Merge branch 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 microcode changes from Ingo Molnar:
 "Microcode driver updates: mostly cleanups but also some fixes
  (Borislav Petkov)"

* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/amd: Drop the pci_ids.h dependency
  x86/microcode/intel: Fix printing of microcode blobs in show_saved_mc()
  x86/microcode/intel: Check scan_microcode()'s retval
  x86/microcode/intel: Sanitize microcode_pointer()
  x86/microcode/intel: Move mc arg last in get_matching_{microcode|sig}
  x86/microcode/intel: Simplify generic_load_microcode_early()
  x86/microcode: Consolidate family,model, ... code
  x86/microcode/intel: Rename update_match_revision()
  x86/microcode/intel: Sanitize _save_mc()
  x86/microcode/intel: Make _save_mc() return the updated saved count
  x86/microcode/intel: Simplify load_ucode_intel_bsp()
  x86/microcode/intel: Get rid of last arg to load_ucode_intel_bsp()
  x86/microcode/intel: Do the mc_saved_src NULL check first
  x86/microcode/intel: Check if microcode was found before applying
  x86/microcode/intel: Fix out of bounds memory access to the extended header

7 files changed, 259 insertions, 274 deletions

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 201b520521ed..2fb20d6f7e23 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -75,6 +75,79 @@ static inline void __exit exit_amd_microcode(void) {}
 
 #ifdef CONFIG_MICROCODE_EARLY
 #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_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_vendor() to get vendor id for AP.
+ *
+ * x86_vendor() gets vendor information directly from CPUID.
+ */
+static inline int x86_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_family(unsigned int sig)
+{
+        unsigned int x86;
+
+        x86 = (sig >> 8) & 0xf;
+
+        if (x86 == 0xf)
+                x86 += (sig >> 20) & 0xff;
+
+        return x86;
+}
+
+static inline unsigned int x86_family(void)
+{
+        u32 eax = 0x00000001;
+        u32 ebx, ecx = 0, edx;
+
+        native_cpuid(&eax, &ebx, &ecx, &edx);
+
+        return __x86_family(eax);
+}
+
+static inline unsigned int x86_model(unsigned int sig)
+{
+        unsigned int x86, model;
+
+        x86 = __x86_family(sig);
+
+        model = (sig >> 4) & 0xf;
+
+        if (x86 == 0x6 || x86 == 0xf)
+                model += ((sig >> 16) & 0xf) << 4;
+
+        return model;
+}
+
 extern void __init load_ucode_bsp(void);
 extern void load_ucode_ap(void);
 extern int __init save_microcode_in_initrd(void);
diff --git a/arch/x86/include/asm/microcode_intel.h b/arch/x86/include/asm/microcode_intel.h
index dd4c20043ce7..2b9209c46ca9 100644
--- a/arch/x86/include/asm/microcode_intel.h
+++ b/arch/x86/include/asm/microcode_intel.h
@@ -56,12 +56,15 @@ struct extended_sigtable {
 
 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
 
-extern int
-get_matching_microcode(unsigned int csig, int cpf, void *mc, int rev);
+extern int get_matching_microcode(unsigned int csig, int cpf, int rev, void *mc);
 extern int microcode_sanity_check(void *mc, int print_err);
-extern int get_matching_sig(unsigned int csig, int cpf, void *mc, int rev);
-extern int
-update_match_revision(struct microcode_header_intel *mc_header, int rev);
+extern int get_matching_sig(unsigned int csig, int cpf, int rev, void *mc);
+
+static inline int
+revision_is_newer(struct microcode_header_intel *mc_header, int rev)
+{
+        return (mc_header->rev <= rev) ? 0 : 1;
+}
 
 #ifdef CONFIG_MICROCODE_INTEL_EARLY
 extern void __init load_ucode_intel_bsp(void);
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index bfbbe6195e2d..12829c3ced3c 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -21,7 +21,6 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/firmware.h>
-#include <linux/pci_ids.h>
 #include <linux/uaccess.h>
 #include <linux/vmalloc.h>
 #include <linux/kernel.h>
diff --git a/arch/x86/kernel/cpu/microcode/core_early.c b/arch/x86/kernel/cpu/microcode/core_early.c
index d45df4bd16ab..a413a69cbd74 100644
--- a/arch/x86/kernel/cpu/microcode/core_early.c
+++ b/arch/x86/kernel/cpu/microcode/core_early.c
@@ -23,57 +23,6 @@
 #include <asm/processor.h>
 #include <asm/cmdline.h>
 
