Commit 5af05b8d authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Borislav Petkov (AMD)
Browse files

x86/microcode/amd: Use cached microcode for AP load 



Now that the microcode cache is initialized before the APs are brought
up, there is no point in scanning builtin/initrd microcode during AP
loading.

Convert the AP loader to utilize the cache, which in turn makes the CPU
hotplug callback which applies the microcode after initrd/builtin is
gone, obsolete as the early loading during late hotplug operations
including the resume path depends now only on the cache.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.243426023@linutronix.de
parent a7939f01

arch/x86/kernel/cpu/microcode/amd.c

+11 −9
Original line number Diff line number Diff line
@@ -496,7 +496,7 @@ static bool get_builtin_microcode(struct cpio_data *cp, unsigned int family) 
	return false;

}



static void find_blobs_in_containers(unsigned int cpuid_1_eax, struct cpio_data *ret)

static void __init find_blobs_in_containers(unsigned int cpuid_1_eax, struct cpio_data *ret)

{

	struct cpio_data cp;
@@ -506,12 +506,12 @@ static void find_blobs_in_containers(unsigned int cpuid_1_eax, struct cpio_data 
	*ret = cp;

}



static void apply_ucode_from_containers(unsigned int cpuid_1_eax)

void __init load_ucode_amd_bsp(unsigned int cpuid_1_eax)

{

	struct cpio_data cp = { };



	/* Needed in load_microcode_amd() */

	ucode_cpu_info[smp_processor_id()].cpu_sig.sig = cpuid_1_eax;

	ucode_cpu_info[0].cpu_sig.sig = cpuid_1_eax;



	find_blobs_in_containers(cpuid_1_eax, &cp);

	if (!(cp.data && cp.size))
@@ -520,11 +520,6 @@ static void apply_ucode_from_containers(unsigned int cpuid_1_eax) 
	early_apply_microcode(cpuid_1_eax, cp.data, cp.size);

}



void load_ucode_amd_early(unsigned int cpuid_1_eax)

{

	return apply_ucode_from_containers(cpuid_1_eax);

}



static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size);



static int __init save_microcode_in_initrd(void)
@@ -608,7 +603,6 @@ static struct ucode_patch *find_patch(unsigned int cpu) 
	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;

	u16 equiv_id;





	equiv_id = find_equiv_id(&equiv_table, uci->cpu_sig.sig);

	if (!equiv_id)

		return NULL;
@@ -710,6 +704,14 @@ static enum ucode_state apply_microcode_amd(int cpu) 
	return ret;

}



void load_ucode_amd_ap(unsigned int cpuid_1_eax)

{

	unsigned int cpu = smp_processor_id();



	ucode_cpu_info[cpu].cpu_sig.sig = cpuid_1_eax;

	apply_microcode_amd(cpu);

}



static size_t install_equiv_cpu_table(const u8 *buf, size_t buf_size)

{

	u32 equiv_tbl_len;

arch/x86/kernel/cpu/microcode/core.c

+2 −13
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ void __init load_ucode_bsp(void) 
	if (intel)

		load_ucode_intel_bsp();

	else

		load_ucode_amd_early(cpuid_1_eax);

		load_ucode_amd_bsp(cpuid_1_eax);

}



void load_ucode_ap(void)
@@ -173,7 +173,7 @@ void load_ucode_ap(void) 
		break;

	case X86_VENDOR_AMD:

		if (x86_family(cpuid_1_eax) >= 0x10)

			load_ucode_amd_early(cpuid_1_eax);

			load_ucode_amd_ap(cpuid_1_eax);

		break;

	default:

		break;
@@ -494,15 +494,6 @@ static struct syscore_ops mc_syscore_ops = { 
	.resume	= microcode_bsp_resume,

};



static int mc_cpu_starting(unsigned int cpu)

{

	enum ucode_state err = microcode_ops->apply_microcode(cpu);



	pr_debug("%s: CPU%d, err: %d\n", __func__, cpu, err);



	return err == UCODE_ERROR;

}



static int mc_cpu_online(unsigned int cpu)

{

	struct device *dev = get_cpu_device(cpu);
@@ -590,8 +581,6 @@ static int __init microcode_init(void) 
	schedule_on_each_cpu(setup_online_cpu);



	register_syscore_ops(&mc_syscore_ops);

	cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",

				  mc_cpu_starting, NULL);

	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online",

				  mc_cpu_online, mc_cpu_down_prep);

arch/x86/kernel/cpu/microcode/internal.h

+0 −2
Original line number Diff line number Diff line
@@ -91,7 +91,6 @@ extern bool initrd_gone; 
#ifdef CONFIG_CPU_SUP_AMD

void load_ucode_amd_bsp(unsigned int family);

void load_ucode_amd_ap(unsigned int family);

void load_ucode_amd_early(unsigned int cpuid_1_eax);

int save_microcode_in_initrd_amd(unsigned int family);

void reload_ucode_amd(unsigned int cpu);

struct microcode_ops *init_amd_microcode(void);
@@ -99,7 +98,6 @@ void exit_amd_microcode(void); 
#else /* CONFIG_CPU_SUP_AMD */

static inline void load_ucode_amd_bsp(unsigned int family) { }

static inline void load_ucode_amd_ap(unsigned int family) { }

static inline void load_ucode_amd_early(unsigned int family) { }

static inline int save_microcode_in_initrd_amd(unsigned int family) { return -EINVAL; }

static inline void reload_ucode_amd(unsigned int cpu) { }

static inline struct microcode_ops *init_amd_microcode(void) { return NULL; }