diff options
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/core.c')
-rw-r--r-- | arch/x86/kernel/cpu/microcode/core.c | 40 |
1 files changed, 24 insertions, 16 deletions
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 6996413c78c3..2af69d27da62 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -44,7 +44,7 @@ #define DRIVER_VERSION "2.2" static struct microcode_ops *microcode_ops; -static bool dis_ucode_ldr; +static bool dis_ucode_ldr = true; LIST_HEAD(microcode_cache); @@ -76,6 +76,7 @@ struct cpu_info_ctx { static bool __init check_loader_disabled_bsp(void) { static const char *__dis_opt_str = "dis_ucode_ldr"; + u32 a, b, c, d; #ifdef CONFIG_X86_32 const char *cmdline = (const char *)__pa_nodebug(boot_command_line); @@ -88,8 +89,23 @@ static bool __init check_loader_disabled_bsp(void) bool *res = &dis_ucode_ldr; #endif - if (cmdline_find_option_bool(cmdline, option)) - *res = true; + if (!have_cpuid_p()) + return *res; + + a = 1; + c = 0; + native_cpuid(&a, &b, &c, &d); + + /* + * CPUID(1).ECX[31]: reserved for hypervisor use. This is still not + * completely accurate as xen pv guests don't see that CPUID bit set but + * that's good enough as they don't land on the BSP path anyway. + */ + if (c & BIT(31)) + return *res; + + if (cmdline_find_option_bool(cmdline, option) <= 0) + *res = false; return *res; } @@ -121,9 +137,6 @@ void __init load_ucode_bsp(void) if (check_loader_disabled_bsp()) return; - if (!have_cpuid_p()) - return; - vendor = x86_cpuid_vendor(); family = x86_cpuid_family(); @@ -157,9 +170,6 @@ void load_ucode_ap(void) if (check_loader_disabled_ap()) return; - if (!have_cpuid_p()) - return; - vendor = x86_cpuid_vendor(); family = x86_cpuid_family(); @@ -233,14 +243,12 @@ struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa) # endif /* - * Did we relocate the ramdisk? - * - * So we possibly relocate the ramdisk *after* applying microcode on the - * BSP so we rely on use_pa (use physical addresses) - even if it is not - * absolutely correct - to determine whether we've done the ramdisk - * relocation already. + * Fixup the start address: after reserve_initrd() runs, initrd_start + * has the virtual address of the beginning of the initrd. It also + * possibly relocates the ramdisk. In either case, initrd_start contains + * the updated address so use that instead. */ - if (!use_pa && relocated_ramdisk) + if (!use_pa && initrd_start) start = initrd_start; return find_cpio_data(path, (void *)start, size, NULL); |