-#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_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_vendor() to get vendor id for AP.
- *
- * x86_vendor() gets vendor information directly through cpuid.
- */
-static int x86_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 int x86_family(void)
-{
-        u32 eax = 0x00000001;
-        u32 ebx, ecx = 0, edx;
-        int x86;
-
-        native_cpuid(&eax, &ebx, &ecx, &edx);
-
-        x86 = (eax >> 8) & 0xf;
-        if (x86 == 15)
-                x86 += (eax >> 20) & 0xff;
-
-        return x86;
-}
-
 static bool __init check_loader_disabled_bsp(void)
 {
 #ifdef CONFIG_X86_32
@@ -96,7 +45,7 @@ static bool __init check_loader_disabled_bsp(void)
 
 void __init load_ucode_bsp(void)
 {
-        int vendor, x86;
+        int vendor, family;
 
         if (check_loader_disabled_bsp())
                 return;
@@ -105,15 +54,15 @@ void __init load_ucode_bsp(void)
                 return;
 
         vendor = x86_vendor();
-        x86 = x86_family();
+        family = x86_family();
 
         switch (vendor) {
         case X86_VENDOR_INTEL:
-                if (x86 >= 6)
+                if (family >= 6)
                         load_ucode_intel_bsp();
                 break;
         case X86_VENDOR_AMD:
-                if (x86 >= 0x10)
+                if (family >= 0x10)
                         load_ucode_amd_bsp();
                 break;
         default:
@@ -132,7 +81,7 @@ static bool check_loader_disabled_ap(void)
 
 void load_ucode_ap(void)
 {
-        int vendor, x86;
+        int vendor, family;
 
         if (check_loader_disabled_ap())
                 return;
@@ -141,15 +90,15 @@ void load_ucode_ap(void)
                 return;
 
         vendor = x86_vendor();
-        x86 = x86_family();
+        family = x86_family();
 
         switch (vendor) {
         case X86_VENDOR_INTEL:
-                if (x86 >= 6)
+                if (family >= 6)
                         load_ucode_intel_ap();
                 break;
         case X86_VENDOR_AMD:
-                if (x86 >= 0x10)
+                if (family >= 0x10)
                         load_ucode_amd_ap();
                 break;
         default:
@@ -179,18 +128,18 @@ int __init save_microcode_in_initrd(void)
 
 void reload_early_microcode(void)
 {
-        int vendor, x86;
+        int vendor, family;
 
         vendor = x86_vendor();
-        x86 = x86_family();
+        family = x86_family();
 
         switch (vendor) {
         case X86_VENDOR_INTEL:
-                if (x86 >= 6)
+                if (family >= 6)
                         reload_ucode_intel();
                 break;
         case X86_VENDOR_AMD:
-                if (x86 >= 0x10)
+                if (family >= 0x10)
                         reload_ucode_amd();
                 break;
         default:
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 746e7fd08aad..a41beadb3db9 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -124,7 +124,7 @@ static int get_matching_mc(struct microcode_intel *mc_intel, int cpu)
         cpf = cpu_sig.pf;
         crev = cpu_sig.rev;
 
-        return get_matching_microcode(csig, cpf, mc_intel, crev);
+        return get_matching_microcode(csig, cpf, crev, mc_intel);
 }
 
 static int apply_microcode_intel(int cpu)
@@ -226,7 +226,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 
                 csig = uci->cpu_sig.sig;
                 cpf = uci->cpu_sig.pf;
-                if (get_matching_microcode(csig, cpf, mc, new_rev)) {
+                if (get_matching_microcode(csig, cpf, new_rev, mc)) {
                         vfree(new_mc);
                         new_rev = mc_header.rev;
                         new_mc  = mc;
diff --git a/arch/x86/kernel/cpu/microcode/intel_early.c b/arch/x86/kernel/cpu/microcode/intel_early.c
index 420eb933189c..2f49ab4ac0ae 100644
--- a/arch/x86/kernel/cpu/microcode/intel_early.c
+++ b/arch/x86/kernel/cpu/microcode/intel_early.c
@@ -16,6 +16,14 @@
  *      as published by the Free Software Foundation; either version
  *      2 of the License, or (at your option) any later version.
  */
+
+/*
+ * This needs to be before all headers so that pr_debug in printk.h doesn't turn
+ * printk calls into no_printk().
+ *
+ *#define DEBUG
+ */
+
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
@@ -28,6 +36,9 @@
 #include <asm/tlbflush.h>
 #include <asm/setup.h>
 
