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

Pull x86 microcode loading update from Peter Anvin:
 "This patchset lets us update the CPU microcode very, very early in
  initialization if the BIOS fails to do so (never happens, right?)

  This is handy for dealing with things like the Atom erratum where we
  have to run without PSE because microcode loading happens too late.

  As I mentioned in the x86/mm push request it depends on that
  infrastructure but it is otherwise a standalone feature."

* 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/Kconfig: Make early microcode loading a configuration feature
  x86/mm/init.c: Copy ucode from initrd image to kernel memory
  x86/head64.c: Early update ucode in 64-bit
  x86/head_32.S: Early update ucode in 32-bit
  x86/microcode_intel_early.c: Early update ucode on Intel's CPU
  x86/tlbflush.h: Define __native_flush_tlb_global_irq_disabled()
  x86/microcode_intel_lib.c: Early update ucode on Intel's CPU
  x86/microcode_core_early.c: Define interfaces for early loading ucode
  x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on AP
  x86/common.c: Make have_cpuid_p() a global function
  x86/microcode_intel.h: Define functions and macros for early loading ucode
  x86, doc: Documentation for early microcode loading

1 files changed, 30 insertions, 168 deletions

diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 3544aed39338..5fb2cebf556b 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -79,7 +79,7 @@
 #include <linux/module.h>
 #include <linux/vmalloc.h>
 
-#include <asm/microcode.h>
+#include <asm/microcode_intel.h>
 #include <asm/processor.h>
 #include <asm/msr.h>
 
@@ -87,59 +87,6 @@ MODULE_DESCRIPTION("Microcode Update Driver");
 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
 MODULE_LICENSE("GPL");
 
-struct microcode_header_intel {
-        unsigned int            hdrver;
-        unsigned int            rev;
-        unsigned int            date;
-        unsigned int            sig;
-        unsigned int            cksum;
-        unsigned int            ldrver;
-        unsigned int            pf;
-        unsigned int            datasize;
-        unsigned int            totalsize;
-        unsigned int            reserved[3];
-};
-
-struct microcode_intel {
-        struct microcode_header_intel hdr;
-        unsigned int            bits[0];
-};
-
-/* 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[0];
-};
-
-#define DEFAULT_UCODE_DATASIZE  (2000)
-#define MC_HEADER_SIZE          (sizeof(struct microcode_header_intel))
-#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))
-#define DWSIZE                  (sizeof(u32))
-
-#define get_totalsize(mc) \
-        (((struct microcode_intel *)mc)->hdr.totalsize ? \
-         ((struct microcode_intel *)mc)->hdr.totalsize : \
-         DEFAULT_UCODE_TOTALSIZE)
-
-#define get_datasize(mc) \
-        (((struct microcode_intel *)mc)->hdr.datasize ? \
-         ((struct microcode_intel *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
-
-#define sigmatch(s1, s2, p1, p2) \
-        (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
-
-#define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
-
 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 {
         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
@@ -162,128 +109,25 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
         return 0;
 }
 
