Merge tag 'x86_microcode_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 microcode loading updates from Borislav Petkov:
 "The first, cleanup part of the microcode loader reorg tglx has been
  working on. The other part wasn't fully ready in time so it will
  follow on later.

  This part makes the loader core code as it is practically enabled on
  pretty much every baremetal machine so there's no need to have the
  Kconfig items.

  In addition, there are cleanups which prepare for future feature
  enablement"

* tag 'x86_microcode_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode: Remove remaining references to CONFIG_MICROCODE_AMD
  x86/microcode/intel: Remove pointless mutex
  x86/microcode/intel: Remove debug code
  x86/microcode: Move core specific defines to local header
  x86/microcode/intel: Rename get_datasize() since its used externally
  x86/microcode: Make reload_early_microcode() static
  x86/microcode: Include vendor headers into microcode.h
  x86/microcode/intel: Move microcode functions out of cpu/intel.c
  x86/microcode: Hide the config knob
  x86/mm: Remove unused microcode.h include
  x86/microcode: Remove microcode_mutex
  x86/microcode/AMD: Rip out static buffers

7 files changed, 414 insertions, 355 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 281fc3f6ea6b..41b573f34a10 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -59,7 +59,6 @@
 #include <asm/cacheinfo.h>
 #include <asm/memtype.h>
 #include <asm/microcode.h>
-#include <asm/microcode_intel.h>
 #include <asm/intel-family.h>
 #include <asm/cpu_device_id.h>
 #include <asm/uv/uv.h>
@@ -2300,8 +2299,7 @@ void store_cpu_caps(struct cpuinfo_x86 *curr_info)
  * @prev_info:	CPU capabilities stored before an update.
  *
  * The microcode loader calls this upon late microcode load to recheck features,
- * only when microcode has been updated. Caller holds microcode_mutex and CPU
- * hotplug lock.
+ * only when microcode has been updated. Caller holds and CPU hotplug lock.
  *
  * Return: None
  */
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 1c4639588ff9..be4045628fd3 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -20,7 +20,7 @@
 #include <asm/bugs.h>
 #include <asm/cpu.h>
 #include <asm/intel-family.h>
-#include <asm/microcode_intel.h>
+#include <asm/microcode.h>
 #include <asm/hwcap2.h>
 #include <asm/elf.h>
 #include <asm/cpu_device_id.h>
@@ -184,180 +184,6 @@ static bool bad_spectre_microcode(struct cpuinfo_x86 *c)
 	return false;
 }
 
