac5ecb56f9e171252229c39580cc85f0f upstream.
Add the sysfs reporting file for TSX Async Abort. It exposes the vulnerability and the mitigation state similar to the existing files for the other hardware vulnerabilities.
Sysfs file path is: /sys/devices/system/cpu/vulnerabilities/tsx_async_abort
Signed-off-by: Pawan Gupta pawan.kumar.gupta@linux.intel.com Signed-off-by: Borislav Petkov bp@suse.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Neelima Krishnan neelima.krishnan@intel.com Reviewed-by: Mark Gross mgross@linux.intel.com Reviewed-by: Tony Luck tony.luck@intel.com Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Reviewed-by: Josh Poimboeuf jpoimboe@redhat.com Signed-off-by: Ben Hutchings ben@decadent.org.uk --- arch/x86/kernel/cpu/bugs.c | 23 +++++++++++++++++++++++ drivers/base/cpu.c | 9 +++++++++ include/linux/cpu.h | 3 +++ 3 files changed, 35 insertions(+)
--- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1365,6 +1365,21 @@ static ssize_t mds_show_state(char *buf) sched_smt_active() ? "vulnerable" : "disabled"); }
+static ssize_t tsx_async_abort_show_state(char *buf) +{ + if ((taa_mitigation == TAA_MITIGATION_TSX_DISABLED) || + (taa_mitigation == TAA_MITIGATION_OFF)) + return sprintf(buf, "%s\n", taa_strings[taa_mitigation]); + + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) { + return sprintf(buf, "%s; SMT Host state unknown\n", + taa_strings[taa_mitigation]); + } + + return sprintf(buf, "%s; SMT %s\n", taa_strings[taa_mitigation], + sched_smt_active() ? "vulnerable" : "disabled"); +} + static char *stibp_state(void) { if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED) @@ -1430,6 +1445,9 @@ static ssize_t cpu_show_common(struct de case X86_BUG_MDS: return mds_show_state(buf);
+ case X86_BUG_TAA: + return tsx_async_abort_show_state(buf); + default: break; } @@ -1466,4 +1484,9 @@ ssize_t cpu_show_mds(struct device *dev, { return cpu_show_common(dev, attr, buf, X86_BUG_MDS); } + +ssize_t cpu_show_tsx_async_abort(struct device *dev, struct device_attribute *attr, char *buf) +{ + return cpu_show_common(dev, attr, buf, X86_BUG_TAA); +} #endif --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -456,12 +456,20 @@ ssize_t __weak cpu_show_mds(struct devic return sprintf(buf, "Not affected\n"); }
+ssize_t __weak cpu_show_tsx_async_abort(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "Not affected\n"); +} + static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL); static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL); static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL); static DEVICE_ATTR(spec_store_bypass, 0444, cpu_show_spec_store_bypass, NULL); static DEVICE_ATTR(l1tf, 0444, cpu_show_l1tf, NULL); static DEVICE_ATTR(mds, 0444, cpu_show_mds, NULL); +static DEVICE_ATTR(tsx_async_abort, 0444, cpu_show_tsx_async_abort, NULL);
static struct attribute *cpu_root_vulnerabilities_attrs[] = { &dev_attr_meltdown.attr, @@ -470,6 +478,7 @@ static struct attribute *cpu_root_vulner &dev_attr_spec_store_bypass.attr, &dev_attr_l1tf.attr, &dev_attr_mds.attr, + &dev_attr_tsx_async_abort.attr, NULL };
--- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -51,6 +51,9 @@ extern ssize_t cpu_show_l1tf(struct devi struct device_attribute *attr, char *buf); extern ssize_t cpu_show_mds(struct device *dev, struct device_attribute *attr, char *buf); +extern ssize_t cpu_show_tsx_async_abort(struct device *dev, + struct device_attribute *attr, + char *buf);
#ifdef CONFIG_HOTPLUG_CPU extern void unregister_cpu(struct cpu *cpu);