+#undef pr_fmt
+#define pr_fmt(fmt)     "microcode: " fmt
+
 static unsigned long mc_saved_in_initrd[MAX_UCODE_COUNT];
 static struct mc_saved_data {
         unsigned int mc_saved_count;
@@ -35,50 +46,45 @@ static struct mc_saved_data {
 } mc_saved_data;
 
 static enum ucode_state
-generic_load_microcode_early(struct microcode_intel **mc_saved_p,
-                             unsigned int mc_saved_count,
-                             struct ucode_cpu_info *uci)
+load_microcode_early(struct microcode_intel **saved,
+                     unsigned int num_saved, struct ucode_cpu_info *uci)
 {
         struct microcode_intel *ucode_ptr, *new_mc = NULL;
-        int new_rev = uci->cpu_sig.rev;
-        enum ucode_state state = UCODE_OK;
-        unsigned int mc_size;
-        struct microcode_header_intel *mc_header;
-        unsigned int csig = uci->cpu_sig.sig;
-        unsigned int cpf = uci->cpu_sig.pf;
-        int i;
+        struct microcode_header_intel *mc_hdr;
+        int new_rev, ret, i;
 
-        for (i = 0; i < mc_saved_count; i++) {
-                ucode_ptr = mc_saved_p[i];
+        new_rev = uci->cpu_sig.rev;
 
-                mc_header = (struct microcode_header_intel *)ucode_ptr;
-                mc_size = get_totalsize(mc_header);
-                if (get_matching_microcode(csig, cpf, ucode_ptr, new_rev)) {
-                        new_rev = mc_header->rev;
-                        new_mc  = ucode_ptr;
-                }
-        }
+        for (i = 0; i < num_saved; i++) {
+                ucode_ptr = saved[i];
+                mc_hdr    = (struct microcode_header_intel *)ucode_ptr;
 
-        if (!new_mc) {
-                state = UCODE_NFOUND;
-                goto out;
+                ret = get_matching_microcode(uci->cpu_sig.sig,
+                                             uci->cpu_sig.pf,
+                                             new_rev,
+                                             ucode_ptr);
+                if (!ret)
+                        continue;
+
+                new_rev = mc_hdr->rev;
+                new_mc  = ucode_ptr;
         }
 
+        if (!new_mc)
+                return UCODE_NFOUND;
+
         uci->mc = (struct microcode_intel *)new_mc;
-out:
-        return state;
+        return UCODE_OK;
 }
 
-static void
-microcode_pointer(struct microcode_intel **mc_saved,
-                  unsigned long *mc_saved_in_initrd,
-                  unsigned long initrd_start, int mc_saved_count)
+static inline void
+copy_initrd_ptrs(struct microcode_intel **mc_saved, unsigned long *initrd,
+                  unsigned long off, int num_saved)
 {
         int i;
 
-        for (i = 0; i < mc_saved_count; i++)
-                mc_saved[i] = (struct microcode_intel *)
-                              (mc_saved_in_initrd[i] + initrd_start);
+        for (i = 0; i < num_saved; i++)
+                mc_saved[i] = (struct microcode_intel *)(initrd[i] + off);
 }
 
 #ifdef CONFIG_X86_32
@@ -102,55 +108,27 @@ microcode_phys(struct microcode_intel **mc_saved_tmp,
 #endif
 
 static enum ucode_state
-load_microcode(struct mc_saved_data *mc_saved_data,
-               unsigned long *mc_saved_in_initrd,
-               unsigned long initrd_start,
-               struct ucode_cpu_info *uci)
+load_microcode(struct mc_saved_data *mc_saved_data, unsigned long *initrd,
+               unsigned long initrd_start, struct ucode_cpu_info *uci)
 {
         struct microcode_intel *mc_saved_tmp[MAX_UCODE_COUNT];
         unsigned int count = mc_saved_data->mc_saved_count;
 
         if (!mc_saved_data->mc_saved) {
-                microcode_pointer(mc_saved_tmp, mc_saved_in_initrd,
-                                  initrd_start, count);
+                copy_initrd_ptrs(mc_saved_tmp, initrd, initrd_start, count);
 
