diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2019-02-18 22:51:43 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-16 19:45:14 +0200 |
| commit | 3fb41b4e2d389f2b187e2e12a7c8611d6c4b0e30 (patch) | |
| tree | a308c4e96e0ebabcaee360322cf15e25d70e844a /arch/x86/kernel/cpu/bugs.c | |
| parent | 1e9a9ef6703375c863f9cd1832b3cf5985aad055 (diff) | |
x86/speculation/mds: Add sysfs reporting for MDS
commit 8a4b06d391b0a42a373808979b5028f5c84d9c6a upstream.
Add the sysfs reporting file for MDS. It exposes the vulnerability and
mitigation state similar to the existing files for the other speculative
hardware vulnerabilities.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
[bwh: Backported to 4.4:
- Test x86_hyper instead of using hypervisor_is_type()
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kernel/cpu/bugs.c')
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 396d6b4034fe..999666648672 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -24,6 +24,7 @@ #include <asm/msr.h> #include <asm/paravirt.h> #include <asm/alternative.h> +#include <asm/hypervisor.h> #include <asm/pgtable.h> #include <asm/cacheflush.h> #include <asm/intel-family.h> @@ -1066,6 +1067,24 @@ static void __init l1tf_select_mitigation(void) #ifdef CONFIG_SYSFS +static ssize_t mds_show_state(char *buf) +{ +#ifdef CONFIG_HYPERVISOR_GUEST + if (x86_hyper) { + return sprintf(buf, "%s; SMT Host state unknown\n", + mds_strings[mds_mitigation]); + } +#endif + + if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) { + return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation], + sched_smt_active() ? "mitigated" : "disabled"); + } + + return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation], + sched_smt_active() ? "vulnerable" : "disabled"); +} + static char *stibp_state(void) { if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED) @@ -1128,6 +1147,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr return sprintf(buf, "Mitigation: Page Table Inversion\n"); break; + case X86_BUG_MDS: + return mds_show_state(buf); + default: break; } @@ -1159,4 +1181,9 @@ ssize_t cpu_show_l1tf(struct device *dev, struct device_attribute *attr, char *b { return cpu_show_common(dev, attr, buf, X86_BUG_L1TF); } + +ssize_t cpu_show_mds(struct device *dev, struct device_attribute *attr, char *buf) +{ + return cpu_show_common(dev, attr, buf, X86_BUG_MDS); +} #endif |