-static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
-{
-        return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
-}
-
-static inline int
-update_match_revision(struct microcode_header_intel *mc_header, int rev)
-{
-        return (mc_header->rev <= rev) ? 0 : 1;
-}
-
-static int microcode_sanity_check(void *mc)
-{
-        unsigned long total_size, data_size, ext_table_size;
-        struct microcode_header_intel *mc_header = mc;
-        struct extended_sigtable *ext_header = NULL;
-        int 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) {
-                pr_err("error! Bad data size in microcode data file\n");
-                return -EINVAL;
-        }
-
-        if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
-                pr_err("error! Unknown microcode update format\n");
-                return -EINVAL;
-        }
-        ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
-        if (ext_table_size) {
-                if ((ext_table_size < EXT_HEADER_SIZE)
-                 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
-                        pr_err("error! Small exttable size in microcode data file\n");
-                        return -EINVAL;
-                }
-                ext_header = mc + MC_HEADER_SIZE + data_size;
-                if (ext_table_size != exttable_size(ext_header)) {
-                        pr_err("error! Bad exttable size in microcode data file\n");
-                        return -EFAULT;
-                }
-                ext_sigcount = ext_header->count;
-        }
-
-        /* check extended table checksum */
-        if (ext_table_size) {
-                int ext_table_sum = 0;
-                int *ext_tablep = (int *)ext_header;
-
-                i = ext_table_size / DWSIZE;
-                while (i--)
-                        ext_table_sum += ext_tablep[i];
-                if (ext_table_sum) {
-                        pr_warning("aborting, bad extended signature table checksum\n");
-                        return -EINVAL;
-                }
-        }
-
-        /* calculate the checksum */
-        orig_sum = 0;
-        i = (MC_HEADER_SIZE + data_size) / DWSIZE;
-        while (i--)
-                orig_sum += ((int *)mc)[i];
-        if (orig_sum) {
-                pr_err("aborting, bad checksum\n");
-                return -EINVAL;
-        }
-        if (!ext_table_size)
-                return 0;
-        /* check extended signature checksum */
-        for (i = 0; i < ext_sigcount; i++) {
-                ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
-                          EXT_SIGNATURE_SIZE * i;
-                sum = orig_sum
-                        - (mc_header->sig + mc_header->pf + mc_header->cksum)
-                        + (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
-                if (sum) {
-                        pr_err("aborting, bad checksum\n");
-                        return -EINVAL;
-                }
-        }
-        return 0;
-}
-
 /*
  * return 0 - no update found
  * return 1 - found update
  */
-static int
-get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
+static int get_matching_mc(struct microcode_intel *mc_intel, int cpu)
 {
-        struct microcode_header_intel *mc_header = mc;
-        struct extended_sigtable *ext_header;
-        unsigned long total_size = get_totalsize(mc_header);
-        int ext_sigcount, i;
-        struct extended_signature *ext_sig;
-
-        if (!update_match_revision(mc_header, rev))
-                return 0;
-
-        if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
-                return 1;
+        struct cpu_signature cpu_sig;
+        unsigned int csig, cpf, crev;
 
-        /* Look for ext. headers: */
-        if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
-                return 0;
+        collect_cpu_info(cpu, &cpu_sig);
 
-        ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
-        ext_sigcount = ext_header->count;
-        ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
+        csig = cpu_sig.sig;
+        cpf = cpu_sig.pf;
+        crev = cpu_sig.rev;
 
-        for (i = 0; i < ext_sigcount; i++) {
-                if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
-                        return 1;
-                ext_sig++;
-        }
-        return 0;
+        return get_matching_microcode(csig, cpf, mc_intel, crev);
 }
 
-static int apply_microcode(int cpu)
+int apply_microcode(int cpu)
 {
         struct microcode_intel *mc_intel;
         struct ucode_cpu_info *uci;
@@ -300,6 +144,14 @@ static int apply_microcode(int cpu)
         if (mc_intel == NULL)
                 return 0;
 
+        /*
+         * Microcode on this CPU could be updated earlier. Only apply the
+         * microcode patch in mc_intel when it is newer than the one on this
+         * CPU.
+         */
+        if (get_matching_mc(mc_intel, cpu) == 0)
+                return 0;
+
         /* write microcode via MSR 0x79 */
         wrmsr(MSR_IA32_UCODE_WRITE,
               (unsigned long) mc_intel->bits,
@@ -338,6 +190,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
         unsigned int leftover = size;
         enum ucode_state state = UCODE_OK;
         unsigned int curr_mc_size = 0;
+        unsigned int csig, cpf;
 
         while (leftover) {
                 struct microcode_header_intel mc_header;
@@ -362,11 +215,13 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
                 }
 
                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
-                    microcode_sanity_check(mc) < 0) {
+                    microcode_sanity_check(mc, 1) < 0) {
                         break;
                 }
 
-                if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
+                csig = uci->cpu_sig.sig;
+                cpf = uci->cpu_sig.pf;
+                if (get_matching_microcode(csig, cpf, mc, new_rev)) {
                         vfree(new_mc);
                         new_rev = mc_header.rev;
                         new_mc  = mc;
@@ -393,6 +248,13 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
         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(new_mc);
+
         pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
                  cpu, new_rev, uci->cpu_sig.rev);
 out: