diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/Kconfig | 19 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 4 |
2 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ad8bbb0a34f7..12c3b9c0da0c 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2387,6 +2387,25 @@ config ARCH_ENABLE_SPLIT_PMD_PTLOCK def_bool y depends on X86_64 || X86_PAE +config GDS_FORCE_MITIGATION + bool "Force GDS Mitigation" + depends on CPU_SUP_INTEL + default n + help + Gather Data Sampling (GDS) is a hardware vulnerability which allows + unprivileged speculative access to data which was previously stored in + vector registers. + + This option is equivalent to setting gather_data_sampling=force on the + command line. The microcode mitigation is used if present, otherwise + AVX is disabled as a mitigation. On affected systems that are missing + the microcode any userspace code that unconditionally uses AVX will + break with this option set. + + Setting this option on systems not vulnerable to GDS has no effect. + + If in doubt, say N. + config ARCH_ENABLE_HUGEPAGE_MIGRATION def_bool y depends on X86_64 && HUGETLB_PAGE && MIGRATION diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 54deb7569820..0de5482fb8c0 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -613,7 +613,11 @@ enum gds_mitigations { GDS_MITIGATION_HYPERVISOR, }; +#if IS_ENABLED(CONFIG_GDS_FORCE_MITIGATION) +static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FORCE; +#else static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FULL; +#endif static const char * const gds_strings[] = { [GDS_MITIGATION_OFF] = "Vulnerable", |