-int intel_cpu_collect_info(struct ucode_cpu_info *uci)
-{
-	unsigned int val[2];
-	unsigned int family, model;
-	struct cpu_signature csig = { 0 };
-	unsigned int eax, ebx, ecx, edx;
-
-	memset(uci, 0, sizeof(*uci));
-
-	eax = 0x00000001;
-	ecx = 0;
-	native_cpuid(&eax, &ebx, &ecx, &edx);
-	csig.sig = eax;
-
-	family = x86_family(eax);
-	model  = x86_model(eax);
-
-	if (model >= 5 || family > 6) {
-		/* get processor flags from MSR 0x17 */
-		native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
-		csig.pf = 1 << ((val[1] >> 18) & 7);
-	}
-
-	csig.rev = intel_get_microcode_revision();
-
-	uci->cpu_sig = csig;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(intel_cpu_collect_info);
-
-/*
- * Returns 1 if update has been found, 0 otherwise.
- */
-int intel_find_matching_signature(void *mc, unsigned int csig, int cpf)
-{
-	struct microcode_header_intel *mc_hdr = mc;
-	struct extended_sigtable *ext_hdr;
-	struct extended_signature *ext_sig;
-	int i;
-
-	if (intel_cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
-		return 1;
-
-	/* Look for ext. headers: */
-	if (get_totalsize(mc_hdr) <= get_datasize(mc_hdr) + MC_HEADER_SIZE)
-		return 0;
-
-	ext_hdr = mc + get_datasize(mc_hdr) + MC_HEADER_SIZE;
-	ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
-
-	for (i = 0; i < ext_hdr->count; i++) {
-		if (intel_cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
-			return 1;
-		ext_sig++;
-	}
-	return 0;
-}
-EXPORT_SYMBOL_GPL(intel_find_matching_signature);
-
-/**
- * intel_microcode_sanity_check() - Sanity check microcode file.
- * @mc: Pointer to the microcode file contents.
- * @print_err: Display failure reason if true, silent if false.
- * @hdr_type: Type of file, i.e. normal microcode file or In Field Scan file.
- *            Validate if the microcode header type matches with the type
- *            specified here.
- *
- * Validate certain header fields and verify if computed checksum matches
- * with the one specified in the header.
- *
- * Return: 0 if the file passes all the checks, -EINVAL if any of the checks
- * fail.
- */
-int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type)
-{
-	unsigned long total_size, data_size, ext_table_size;
-	struct microcode_header_intel *mc_header = mc;
-	struct extended_sigtable *ext_header = NULL;
-	u32 sum, orig_sum, ext_sigcount = 0, i;
-	struct extended_signature *ext_sig;
-
-	total_size = get_totalsize(mc_header);
-	data_size = get_datasize(mc_header);
-
-	if (data_size + MC_HEADER_SIZE > total_size) {
-		if (print_err)
-			pr_err("Error: bad microcode data file size.\n");
-		return -EINVAL;
-	}
-
-	if (mc_header->ldrver != 1 || mc_header->hdrver != hdr_type) {
-		if (print_err)
-			pr_err("Error: invalid/unknown microcode update format. Header type %d\n",
-			       mc_header->hdrver);
-		return -EINVAL;
-	}
-
-	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
-	if (ext_table_size) {
-		u32 ext_table_sum = 0;
-		u32 *ext_tablep;
-
-		if (ext_table_size < EXT_HEADER_SIZE ||
-		    ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
-			if (print_err)
-				pr_err("Error: truncated extended signature table.\n");
-			return -EINVAL;
-		}
-
-		ext_header = mc + MC_HEADER_SIZE + data_size;
-		if (ext_table_size != exttable_size(ext_header)) {
-			if (print_err)
-				pr_err("Error: extended signature table size mismatch.\n");
-			return -EFAULT;
-		}
-
-		ext_sigcount = ext_header->count;
-
-		/*
-		 * Check extended table checksum: the sum of all dwords that
-		 * comprise a valid table must be 0.
-		 */
-		ext_tablep = (u32 *)ext_header;
-
-		i = ext_table_size / sizeof(u32);
-		while (i--)
-			ext_table_sum += ext_tablep[i];
-
-		if (ext_table_sum) {
-			if (print_err)
-				pr_warn("Bad extended signature table checksum, aborting.\n");
-			return -EINVAL;
-		}
-	}
-
-	/*
-	 * Calculate the checksum of update data and header. The checksum of
-	 * valid update data and header including the extended signature table
-	 * must be 0.
-	 */
-	orig_sum = 0;
-	i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
-	while (i--)
-		orig_sum += ((u32 *)mc)[i];
-
-	if (orig_sum) {
-		if (print_err)
-			pr_err("Bad microcode data checksum, aborting.\n");
-		return -EINVAL;
-	}
-
-	if (!ext_table_size)
-		return 0;
-
-	/*
-	 * Check extended signature checksum: 0 => valid.
-	 */
-	for (i = 0; i < ext_sigcount; i++) {
-		ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
-			  EXT_SIGNATURE_SIZE * i;
-
-		sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
-		      (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
-		if (sum) {
-			if (print_err)
-				pr_err("Bad extended signature checksum, aborting.\n");
-			return -EINVAL;
-		}
-	}
-	return 0;
-}
-EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
-
 static void early_init_intel(struct cpuinfo_x86 *c)
 {
 	u64 misc_enable;
diff --git a/arch/x86/kernel/cpu/microcode/Makefile b/arch/x86/kernel/cpu/microcode/Makefile
index 34098d48c48f..193d98b33a0a 100644
--- a/arch/x86/kernel/cpu/microcode/Makefile
+++ b/arch/x86/kernel/cpu/microcode/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
 microcode-y				:= core.o
 obj-$(CONFIG_MICROCODE)			+= microcode.o
-microcode-$(CONFIG_MICROCODE_INTEL)	+= intel.o
-microcode-$(CONFIG_MICROCODE_AMD)	+= amd.o
+microcode-$(CONFIG_CPU_SUP_INTEL)	+= intel.o
+microcode-$(CONFIG_CPU_SUP_AMD)		+= amd.o
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 87208e46f7ed..bbd1dc38ea03 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -29,13 +29,53 @@
 #include <linux/kernel.h>
 #include <linux/pci.h>
 
