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-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c941
1 files changed, 941 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
new file mode 100644
index 000000000..1def66118
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -0,0 +1,941 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Intel CPU Microcode Update Driver for Linux
+ *
+ * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
+ * 2006 Shaohua Li <shaohua.li@intel.com>
+ *
+ * Intel CPU microcode early update for Linux
+ *
+ * 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>
+#include <linux/vmalloc.h>
+#include <linux/initrd.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#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>
+
+static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
+
+/* Current microcode patch used in early patching on the APs. */
+static struct microcode_intel *intel_ucode_patch;
+
+/* last level cache size per core */
+static int llc_size_per_core;
+
+/*
+ * Returns 1 if update has been found, 0 otherwise.
+ */
+static int 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;
+}
+
+/*
+ * Returns 1 if update has been found, 0 otherwise.
+ */
+static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
+{
+ struct microcode_header_intel *mc_hdr = mc;
+
+ if (mc_hdr->rev <= new_rev)
+ return 0;
+
+ return find_matching_signature(mc, csig, cpf);
+}
+
+static struct ucode_patch *memdup_patch(void *data, unsigned int size)
+{
+ struct ucode_patch *p;
+
+ p = kzalloc(sizeof(struct ucode_patch), GFP_KERNEL);
+ if (!p)
+ return NULL;
+
+ p->data = kmemdup(data, size, GFP_KERNEL);
+ if (!p->data) {
+ kfree(p);
+ return NULL;
+ }
+
+ return p;
+}
+
+static void save_microcode_patch(struct ucode_cpu_info *uci, void *data, unsigned int size)
+{
+ struct microcode_header_intel *mc_hdr, *mc_saved_hdr;
+ struct ucode_patch *iter, *tmp, *p = NULL;
+ bool prev_found = false;
+ unsigned int sig, pf;
+
+ mc_hdr = (struct microcode_header_intel *)data;
+
+ list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
+ mc_saved_hdr = (struct microcode_header_intel *)iter->data;
+ sig = mc_saved_hdr->sig;
+ pf = mc_saved_hdr->pf;
+
+ if (find_matching_signature(data, sig, pf)) {
+ prev_found = true;
+
+ if (mc_hdr->rev <= mc_saved_hdr->rev)
+ continue;
+
+ p = memdup_patch(data, size);
+ if (!p)
+ pr_err("Error allocating buffer %p\n", data);
+ else {
+ list_replace(&iter->plist, &p->plist);
+ kfree(iter->data);
+ kfree(iter);
+ }
+ }
+ }
+
+ /*
+ * There weren't any previous patches found in the list cache; save the
+ * newly found.
+ */
+ if (!prev_found) {
+ p = memdup_patch(data, size);
+ if (!p)
+ pr_err("Error allocating buffer for %p\n", data);
+ else
+ list_add_tail(&p->plist, &microcode_cache);
+ }
+
+ if (!p)
+ return;
+
+ if (!find_matching_signature(p->data, uci->cpu_sig.sig, uci->cpu_sig.pf))
+ return;
+
+ /*
+ * Save for early loading. On 32-bit, that needs to be a physical
+ * address as the APs are running from physical addresses, before
+ * paging has been enabled.
+ */
+ if (IS_ENABLED(CONFIG_X86_32))
+ intel_ucode_patch = (struct microcode_intel *)__pa_nodebug(p->data);
+ else
+ intel_ucode_patch = p->data;
+}
+
+static int microcode_sanity_check(void *mc, int print_err)
+{
+ 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 != 1) {
+ if (print_err)
+ pr_err("Error: invalid/unknown microcode update format.\n");
+ 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;
+}
+
+/*
+ * Get microcode matching with BSP's model. Only CPUs with the same model as
+ * BSP can stay in the platform.