-                return generic_load_microcode_early(mc_saved_tmp, count, uci);
+                return load_microcode_early(mc_saved_tmp, count, uci);
         } else {
 #ifdef CONFIG_X86_32
                 microcode_phys(mc_saved_tmp, mc_saved_data);
-                return generic_load_microcode_early(mc_saved_tmp, count, uci);
+                return load_microcode_early(mc_saved_tmp, count, uci);
 #else
-                return generic_load_microcode_early(mc_saved_data->mc_saved,
+                return load_microcode_early(mc_saved_data->mc_saved,
                                                     count, uci);
 #endif
         }
 }
 
-static u8 get_x86_family(unsigned long sig)
-{
-        u8 x86;
-
-        x86 = (sig >> 8) & 0xf;
-
-        if (x86 == 0xf)
-                x86 += (sig >> 20) & 0xff;
-
-        return x86;
-}
-
-static u8 get_x86_model(unsigned long sig)
-{
-        u8 x86, x86_model;
-
-        x86 = get_x86_family(sig);
-        x86_model = (sig >> 4) & 0xf;
-
-        if (x86 == 0x6 || x86 == 0xf)
-                x86_model += ((sig >> 16) & 0xf) << 4;
-
-        return x86_model;
-}
-
 /*
  * Given CPU signature and a microcode patch, this function finds if the
  * microcode patch has matching family and model with the CPU.
@@ -159,42 +137,40 @@ static enum ucode_state
 matching_model_microcode(struct microcode_header_intel *mc_header,
                         unsigned long sig)
 {
-        u8 x86, x86_model;
-        u8 x86_ucode, x86_model_ucode;
+        unsigned int fam, model;
+        unsigned int fam_ucode, model_ucode;
         struct extended_sigtable *ext_header;
         unsigned long total_size = get_totalsize(mc_header);
         unsigned long data_size = get_datasize(mc_header);
         int ext_sigcount, i;
         struct extended_signature *ext_sig;
 
-        x86 = get_x86_family(sig);
-        x86_model = get_x86_model(sig);
+        fam   = __x86_family(sig);
+        model = x86_model(sig);
 
-        x86_ucode = get_x86_family(mc_header->sig);
-        x86_model_ucode = get_x86_model(mc_header->sig);
+        fam_ucode   = __x86_family(mc_header->sig);
+        model_ucode = x86_model(mc_header->sig);
 
-        if (x86 == x86_ucode && x86_model == x86_model_ucode)
+        if (fam == fam_ucode && model == model_ucode)
                 return UCODE_OK;
 
         /* Look for ext. headers: */
         if (total_size <= data_size + MC_HEADER_SIZE)
                 return UCODE_NFOUND;
 
-        ext_header = (struct extended_sigtable *)
-                     mc_header + data_size + MC_HEADER_SIZE;
+        ext_header   = (void *) mc_header + data_size + MC_HEADER_SIZE;
+        ext_sig      = (void *)ext_header + EXT_HEADER_SIZE;
         ext_sigcount = ext_header->count;
-        ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 
         for (i = 0; i < ext_sigcount; i++) {
-                x86_ucode = get_x86_family(ext_sig->sig);
-                x86_model_ucode = get_x86_model(ext_sig->sig);
+                fam_ucode   = __x86_family(ext_sig->sig);
+                model_ucode = x86_model(ext_sig->sig);
 