-#include <asm/microcode_amd.h>
 #include <asm/microcode.h>
 #include <asm/processor.h>
 #include <asm/setup.h>
 #include <asm/cpu.h>
 #include <asm/msr.h>
 
+#include "internal.h"
+
+#define UCODE_MAGIC			0x00414d44
+#define UCODE_EQUIV_CPU_TABLE_TYPE	0x00000000
+#define UCODE_UCODE_TYPE		0x00000001
+
+#define SECTION_HDR_SIZE		8
+#define CONTAINER_HDR_SZ		12
+
+struct equiv_cpu_entry {
+	u32	installed_cpu;
+	u32	fixed_errata_mask;
+	u32	fixed_errata_compare;
+	u16	equiv_cpu;
+	u16	res;
+} __packed;
+
+struct microcode_header_amd {
+	u32	data_code;
+	u32	patch_id;
+	u16	mc_patch_data_id;
+	u8	mc_patch_data_len;
+	u8	init_flag;
+	u32	mc_patch_data_checksum;
+	u32	nb_dev_id;
+	u32	sb_dev_id;
+	u16	processor_rev_id;
+	u8	nb_rev_id;
+	u8	sb_rev_id;
+	u8	bios_api_rev;
+	u8	reserved1[3];
+	u32	match_reg[8];
+} __packed;
+
+struct microcode_amd {
+	struct microcode_header_amd	hdr;
+	unsigned int			mpb[];
+};
+
+#define PATCH_MAX_SIZE (3 * PAGE_SIZE)
+
 static struct equiv_cpu_table {
 	unsigned int num_entries;
 	struct equiv_cpu_entry *entry;
@@ -56,9 +96,6 @@ struct cont_desc {
 
 static u32 ucode_new_rev;
 
-/* One blob per node. */
-static u8 amd_ucode_patch[MAX_NUMNODES][PATCH_MAX_SIZE];
-
 /*
  * Microcode patch container file is prepended to the initrd in cpio
  * format. See Documentation/arch/x86/microcode.rst
@@ -415,20 +452,17 @@ static int __apply_microcode_amd(struct microcode_amd *mc)
  *
  * Returns true if container found (sets @desc), false otherwise.
  */
-static bool early_apply_microcode(u32 cpuid_1_eax, void *ucode, size_t size, bool save_patch)
+static bool early_apply_microcode(u32 cpuid_1_eax, void *ucode, size_t size)
 {
 	struct cont_desc desc = { 0 };
-	u8 (*patch)[PATCH_MAX_SIZE];
 	struct microcode_amd *mc;
 	u32 rev, dummy, *new_rev;
 	bool ret = false;
 
 #ifdef CONFIG_X86_32
 	new_rev = (u32 *)__pa_nodebug(&ucode_new_rev);
-	patch	= (u8 (*)[PATCH_MAX_SIZE])__pa_nodebug(&amd_ucode_patch);
 #else
 	new_rev = &ucode_new_rev;
-	patch	= &amd_ucode_patch[0];
 #endif
 
 	desc.cpuid_1_eax = cpuid_1_eax;
@@ -452,9 +486,6 @@ static bool early_apply_microcode(u32 cpuid_1_eax, void *ucode, size_t size, boo
 	if (!__apply_microcode_amd(mc)) {
 		*new_rev = mc->hdr.patch_id;
 		ret      = true;
-
-		if (save_patch)
-			memcpy(patch, mc, min_t(u32, desc.psize, PATCH_MAX_SIZE));
 	}
 
 	return ret;
@@ -507,7 +538,7 @@ static void find_blobs_in_containers(unsigned int cpuid_1_eax, struct cpio_data
 	*ret = cp;
 }
 