+ */
+static struct microcode_intel *
+scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
+{
+ struct microcode_header_intel *mc_header;
+ struct microcode_intel *patch = NULL;
+ unsigned int mc_size;
+
+ while (size) {
+ if (size < sizeof(struct microcode_header_intel))
+ break;
+
+ mc_header = (struct microcode_header_intel *)data;
+
+ mc_size = get_totalsize(mc_header);
+ if (!mc_size ||
+ mc_size > size ||
+ microcode_sanity_check(data, 0) < 0)
+ break;
+
+ size -= mc_size;
+
+ if (!find_matching_signature(data, uci->cpu_sig.sig,
+ uci->cpu_sig.pf)) {
+ data += mc_size;
+ continue;
+ }
+
+ if (save) {
+ save_microcode_patch(uci, data, mc_size);
+ goto next;
+ }
+
+
+ if (!patch) {
+ if (!has_newer_microcode(data,
+ uci->cpu_sig.sig,
+ uci->cpu_sig.pf,
+ uci->cpu_sig.rev))
+ goto next;
+
+ } else {
+ struct microcode_header_intel *phdr = &patch->hdr;
+
+ if (!has_newer_microcode(data,
+ phdr->sig,
+ phdr->pf,
+ phdr->rev))
+ goto next;
+ }
+
+ /* We have a newer patch, save it. */
+ patch = data;
+
+next:
+ data += mc_size;
+ }
+
+ if (size)
+ return NULL;
+
+ 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;
+ struct firmware fw;
+ char name[30];
+
+ if (IS_ENABLED(CONFIG_X86_32))
+ return false;
+
+ native_cpuid(&eax, &ebx, &ecx, &edx);
+
+ sprintf(name, "intel-ucode/%02x-%02x-%02x",
+ x86_family(eax), x86_model(eax), x86_stepping(eax));
+
+ if (firmware_request_builtin(&fw, name)) {
+ cp->size = fw.size;
+ cp->data = (void *)fw.data;
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * Print ucode update info.
+ */
+static void
+print_ucode_info(struct ucode_cpu_info *uci, unsigned int date)
+{
+ pr_info_once("microcode updated early to revision 0x%x, date = %04x-%02x-%02x\n",
+ uci->cpu_sig.rev,
+ date & 0xffff,
+ date >> 24,
+ (date >> 16) & 0xff);
+}
+
+#ifdef CONFIG_X86_32
+
+static int delay_ucode_info;
+static int current_mc_date;
+
+/*
+ * Print early updated ucode info after printk works. This is delayed info dump.
+ */
+void show_ucode_info_early(void)
+{
+ struct ucode_cpu_info uci;
+
+ if (delay_ucode_info) {
+ intel_cpu_collect_info(&uci);
+ print_ucode_info(&uci, current_mc_date);
+ delay_ucode_info = 0;
+ }
+}
+
+/*
+ * At this point, we can not call printk() yet. Delay printing microcode info in
+ * show_ucode_info_early() until printk() works.
+ */
+static void print_ucode(struct ucode_cpu_info *uci)
+{
+ struct microcode_intel *mc;
+ int *delay_ucode_info_p;
+ int *current_mc_date_p;
+
+ mc = uci->mc;
+ if (!mc)
+ return;
+
+ delay_ucode_info_p = (int *)__pa_nodebug(&delay_ucode_info);
+ current_mc_date_p = (int *)__pa_nodebug(&current_mc_date);
+
+ *delay_ucode_info_p = 1;
+ *current_mc_date_p = mc->hdr.date;
+}
+#else
+
+static inline void print_ucode(struct ucode_cpu_info *uci)
+{
+ struct microcode_intel *mc;
+
+ mc = uci->mc;
+ if (!mc)
+ return;
+
+ print_ucode_info(uci, mc->hdr.date);
+}
+#endif
+
+static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
+{
+ struct microcode_intel *mc;
+ u32 rev;
+
+ mc = uci->mc;
+ if (!mc)
+ return 0;
+
+ /*
+ * Save us the MSR write below - which is a particular expensive
+ * operation - when the other hyperthread has updated the microcode
+ * already.