-                if (x86 == x86_ucode && x86_model == x86_model_ucode)
+                if (fam == fam_ucode && model == model_ucode)
                         return UCODE_OK;
 
                 ext_sig++;
         }
-
         return UCODE_NFOUND;
 }
 
@@ -204,7 +180,7 @@ save_microcode(struct mc_saved_data *mc_saved_data,
                unsigned int mc_saved_count)
 {
         int i, j;
-        struct microcode_intel **mc_saved_p;
+        struct microcode_intel **saved_ptr;
         int ret;
 
         if (!mc_saved_count)
@@ -213,39 +189,45 @@ save_microcode(struct mc_saved_data *mc_saved_data,
         /*
          * Copy new microcode data.
          */
-        mc_saved_p = kmalloc(mc_saved_count*sizeof(struct microcode_intel *),
-                             GFP_KERNEL);
-        if (!mc_saved_p)
+        saved_ptr = kcalloc(mc_saved_count, sizeof(struct microcode_intel *), GFP_KERNEL);
+        if (!saved_ptr)
                 return -ENOMEM;
 
         for (i = 0; i < mc_saved_count; i++) {
-                struct microcode_intel *mc = mc_saved_src[i];
-                struct microcode_header_intel *mc_header = &mc->hdr;
-                unsigned long mc_size = get_totalsize(mc_header);
-                mc_saved_p[i] = kmalloc(mc_size, GFP_KERNEL);
-                if (!mc_saved_p[i]) {
-                        ret = -ENOMEM;
-                        goto err;
-                }
+                struct microcode_header_intel *mc_hdr;
+                struct microcode_intel *mc;
+                unsigned long size;
+
                 if (!mc_saved_src[i]) {
                         ret = -EINVAL;
                         goto err;
                 }
-                memcpy(mc_saved_p[i], mc, mc_size);
+
+                mc     = mc_saved_src[i];
+                mc_hdr = &mc->hdr;
+                size   = get_totalsize(mc_hdr);
+
+                saved_ptr[i] = kmalloc(size, GFP_KERNEL);
+                if (!saved_ptr[i]) {
+                        ret = -ENOMEM;
+                        goto err;
+                }
+
+                memcpy(saved_ptr[i], mc, size);
         }
 
         /*
          * Point to newly saved microcode.
          */
-        mc_saved_data->mc_saved = mc_saved_p;
+        mc_saved_data->mc_saved = saved_ptr;
         mc_saved_data->mc_saved_count = mc_saved_count;
 
         return 0;
 
 err:
         for (j = 0; j <= i; j++)
-                kfree(mc_saved_p[j]);
-        kfree(mc_saved_p);
+                kfree(saved_ptr[j]);
+        kfree(saved_ptr);
 
         return ret;
 }
@@ -257,48 +239,45 @@ err:
  * - or if it is a newly discovered microcode patch.
  *
  * The microcode patch should have matching model with CPU.
+ *
+ * Returns: The updated number @num_saved of saved microcode patches.
  */
-static void _save_mc(struct microcode_intel **mc_saved, u8 *ucode_ptr,
-                     unsigned int *mc_saved_count_p)
+static unsigned int _save_mc(struct microcode_intel **mc_saved,
+                             u8 *ucode_ptr, unsigned int num_saved)
 {
-        int i;
-        int found = 0;
-        unsigned int mc_saved_count = *mc_saved_count_p;
-        struct microcode_header_intel *mc_header;
+        struct microcode_header_intel *mc_hdr, *mc_saved_hdr;
+        unsigned int sig, pf, new_rev;
+        int found = 0, i;
+
+        mc_hdr = (struct microcode_header_intel *)ucode_ptr;
+
+        for (i = 0; i < num_saved; i++) {
+                mc_saved_hdr = (struct microcode_header_intel *)mc_saved[i];
+                sig          = mc_saved_hdr->sig;
+                pf           = mc_saved_hdr->pf;
+                new_rev      = mc_hdr->rev;
+
+                if (!get_matching_sig(sig, pf, new_rev, ucode_ptr))
+                        continue;
+
+                found = 1;
+
+                if (!revision_is_newer(mc_hdr, new_rev))
+                        continue;
 