-void __init load_ucode_amd_bsp(unsigned int cpuid_1_eax)
+static void apply_ucode_from_containers(unsigned int cpuid_1_eax)
 {
 	struct cpio_data cp = { };
 
@@ -515,42 +546,12 @@ void __init load_ucode_amd_bsp(unsigned int cpuid_1_eax)
 	if (!(cp.data && cp.size))
 		return;
 
-	early_apply_microcode(cpuid_1_eax, cp.data, cp.size, true);
+	early_apply_microcode(cpuid_1_eax, cp.data, cp.size);
 }
 
-void load_ucode_amd_ap(unsigned int cpuid_1_eax)
+void load_ucode_amd_early(unsigned int cpuid_1_eax)
 {
-	struct microcode_amd *mc;
-	struct cpio_data cp;
-	u32 *new_rev, rev, dummy;
-
-	if (IS_ENABLED(CONFIG_X86_32)) {
-		mc	= (struct microcode_amd *)__pa_nodebug(amd_ucode_patch);
-		new_rev = (u32 *)__pa_nodebug(&ucode_new_rev);
-	} else {
-		mc	= (struct microcode_amd *)amd_ucode_patch;
-		new_rev = &ucode_new_rev;
-	}
-
-	native_rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
-
-	/*
-	 * Check whether a new patch has been saved already. Also, allow application of
-	 * the same revision in order to pick up SMT-thread-specific configuration even
-	 * if the sibling SMT thread already has an up-to-date revision.
-	 */
-	if (*new_rev && rev <= mc->hdr.patch_id) {
-		if (!__apply_microcode_amd(mc)) {
-			*new_rev = mc->hdr.patch_id;
-			return;
-		}
-	}
-
-	find_blobs_in_containers(cpuid_1_eax, &cp);
-	if (!(cp.data && cp.size))
-		return;
-
-	early_apply_microcode(cpuid_1_eax, cp.data, cp.size, false);
+	return apply_ucode_from_containers(cpuid_1_eax);
 }
 
 static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size);
@@ -578,23 +579,6 @@ int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax)
 	return 0;
 }
 
-void reload_ucode_amd(unsigned int cpu)
-{
-	u32 rev, dummy __always_unused;
-	struct microcode_amd *mc;
-
-	mc = (struct microcode_amd *)amd_ucode_patch[cpu_to_node(cpu)];
-
-	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
-
-	if (rev < mc->hdr.patch_id) {
-		if (!__apply_microcode_amd(mc)) {
-			ucode_new_rev = mc->hdr.patch_id;
-			pr_info("reload patch_level=0x%08x\n", ucode_new_rev);
-		}
-	}
-}
-
 /*
  * a small, trivial cache of per-family ucode patches
  */
@@ -655,6 +639,28 @@ static struct ucode_patch *find_patch(unsigned int cpu)
 	return cache_find_patch(equiv_id);
 }
 
+void reload_ucode_amd(unsigned int cpu)
+{
+	u32 rev, dummy __always_unused;
+	struct microcode_amd *mc;
+	struct ucode_patch *p;
+
+	p = find_patch(cpu);
+	if (!p)
+		return;
+
+	mc = p->data;
+
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
+
+	if (rev < mc->hdr.patch_id) {
+		if (!__apply_microcode_amd(mc)) {
+			ucode_new_rev = mc->hdr.patch_id;
+			pr_info("reload patch_level=0x%08x\n", ucode_new_rev);
+		}
+	}
+}
+
 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -875,9 +881,6 @@ static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t siz
 			continue;
 
 		ret = UCODE_NEW;
-
-		memset(&amd_ucode_patch[nid], 0, PATCH_MAX_SIZE);
-		memcpy(&amd_ucode_patch[nid], p->data, min_t(u32, p->size, PATCH_MAX_SIZE));
 	}
 
 	return ret;
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 3afcf3de0dd4..6cc7a2c181da 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -31,15 +31,14 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 
-#include <asm/microcode_intel.h>
 #include <asm/cpu_device_id.h>
-#include <asm/microcode_amd.h>
 #include <asm/perf_event.h>
-#include <asm/microcode.h>
 #include <asm/processor.h>
 #include <asm/cmdline.h>
 #include <asm/setup.h>
 