+ */
+ rev = intel_get_microcode_revision();
+ if (rev >= mc->hdr.rev) {
+ uci->cpu_sig.rev = rev;
+ return UCODE_OK;
+ }
+
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
+ /* write microcode via MSR 0x79 */
+ native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
+
+ rev = intel_get_microcode_revision();
+ if (rev != mc->hdr.rev)
+ return -1;
+
+ uci->cpu_sig.rev = rev;
+
+ if (early)
+ print_ucode(uci);
+ else
+ print_ucode_info(uci, mc->hdr.date);
+
+ return 0;
+}
+
+int __init save_microcode_in_initrd_intel(void)
+{
+ struct ucode_cpu_info uci;
+ struct cpio_data cp;
+
+ /*
+ * initrd is going away, clear patch ptr. We will scan the microcode one
+ * last time before jettisoning and save a patch, if found. Then we will
+ * update that pointer too, with a stable patch address to use when
+ * resuming the cores.
+ */
+ intel_ucode_patch = NULL;
+
+ if (!load_builtin_intel_microcode(&cp))
+ cp = find_microcode_in_initrd(ucode_path, false);
+
+ if (!(cp.data && cp.size))
+ return 0;
+
+ intel_cpu_collect_info(&uci);
+
+ scan_microcode(cp.data, cp.size, &uci, true);
+
+ show_saved_mc();
+
+ return 0;
+}
+
+/*
+ * @res_patch, output: a pointer to the patch we found.
+ */
+static struct microcode_intel *__load_ucode_intel(struct ucode_cpu_info *uci)
+{
+ static const char *path;
+ struct cpio_data cp;
+ bool use_pa;
+
+ if (IS_ENABLED(CONFIG_X86_32)) {
+ path = (const char *)__pa_nodebug(ucode_path);
+ use_pa = true;
+ } else {
+ path = ucode_path;
+ use_pa = false;
+ }
+
+ /* try built-in microcode first */
+ if (!load_builtin_intel_microcode(&cp))
+ cp = find_microcode_in_initrd(path, use_pa);
+
+ if (!(cp.data && cp.size))
+ return NULL;
+
+ intel_cpu_collect_info(uci);
+
+ return scan_microcode(cp.data, cp.size, uci, false);
+}
+
+void __init load_ucode_intel_bsp(void)
+{
+ struct microcode_intel *patch;
+ struct ucode_cpu_info uci;
+
+ patch = __load_ucode_intel(&uci);
+ if (!patch)
+ return;
+
+ uci.mc = patch;
+
+ apply_microcode_early(&uci, true);
+}
+
+void load_ucode_intel_ap(void)
+{
+ struct microcode_intel *patch, **iup;
+ struct ucode_cpu_info uci;
+
+ if (IS_ENABLED(CONFIG_X86_32))
+ iup = (struct microcode_intel **) __pa_nodebug(&intel_ucode_patch);
+ else
+ iup = &intel_ucode_patch;
+
+ if (!*iup) {
+ patch = __load_ucode_intel(&uci);
+ if (!patch)
+ return;
+
+ *iup = patch;
+ }
+
+ uci.mc = *iup;
+
+ apply_microcode_early(&uci, true);
+}
+
+static struct microcode_intel *find_patch(struct ucode_cpu_info *uci)
+{
+ struct microcode_header_intel *phdr;
+ struct ucode_patch *iter, *tmp;
+
+ list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
+
+ phdr = (struct microcode_header_intel *)iter->data;
+
+ if (phdr->rev <= uci->cpu_sig.rev)
+ continue;
+
+ if (!find_matching_signature(phdr,
+ uci->cpu_sig.sig,
+ uci->cpu_sig.pf))
+ continue;
+
+ return iter->data;
+ }
+ return NULL;
+}
+
+void reload_ucode_intel(void)
+{
+ struct microcode_intel *p;
+ struct ucode_cpu_info uci;
+
+ intel_cpu_collect_info(&uci);
+
+ p = find_patch(&uci);
+ if (!p)
+ return;
+
+ uci.mc = p;
+
+ apply_microcode_early(&uci, false);
+}
+