-        mc_header = (struct microcode_header_intel *)ucode_ptr;
-        for (i = 0; i < mc_saved_count; i++) {
-                unsigned int sig, pf;
-                unsigned int new_rev;
-                struct microcode_header_intel *mc_saved_header =
-                             (struct microcode_header_intel *)mc_saved[i];
-                sig = mc_saved_header->sig;
-                pf = mc_saved_header->pf;
-                new_rev = mc_header->rev;
-
-                if (get_matching_sig(sig, pf, ucode_ptr, new_rev)) {
-                        found = 1;
-                        if (update_match_revision(mc_header, new_rev)) {
-                                /*
-                                 * Found an older ucode saved before.
-                                 * Replace the older one with this newer
-                                 * one.
-                                 */
-                                mc_saved[i] =
-                                        (struct microcode_intel *)ucode_ptr;
-                                break;
-                        }
-                }
-        }
-        if (i >= mc_saved_count && !found)
                 /*
-                 * This ucode is first time discovered in ucode file.
-                 * Save it to memory.
+                 * Found an older ucode saved earlier. Replace it with
+                 * this newer one.
                  */
-                mc_saved[mc_saved_count++] =
-                                 (struct microcode_intel *)ucode_ptr;
+                mc_saved[i] = (struct microcode_intel *)ucode_ptr;
+                break;
+        }
+
+        /* Newly detected microcode, save it to memory. */
+        if (i >= num_saved && !found)
+                mc_saved[num_saved++] = (struct microcode_intel *)ucode_ptr;
 
-        *mc_saved_count_p = mc_saved_count;
+        return num_saved;
 }
 
 /*
@@ -346,7 +325,7 @@ get_matching_model_microcode(int cpu, unsigned long start,
                         continue;
                 }
 
-                _save_mc(mc_saved_tmp, ucode_ptr, &mc_saved_count);
+                mc_saved_count = _save_mc(mc_saved_tmp, ucode_ptr, mc_saved_count);
 
                 ucode_ptr += mc_size;
         }
@@ -372,7 +351,7 @@ out:
 static int collect_cpu_info_early(struct ucode_cpu_info *uci)
 {
         unsigned int val[2];
-        u8 x86, x86_model;
+        unsigned int family, model;
         struct cpu_signature csig;
         unsigned int eax, ebx, ecx, edx;
 
@@ -387,10 +366,10 @@ static int collect_cpu_info_early(struct ucode_cpu_info *uci)
         native_cpuid(&eax, &ebx, &ecx, &edx);
         csig.sig = eax;
 
-        x86 = get_x86_family(csig.sig);
-        x86_model = get_x86_model(csig.sig);
+        family = __x86_family(csig.sig);
+        model  = x86_model(csig.sig);
 
-        if ((x86_model >= 5) || (x86 > 6)) {
+        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);
@@ -429,8 +408,7 @@ static void __ref show_saved_mc(void)
         sig = uci.cpu_sig.sig;
         pf = uci.cpu_sig.pf;
         rev = uci.cpu_sig.rev;
-        pr_debug("CPU%d: sig=0x%x, pf=0x%x, rev=0x%x\n",
-                 smp_processor_id(), sig, pf, rev);
+        pr_debug("CPU: sig=0x%x, pf=0x%x, rev=0x%x\n", sig, pf, rev);
 
         for (i = 0; i < mc_saved_data.mc_saved_count; i++) {
                 struct microcode_header_intel *mc_saved_header;
@@ -457,8 +435,7 @@ static void __ref show_saved_mc(void)
                 if (total_size <= data_size + MC_HEADER_SIZE)
                         continue;
 
-                ext_header = (struct extended_sigtable *)
-                             mc_saved_header + data_size + MC_HEADER_SIZE;
+                ext_header = (void *) mc_saved_header + data_size + MC_HEADER_SIZE;
                 ext_sigcount = ext_header->count;
                 ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 
@@ -515,8 +492,7 @@ int save_mc_for_early(u8 *mc)
          * Save the microcode patch mc in mc_save_tmp structure if it's a newer
          * version.
          */
-
-        _save_mc(mc_saved_tmp, mc, &mc_saved_count);
+        mc_saved_count = _save_mc(mc_saved_tmp, mc, mc_saved_count);
 