+#include "internal.h"
+
 #define DRIVER_VERSION	"2.2"
 
 static struct microcode_ops	*microcode_ops;
@@ -54,15 +53,12 @@ LIST_HEAD(microcode_cache);
  *
  * All non cpu-hotplug-callback call sites use:
  *
- * - microcode_mutex to synchronize with each other;
  * - cpus_read_lock/unlock() to synchronize with
  *   the cpu-hotplug-callback call sites.
  *
  * We guarantee that only a single cpu is being
  * updated at any particular moment of time.
  */
-static DEFINE_MUTEX(microcode_mutex);
-
 struct ucode_cpu_info		ucode_cpu_info[NR_CPUS];
 
 struct cpu_info_ctx {
@@ -172,7 +168,7 @@ void __init load_ucode_bsp(void)
 	if (intel)
 		load_ucode_intel_bsp();
 	else
-		load_ucode_amd_bsp(cpuid_1_eax);
+		load_ucode_amd_early(cpuid_1_eax);
 }
 
 static bool check_loader_disabled_ap(void)
@@ -200,7 +196,7 @@ void load_ucode_ap(void)
 		break;
 	case X86_VENDOR_AMD:
 		if (x86_family(cpuid_1_eax) >= 0x10)
-			load_ucode_amd_ap(cpuid_1_eax);
+			load_ucode_amd_early(cpuid_1_eax);
 		break;
 	default:
 		break;
@@ -298,7 +294,7 @@ struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
 #endif
 }
 
-void reload_early_microcode(unsigned int cpu)
+static void reload_early_microcode(unsigned int cpu)
 {
 	int vendor, family;
 
@@ -488,10 +484,7 @@ static ssize_t reload_store(struct device *dev,
 	if (tmp_ret != UCODE_NEW)
 		goto put;
 
-	mutex_lock(&microcode_mutex);
 	ret = microcode_reload_late();
-	mutex_unlock(&microcode_mutex);
-
 put:
 	cpus_read_unlock();
 
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 467cf37ea90a..94dd6af9c963 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -10,15 +10,7 @@
  * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
  *		      H Peter Anvin" <hpa@zytor.com>
  */
-
-/*
- * This needs to be before all headers so that pr_debug in printk.h doesn't turn
- * printk calls into no_printk().
- *
- *#define DEBUG
- */
 #define pr_fmt(fmt) "microcode: " fmt
-
 #include <linux/earlycpio.h>
 #include <linux/firmware.h>
 #include <linux/uaccess.h>
@@ -30,13 +22,14 @@
 #include <linux/uio.h>
 #include <linux/mm.h>
 
-#include <asm/microcode_intel.h>
 #include <asm/intel-family.h>
 #include <asm/processor.h>
 #include <asm/tlbflush.h>
 #include <asm/setup.h>
 #include <asm/msr.h>
 
+#include "internal.h"
+
 static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
 
 /* Current microcode patch used in early patching on the APs. */
@@ -45,6 +38,208 @@ static struct microcode_intel *intel_ucode_patch;
 /* last level cache size per core */
 static int llc_size_per_core;
 
