3.2.101-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> commit 61dc0f555b5c761cdafb0ba5bd41ecf22d68a4c4 upstream. Implement the CPU vulnerabilty show functions for meltdown, spectre_v1 and spectre_v2. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: David Woodhouse <dwmw@xxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20180107214913.177414879@xxxxxxxxxxxxx [bwh: Backported to 3.2: - Meltdown mitigation feature flag is KAISER - Adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/x86/Kconfig | 1 + arch/x86/kernel/cpu/bugs.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+) --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -75,6 +75,7 @@ config X86 select HAVE_BPF_JIT if (X86_64 && NET) select CLKEVT_I8253 select ARCH_HAVE_NMI_SAFE_CMPXCHG + select GENERIC_CPU_VULNERABILITIES select ARCH_SUPPORTS_ATOMIC_RMW config INSTRUCTION_DECODER --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -9,6 +9,7 @@ */ #include <linux/init.h> #include <linux/utsname.h> +#include <linux/cpu.h> #include <asm/bugs.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -202,3 +203,31 @@ void __init check_bugs(void) set_memory_4k((unsigned long)__va(0), 1); #endif } + +#ifdef CONFIG_SYSFS +ssize_t cpu_show_meltdown(struct sysdev_class *dev, + struct sysdev_class_attribute *attr, char *buf) +{ + if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) + return sprintf(buf, "Not affected\n"); + if (boot_cpu_has(X86_FEATURE_KAISER)) + return sprintf(buf, "Mitigation: PTI\n"); + return sprintf(buf, "Vulnerable\n"); +} + +ssize_t cpu_show_spectre_v1(struct sysdev_class *dev, + struct sysdev_class_attribute *attr, char *buf) +{ + if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1)) + return sprintf(buf, "Not affected\n"); + return sprintf(buf, "Vulnerable\n"); +} + +ssize_t cpu_show_spectre_v2(struct sysdev_class *dev, + struct sysdev_class_attribute *attr, char *buf) +{ + if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) + return sprintf(buf, "Not affected\n"); + return sprintf(buf, "Vulnerable\n"); +} +#endif