         /*
          * Save the mc_save_tmp in global mc_saved_data.
@@ -548,12 +524,10 @@ EXPORT_SYMBOL_GPL(save_mc_for_early);
 
 static __initdata char ucode_name[] = "kernel/x86/microcode/GenuineIntel.bin";
 static __init enum ucode_state
-scan_microcode(unsigned long start, unsigned long end,
-                struct mc_saved_data *mc_saved_data,
-                unsigned long *mc_saved_in_initrd,
-                struct ucode_cpu_info *uci)
+scan_microcode(struct mc_saved_data *mc_saved_data, unsigned long *initrd,
+               unsigned long start, unsigned long size,
+               struct ucode_cpu_info *uci)
 {
-        unsigned int size = end - start + 1;
         struct cpio_data cd;
         long offset = 0;
 #ifdef CONFIG_X86_32
@@ -569,10 +543,8 @@ scan_microcode(unsigned long start, unsigned long end,
         if (!cd.data)
                 return UCODE_ERROR;
 
-
         return get_matching_model_microcode(0, start, cd.data, cd.size,
-                                            mc_saved_data, mc_saved_in_initrd,
-                                            uci);
+                                            mc_saved_data, initrd, uci);
 }
 
 /*
@@ -704,7 +676,7 @@ int __init save_microcode_in_initrd_intel(void)
         if (count == 0)
                 return ret;
 
-        microcode_pointer(mc_saved, mc_saved_in_initrd, initrd_start, count);
+        copy_initrd_ptrs(mc_saved, mc_saved_in_initrd, initrd_start, count);
         ret = save_microcode(&mc_saved_data, mc_saved, count);
         if (ret)
                 pr_err("Cannot save microcode patches from initrd.\n");
@@ -716,52 +688,44 @@ int __init save_microcode_in_initrd_intel(void)
 
 static void __init
 _load_ucode_intel_bsp(struct mc_saved_data *mc_saved_data,
-                      unsigned long *mc_saved_in_initrd,
-                      unsigned long initrd_start_early,
-                      unsigned long initrd_end_early,
-                      struct ucode_cpu_info *uci)
+                      unsigned long *initrd,
+                      unsigned long start, unsigned long size)
 {
+        struct ucode_cpu_info uci;
         enum ucode_state ret;
 
-        collect_cpu_info_early(uci);
-        scan_microcode(initrd_start_early, initrd_end_early, mc_saved_data,
-                       mc_saved_in_initrd, uci);
+        collect_cpu_info_early(&uci);
 
-        ret = load_microcode(mc_saved_data, mc_saved_in_initrd,
-                             initrd_start_early, uci);
+        ret = scan_microcode(mc_saved_data, initrd, start, size, &uci);
+        if (ret != UCODE_OK)
+                return;
 
-        if (ret == UCODE_OK)
-                apply_microcode_early(uci, true);
+        ret = load_microcode(mc_saved_data, initrd, start, &uci);
+        if (ret != UCODE_OK)
+                return;
+
+        apply_microcode_early(&uci, true);
 }
 
-void __init
-load_ucode_intel_bsp(void)
+void __init load_ucode_intel_bsp(void)
 {
-        u64 ramdisk_image, ramdisk_size;
-        unsigned long initrd_start_early, initrd_end_early;
-        struct ucode_cpu_info uci;
+        u64 start, size;
 #ifdef CONFIG_X86_32
-        struct boot_params *boot_params_p;
+        struct boot_params *p;
 
-        boot_params_p = (struct boot_params *)__pa_nodebug(&boot_params);
-        ramdisk_image = boot_params_p->hdr.ramdisk_image;
-        ramdisk_size  = boot_params_p->hdr.ramdisk_size;
-        initrd_start_early = ramdisk_image;
-        initrd_end_early = initrd_start_early + ramdisk_size;
+        p       = (struct boot_params *)__pa_nodebug(&boot_params);
+        start   = p->hdr.ramdisk_image;
+        size    = p->hdr.ramdisk_size;
 
         _load_ucode_intel_bsp(
-                (struct mc_saved_data *)__pa_nodebug(&mc_saved_data),
-                (unsigned long *)__pa_nodebug(&mc_saved_in_initrd),
-                initrd_start_early, initrd_end_early, &uci);
+                        (struct mc_saved_data *)__pa_nodebug(&mc_saved_data),
+                        (unsigned long *)__pa_nodebug(&mc_saved_in_initrd),
+                        start, size);
 #else
-        ramdisk_image = boot_params.hdr.ramdisk_image;
-        ramdisk_size  = boot_params.hdr.ramdisk_size;
-        initrd_start_early = ramdisk_image + PAGE_OFFSET;
-        initrd_end_early = initrd_start_early + ramdisk_size;
-
-        _load_ucode_intel_bsp(&mc_saved_data, mc_saved_in_initrd,
-                              initrd_start_early, initrd_end_early,
-                              &uci);
+        start   = boot_params.hdr.ramdisk_image + PAGE_OFFSET;
+        size    = boot_params.hdr.ramdisk_size;
+
+        _load_ucode_intel_bsp(&mc_saved_data, mc_saved_in_initrd, start, size);
 #endif
 }
 