+/* microcode format is extended from prescott processors */
+struct extended_signature {
+	unsigned int	sig;
+	unsigned int	pf;
+	unsigned int	cksum;
+};
+
+struct extended_sigtable {
+	unsigned int			count;
+	unsigned int			cksum;
+	unsigned int			reserved[3];
+	struct extended_signature	sigs[];
+};
+
+#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
+#define EXT_HEADER_SIZE		(sizeof(struct extended_sigtable))
+#define EXT_SIGNATURE_SIZE	(sizeof(struct extended_signature))
+
+static inline unsigned int get_totalsize(struct microcode_header_intel *hdr)
+{
+	return hdr->datasize ? hdr->totalsize : DEFAULT_UCODE_TOTALSIZE;
+}
+
+static inline unsigned int exttable_size(struct extended_sigtable *et)
+{
+	return et->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE;
+}
+
+int intel_cpu_collect_info(struct ucode_cpu_info *uci)
+{
+	unsigned int val[2];
+	unsigned int family, model;
+	struct cpu_signature csig = { 0 };
+	unsigned int eax, ebx, ecx, edx;
+
+	memset(uci, 0, sizeof(*uci));
+
+	eax = 0x00000001;
+	ecx = 0;
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+	csig.sig = eax;
+
+	family = x86_family(eax);
+	model  = x86_model(eax);
+
+	if (model >= 5 || family > 6) {
+		/* get processor flags from MSR 0x17 */
+		native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
+		csig.pf = 1 << ((val[1] >> 18) & 7);
+	}
+
+	csig.rev = intel_get_microcode_revision();
+
+	uci->cpu_sig = csig;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_cpu_collect_info);
+
+/*
+ * Returns 1 if update has been found, 0 otherwise.
+ */
+int intel_find_matching_signature(void *mc, unsigned int csig, int cpf)
+{
+	struct microcode_header_intel *mc_hdr = mc;
+	struct extended_sigtable *ext_hdr;
+	struct extended_signature *ext_sig;
+	int i;
+
+	if (intel_cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
+		return 1;
+
+	/* Look for ext. headers: */
+	if (get_totalsize(mc_hdr) <= intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE)
+		return 0;
+
+	ext_hdr = mc + intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE;
+	ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
+
+	for (i = 0; i < ext_hdr->count; i++) {
+		if (intel_cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
+			return 1;
+		ext_sig++;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_find_matching_signature);
+
+/**
+ * intel_microcode_sanity_check() - Sanity check microcode file.
+ * @mc: Pointer to the microcode file contents.
+ * @print_err: Display failure reason if true, silent if false.
+ * @hdr_type: Type of file, i.e. normal microcode file or In Field Scan file.
+ *            Validate if the microcode header type matches with the type
+ *            specified here.
+ *
+ * Validate certain header fields and verify if computed checksum matches
+ * with the one specified in the header.
+ *
+ * Return: 0 if the file passes all the checks, -EINVAL if any of the checks
+ * fail.
+ */
+int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type)
+{
+	unsigned long total_size, data_size, ext_table_size;
+	struct microcode_header_intel *mc_header = mc;
+	struct extended_sigtable *ext_header = NULL;
+	u32 sum, orig_sum, ext_sigcount = 0, i;
+	struct extended_signature *ext_sig;
+
+	total_size = get_totalsize(mc_header);
+	data_size = intel_microcode_get_datasize(mc_header);
+
+	if (data_size + MC_HEADER_SIZE > total_size) {
+		if (print_err)
+			pr_err("Error: bad microcode data file size.\n");
+		return -EINVAL;
+	}
+
+	if (mc_header->ldrver != 1 || mc_header->hdrver != hdr_type) {
+		if (print_err)
+			pr_err("Error: invalid/unknown microcode update format. Header type %d\n",
+			       mc_header->hdrver);
+		return -EINVAL;
+	}
+
+	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
+	if (ext_table_size) {
+		u32 ext_table_sum = 0;
+		u32 *ext_tablep;
+
+		if (ext_table_size < EXT_HEADER_SIZE ||
+		    ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
+			if (print_err)
+				pr_err("Error: truncated extended signature table.\n");
+			return -EINVAL;
+		}
+
+		ext_header = mc + MC_HEADER_SIZE + data_size;
+		if (ext_table_size != exttable_size(ext_header)) {
+			if (print_err)
+				pr_err("Error: extended signature table size mismatch.\n");
+			return -EFAULT;
+		}
+
+		ext_sigcount = ext_header->count;
+
+		/*
+		 * Check extended table checksum: the sum of all dwords that
+		 * comprise a valid table must be 0.
+		 */
+		ext_tablep = (u32 *)ext_header;
+
+		i = ext_table_size / sizeof(u32);
+		while (i--)
+			ext_table_sum += ext_tablep[i];
+
+		if (ext_table_sum) {
+			if (print_err)
+				pr_warn("Bad extended signature table checksum, aborting.\n");
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * Calculate the checksum of update data and header. The checksum of
+	 * valid update data and header including the extended signature table
+	 * must be 0.
+	 */
+	orig_sum = 0;
+	i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
+	while (i--)
+		orig_sum += ((u32 *)mc)[i];
+
+	if (orig_sum) {
+		if (print_err)
+			pr_err("Bad microcode data checksum, aborting.\n");
+		return -EINVAL;
+	}
+
+	if (!ext_table_size)
+		return 0;
+
+	/*
+	 * Check extended signature checksum: 0 => valid.
+	 */
+	for (i = 0; i < ext_sigcount; i++) {
+		ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
+			  EXT_SIGNATURE_SIZE * i;
+
+		sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
+		      (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
+		if (sum) {
+			if (print_err)
+				pr_err("Bad extended signature checksum, aborting.\n");
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
+
 /*
  * Returns 1 if update has been found, 0 otherwise.
  */
@@ -202,86 +397,6 @@ next:
 	return patch;
 }
 
-static void show_saved_mc(void)
-{
-#ifdef DEBUG
-	int i = 0, j;
-	unsigned int sig, pf, rev, total_size, data_size, date;
-	struct ucode_cpu_info uci;
-	struct ucode_patch *p;
-
-	if (list_empty(&microcode_cache)) {
-		pr_debug("no microcode data saved.\n");
-		return;
-	}
-
-	intel_cpu_collect_info(&uci);
-
-	sig	= uci.cpu_sig.sig;
-	pf	= uci.cpu_sig.pf;
-	rev	= uci.cpu_sig.rev;
-	pr_debug("CPU: sig=0x%x, pf=0x%x, rev=0x%x\n", sig, pf, rev);
-
-	list_for_each_entry(p, &microcode_cache, plist) {
-		struct microcode_header_intel *mc_saved_header;
-		struct extended_sigtable *ext_header;
-		struct extended_signature *ext_sig;
-		int ext_sigcount;
-
-		mc_saved_header = (struct microcode_header_intel *)p->data;
-
-		sig	= mc_saved_header->sig;
-		pf	= mc_saved_header->pf;
-		rev	= mc_saved_header->rev;
-		date	= mc_saved_header->date;
-
-		total_size	= get_totalsize(mc_saved_header);
-		data_size	= get_datasize(mc_saved_header);
-
-		pr_debug("mc_saved[%d]: sig=0x%x, pf=0x%x, rev=0x%x, total size=0x%x, date = %04x-%02x-%02x\n",
-			 i++, sig, pf, rev, total_size,
-			 date & 0xffff,
-			 date >> 24,
-			 (date >> 16) & 0xff);
-
-		/* Look for ext. headers: */
-		if (total_size <= data_size + MC_HEADER_SIZE)
-			continue;
-
-		ext_header = (void *)mc_saved_header + data_size + MC_HEADER_SIZE;
-		ext_sigcount = ext_header->count;
-		ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
-
-		for (j = 0; j < ext_sigcount; j++) {
-			sig = ext_sig->sig;
-			pf = ext_sig->pf;
-
-			pr_debug("\tExtended[%d]: sig=0x%x, pf=0x%x\n",
-				 j, sig, pf);
-
-			ext_sig++;
-		}
-	}
-#endif
-}
-
-/*
- * Save this microcode patch. It will be loaded early when a CPU is
- * hot-added or resumes.
- */
-static void save_mc_for_early(struct ucode_cpu_info *uci, u8 *mc, unsigned int size)
-{
-	/* Synchronization during CPU hotplug. */
-	static DEFINE_MUTEX(x86_cpu_microcode_mutex);
-
-	mutex_lock(&x86_cpu_microcode_mutex);
-
-	save_microcode_patch(uci, mc, size);
-	show_saved_mc();
-
-	mutex_unlock(&x86_cpu_microcode_mutex);
-}
-
 static bool load_builtin_intel_microcode(struct cpio_data *cp)
 {
 	unsigned int eax = 1, ebx, ecx = 0, edx;
@@ -428,9 +543,6 @@ int __init save_microcode_in_initrd_intel(void)
 	intel_cpu_collect_info(&uci);
 
 	scan_microcode(cp.data, cp.size, &uci, true);
-
-	show_saved_mc();
-
 	return 0;
 }
 
@@ -701,12 +813,8 @@ static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
 	vfree(uci->mc);
 	uci->mc = (struct microcode_intel *)new_mc;
 
-	/*
-	 * If early loading microcode is supported, save this mc into
-	 * permanent memory. So it will be loaded early when a CPU is hot added
-	 * or resumes.
-	 */
-	save_mc_for_early(uci, new_mc, new_mc_size);
+	/* Save for CPU hotplug */
+	save_microcode_patch(uci, new_mc, new_mc_size);
 
 	pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
 		 cpu, new_rev, uci->cpu_sig.rev);
diff --git a/arch/x86/kernel/cpu/microcode/internal.h b/arch/x86/kernel/cpu/microcode/internal.h
new file mode 100644
index 000000000000..bf883aa71233
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/internal.h
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_MICROCODE_INTERNAL_H
+#define _X86_MICROCODE_INTERNAL_H
+
+#include <linux/earlycpio.h>
+#include <linux/initrd.h>
+
+#include <asm/cpu.h>
+#include <asm/microcode.h>
+
+struct ucode_patch {
+	struct list_head plist;
+	void *data;		/* Intel uses only this one */
+	unsigned int size;
+	u32 patch_id;
+	u16 equiv_cpu;
+};
+
+extern struct list_head microcode_cache;
+
+struct device;
+
+enum ucode_state {
+	UCODE_OK	= 0,
+	UCODE_NEW,
+	UCODE_UPDATED,
+	UCODE_NFOUND,
+	UCODE_ERROR,
+};
+
+struct microcode_ops {
+	enum ucode_state (*request_microcode_fw)(int cpu, struct device *dev);
+
+	void (*microcode_fini_cpu)(int cpu);
+
+	/*
+	 * The generic 'microcode_core' part guarantees that
+	 * the callbacks below run on a target cpu when they
+	 * are being called.
+	 * See also the "Synchronization" section in microcode_core.c.
+	 */
+	enum ucode_state (*apply_microcode)(int cpu);
+	int (*collect_cpu_info)(int cpu, struct cpu_signature *csig);
+};
+
+extern struct ucode_cpu_info ucode_cpu_info[];
+struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);
+
+#define MAX_UCODE_COUNT 128
+
+#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
+#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
+#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
+#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
+#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
+#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
+#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
+
+#define CPUID_IS(a, b, c, ebx, ecx, edx)	\
+		(!(((ebx) ^ (a)) | ((edx) ^ (b)) | ((ecx) ^ (c))))
+
+/*
+ * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
+ * x86_cpuid_vendor() gets vendor id for BSP.
+ *
+ * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
+ * coding, we still use x86_cpuid_vendor() to get vendor id for AP.
+ *
+ * x86_cpuid_vendor() gets vendor information directly from CPUID.
+ */
+static inline int x86_cpuid_vendor(void)
+{
+	u32 eax = 0x00000000;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
+		return X86_VENDOR_INTEL;
+
+	if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
+		return X86_VENDOR_AMD;
+
+	return X86_VENDOR_UNKNOWN;
+}
+
+static inline unsigned int x86_cpuid_family(void)
+{
+	u32 eax = 0x00000001;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	return x86_family(eax);
+}
+
+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);
+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; }
+static inline void exit_amd_microcode(void) { }
+#endif /* !CONFIG_CPU_SUP_AMD */
+
+#ifdef CONFIG_CPU_SUP_INTEL
+void load_ucode_intel_bsp(void);
+void load_ucode_intel_ap(void);
+int save_microcode_in_initrd_intel(void);
+void reload_ucode_intel(void);
+struct microcode_ops *init_intel_microcode(void);
+#else /* CONFIG_CPU_SUP_INTEL */
+static inline void load_ucode_intel_bsp(void) { }
+static inline void load_ucode_intel_ap(void) { }
+static inline int save_microcode_in_initrd_intel(void) { return -EINVAL; }
+static inline void reload_ucode_intel(void) { }
+static inline struct microcode_ops *init_intel_microcode(void) { return NULL; }
+#endif  /* !CONFIG_CPU_SUP_INTEL */
+
+#endif /* _X86_MICROCODE_INTERNAL_H */