+static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
+{
+ static struct cpu_signature prev;
+ struct cpuinfo_x86 *c = &cpu_data(cpu_num);
+ unsigned int val[2];
+
+ memset(csig, 0, sizeof(*csig));
+
+ csig->sig = cpuid_eax(0x00000001);
+
+ if ((c->x86_model >= 5) || (c->x86 > 6)) {
+ /* get processor flags from MSR 0x17 */
+ rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
+ csig->pf = 1 << ((val[1] >> 18) & 7);
+ }
+
+ csig->rev = c->microcode;
+
+ /* No extra locking on prev, races are harmless. */
+ if (csig->sig != prev.sig || csig->pf != prev.pf || csig->rev != prev.rev) {
+ pr_info("sig=0x%x, pf=0x%x, revision=0x%x\n",
+ csig->sig, csig->pf, csig->rev);
+ prev = *csig;
+ }
+
+ return 0;
+}
+
+static enum ucode_state apply_microcode_intel(int cpu)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
+ bool bsp = c->cpu_index == boot_cpu_data.cpu_index;
+ struct microcode_intel *mc;
+ enum ucode_state ret;
+ static int prev_rev;
+ u32 rev;
+
+ /* We should bind the task to the CPU */
+ if (WARN_ON(raw_smp_processor_id() != cpu))
+ return UCODE_ERROR;
+
+ /* Look for a newer patch in our cache: */
+ mc = find_patch(uci);
+ if (!mc) {
+ mc = uci->mc;
+ if (!mc)
+ return UCODE_NFOUND;
+ }
+
+ /*
+ * Save us the MSR write below - which is a particular expensive
+ * operation - when the other hyperthread has updated the microcode
+ * already.
+ */
+ rev = intel_get_microcode_revision();
+ if (rev >= mc->hdr.rev) {
+ ret = UCODE_OK;
+ goto out;
+ }
+
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
+ /* write microcode via MSR 0x79 */
+ wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
+
+ rev = intel_get_microcode_revision();
+
+ if (rev != mc->hdr.rev) {
+ pr_err("CPU%d update to revision 0x%x failed\n",
+ cpu, mc->hdr.rev);
+ return UCODE_ERROR;
+ }
+
+ if (bsp && rev != prev_rev) {
+ pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n",
+ rev,
+ mc->hdr.date & 0xffff,
+ mc->hdr.date >> 24,
+ (mc->hdr.date >> 16) & 0xff);
+ prev_rev = rev;
+ }
+
+ ret = UCODE_UPDATED;
+
+out:
+ uci->cpu_sig.rev = rev;
+ c->microcode = rev;
+
+ /* Update boot_cpu_data's revision too, if we're on the BSP: */
+ if (bsp)
+ boot_cpu_data.microcode = rev;
+
+ return ret;
+}
+
+static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+ unsigned int curr_mc_size = 0, new_mc_size = 0;
+ enum ucode_state ret = UCODE_OK;
+ int new_rev = uci->cpu_sig.rev;
+ u8 *new_mc = NULL, *mc = NULL;
+ unsigned int csig, cpf;
+
+ while (iov_iter_count(iter)) {
+ struct microcode_header_intel mc_header;
+ unsigned int mc_size, data_size;
+ u8 *data;
+
+ if (!copy_from_iter_full(&mc_header, sizeof(mc_header), iter)) {
+ pr_err("error! Truncated or inaccessible header in microcode data file\n");
+ break;
+ }
+
+ mc_size = get_totalsize(&mc_header);
+ if (mc_size < sizeof(mc_header)) {
+ pr_err("error! Bad data in microcode data file (totalsize too small)\n");
+ break;
+ }
+ data_size = mc_size - sizeof(mc_header);
+ if (data_size > iov_iter_count(iter)) {
+ pr_err("error! Bad data in microcode data file (truncated file?)\n");
+ break;
+ }
+
+ /* For performance reasons, reuse mc area when possible */
+ if (!mc || mc_size > curr_mc_size) {
+ vfree(mc);
+ mc = vmalloc(mc_size);
+ if (!mc)
+ break;
+ curr_mc_size = mc_size;
+ }
+
+ memcpy(mc, &mc_header, sizeof(mc_header));
+ data = mc + sizeof(mc_header);
+ if (!copy_from_iter_full(data, data_size, iter) ||
+ microcode_sanity_check(mc, 1) < 0) {
+ break;
+ }
+
+ csig = uci->cpu_sig.sig;
+ cpf = uci->cpu_sig.pf;
+ if (has_newer_microcode(mc, csig, cpf, new_rev)) {
+ vfree(new_mc);
+ new_rev = mc_header.rev;
+ new_mc = mc;
+ new_mc_size = mc_size;
+ mc = NULL; /* trigger new vmalloc */
+ ret = UCODE_NEW;
+ }
+ }
+
+ vfree(mc);
+
+ if (iov_iter_count(iter)) {
+ vfree(new_mc);
+ return UCODE_ERROR;
+ }
+
+ if (!new_mc)
+ return UCODE_NFOUND;
+
+ 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);
+
+ pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
+ cpu, new_rev, uci->cpu_sig.rev);
+
+ return ret;
+}
+
+static bool is_blacklisted(unsigned int cpu)
+{
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+ /*
+ * Late loading on model 79 with microcode revision less than 0x0b000021
+ * and LLC size per core bigger than 2.5MB may result in a system hang.
+ * This behavior is documented in item BDF90, #334165 (Intel Xeon
+ * Processor E7-8800/4800 v4 Product Family).
+ */
+ if (c->x86 == 6 &&
+ c->x86_model == INTEL_FAM6_BROADWELL_X &&
+ c->x86_stepping == 0x01 &&
+ llc_size_per_core > 2621440 &&
+ c->microcode < 0x0b000021) {
+ pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
+ pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
+ return true;
+ }
+
+ return false;
+}
+
+static enum ucode_state request_microcode_fw(int cpu, struct device *device,
+ bool refresh_fw)
+{
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
+ const struct firmware *firmware;
+ struct iov_iter iter;
+ enum ucode_state ret;
+ struct kvec kvec;
+ char name[30];
+
+ if (is_blacklisted(cpu))
+ return UCODE_NFOUND;
+
+ sprintf(name, "intel-ucode/%02x-%02x-%02x",
+ c->x86, c->x86_model, c->x86_stepping);
+
+ if (request_firmware_direct(&firmware, name, device)) {
+ pr_debug("data file %s load failed\n", name);
+ return UCODE_NFOUND;
+ }
+
+ kvec.iov_base = (void *)firmware->data;
+ kvec.iov_len = firmware->size;
+ iov_iter_kvec(&iter, ITER_SOURCE, &kvec, 1, firmware->size);
+ ret = generic_load_microcode(cpu, &iter);
+
+ release_firmware(firmware);
+
+ return ret;
+}
+
+static struct microcode_ops microcode_intel_ops = {
+ .request_microcode_fw = request_microcode_fw,
+ .collect_cpu_info = collect_cpu_info,
+ .apply_microcode = apply_microcode_intel,
+};
+
+static int __init calc_llc_size_per_core(struct cpuinfo_x86 *c)
+{
+ u64 llc_size = c->x86_cache_size * 1024ULL;
+
+ do_div(llc_size, c->x86_max_cores);
+
+ return (int)llc_size;
+}
+
+struct microcode_ops * __init init_intel_microcode(void)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+ if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
+ cpu_has(c, X86_FEATURE_IA64)) {
+ pr_err("Intel CPU family 0x%x not supported\n", c->x86);
+ return NULL;
+ }
+
+ llc_size_per_core = calc_llc_size_per_core(c);
+
+ return &microcode_intel_ops;
+}