@@ -771,6 +735,7 @@ void load_ucode_intel_ap(void)
         struct ucode_cpu_info uci;
         unsigned long *mc_saved_in_initrd_p;
         unsigned long initrd_start_addr;
+        enum ucode_state ret;
 #ifdef CONFIG_X86_32
         unsigned long *initrd_start_p;
 
@@ -793,8 +758,12 @@ void load_ucode_intel_ap(void)
                 return;
 
         collect_cpu_info_early(&uci);
-        load_microcode(mc_saved_data_p, mc_saved_in_initrd_p,
-                       initrd_start_addr, &uci);
+        ret = load_microcode(mc_saved_data_p, mc_saved_in_initrd_p,
+                             initrd_start_addr, &uci);
+
+        if (ret != UCODE_OK)
+                return;
+
         apply_microcode_early(&uci, true);
 }
 
@@ -808,8 +777,8 @@ void reload_ucode_intel(void)
 
         collect_cpu_info_early(&uci);
 
-        ret = generic_load_microcode_early(mc_saved_data.mc_saved,
-                                           mc_saved_data.mc_saved_count, &uci);
+        ret = load_microcode_early(mc_saved_data.mc_saved,
+                                   mc_saved_data.mc_saved_count, &uci);
         if (ret != UCODE_OK)
                 return;
 
diff --git a/arch/x86/kernel/cpu/microcode/intel_lib.c b/arch/x86/kernel/cpu/microcode/intel_lib.c
index ce69320d0179..cd47a510a3f1 100644
--- a/arch/x86/kernel/cpu/microcode/intel_lib.c
+++ b/arch/x86/kernel/cpu/microcode/intel_lib.c
@@ -38,12 +38,6 @@ update_match_cpu(unsigned int csig, unsigned int cpf,
         return (!sigmatch(sig, csig, pf, cpf)) ? 0 : 1;
 }
 
-int
-update_match_revision(struct microcode_header_intel *mc_header, int rev)
-{
-        return (mc_header->rev <= rev) ? 0 : 1;
-}
-
 int microcode_sanity_check(void *mc, int print_err)
 {
         unsigned long total_size, data_size, ext_table_size;
@@ -128,10 +122,9 @@ int microcode_sanity_check(void *mc, int print_err)
 EXPORT_SYMBOL_GPL(microcode_sanity_check);
 
 /*
- * return 0 - no update found
- * return 1 - found update
+ * Returns 1 if update has been found, 0 otherwise.
  */
-int get_matching_sig(unsigned int csig, int cpf, void *mc, int rev)
+int get_matching_sig(unsigned int csig, int cpf, int rev, void *mc)
 {
         struct microcode_header_intel *mc_header = mc;
         struct extended_sigtable *ext_header;
@@ -159,16 +152,15 @@ int get_matching_sig(unsigned int csig, int cpf, void *mc, int rev)
 }
 
 /*
- * return 0 - no update found
- * return 1 - found update
+ * Returns 1 if update has been found, 0 otherwise.
  */
-int get_matching_microcode(unsigned int csig, int cpf, void *mc, int rev)
+int get_matching_microcode(unsigned int csig, int cpf, int rev, void *mc)
 {
-        struct microcode_header_intel *mc_header = mc;
+        struct microcode_header_intel *mc_hdr = mc;
 
-        if (!update_match_revision(mc_header, rev))
+        if (!revision_is_newer(mc_hdr, rev))
                 return 0;
 
-        return get_matching_sig(csig, cpf, mc, rev);
+        return get_matching_sig(csig, cpf, rev, mc);
 }
 EXPORT_SYMBOL_GPL(get_matching_microcode);