linux-stable/arch/x86/kernel/cpu/microcode/amd.c
Borislav Petkov 0399f73299 x86/microcode/amd: Do not overwrite final patch levels
A certain number of patch levels of applied microcode should not
be overwritten by the microcode loader, otherwise bad things
will happen.

Check those and abort update if the current core has one of
those final patch levels applied by the BIOS. 32-bit needs
special handling, of course.

See https://bugzilla.suse.com/show_bug.cgi?id=913996 for more
info.

Tested-by: Peter Kirchgeßner <pkirchgessner@t-online.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1444641762-9437-7-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-12 16:15:48 +02:00

539 lines
12 KiB
C

/*
* AMD CPU Microcode Update Driver for Linux
* Copyright (C) 2008-2011 Advanced Micro Devices Inc.
*
* Author: Peter Oruba <peter.oruba@amd.com>
*
* Based on work by:
* Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
*
* Maintainers:
* Andreas Herrmann <herrmann.der.user@googlemail.com>
* Borislav Petkov <bp@alien8.de>
*
* This driver allows to upgrade microcode on F10h AMD
* CPUs and later.
*
* Licensed under the terms of the GNU General Public
* License version 2. See file COPYING for details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/firmware.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <asm/microcode.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/microcode_amd.h>
MODULE_DESCRIPTION("AMD Microcode Update Driver");
MODULE_AUTHOR("Peter Oruba");
MODULE_LICENSE("GPL v2");
static struct equiv_cpu_entry *equiv_cpu_table;
struct ucode_patch {
struct list_head plist;
void *data;
u32 patch_id;
u16 equiv_cpu;
};
static LIST_HEAD(pcache);
static u16 __find_equiv_id(unsigned int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
return find_equiv_id(equiv_cpu_table, uci->cpu_sig.sig);
}
static u32 find_cpu_family_by_equiv_cpu(u16 equiv_cpu)
{
int i = 0;
BUG_ON(!equiv_cpu_table);
while (equiv_cpu_table[i].equiv_cpu != 0) {
if (equiv_cpu == equiv_cpu_table[i].equiv_cpu)
return equiv_cpu_table[i].installed_cpu;
i++;
}
return 0;
}
/*
* a small, trivial cache of per-family ucode patches
*/
static struct ucode_patch *cache_find_patch(u16 equiv_cpu)
{
struct ucode_patch *p;
list_for_each_entry(p, &pcache, plist)
if (p->equiv_cpu == equiv_cpu)
return p;
return NULL;
}
static void update_cache(struct ucode_patch *new_patch)
{
struct ucode_patch *p;
list_for_each_entry(p, &pcache, plist) {
if (p->equiv_cpu == new_patch->equiv_cpu) {
if (p->patch_id >= new_patch->patch_id)
/* we already have the latest patch */
return;
list_replace(&p->plist, &new_patch->plist);
kfree(p->data);
kfree(p);
return;
}
}
/* no patch found, add it */
list_add_tail(&new_patch->plist, &pcache);
}
static void free_cache(void)
{
struct ucode_patch *p, *tmp;
list_for_each_entry_safe(p, tmp, &pcache, plist) {
__list_del(p->plist.prev, p->plist.next);
kfree(p->data);
kfree(p);
}
}
static struct ucode_patch *find_patch(unsigned int cpu)
{
u16 equiv_id;
equiv_id = __find_equiv_id(cpu);
if (!equiv_id)
return NULL;
return cache_find_patch(equiv_id);
}
static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
struct ucode_patch *p;
csig->sig = cpuid_eax(0x00000001);
csig->rev = c->microcode;
/*
* a patch could have been loaded early, set uci->mc so that
* mc_bp_resume() can call apply_microcode()
*/
p = find_patch(cpu);
if (p && (p->patch_id == csig->rev))
uci->mc = p->data;
pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
return 0;
}
static unsigned int verify_patch_size(u8 family, u32 patch_size,
unsigned int size)
{
u32 max_size;
#define F1XH_MPB_MAX_SIZE 2048
#define F14H_MPB_MAX_SIZE 1824
#define F15H_MPB_MAX_SIZE 4096
#define F16H_MPB_MAX_SIZE 3458
switch (family) {
case 0x14:
max_size = F14H_MPB_MAX_SIZE;
break;
case 0x15:
max_size = F15H_MPB_MAX_SIZE;
break;
case 0x16:
max_size = F16H_MPB_MAX_SIZE;
break;
default:
max_size = F1XH_MPB_MAX_SIZE;
break;
}
if (patch_size > min_t(u32, size, max_size)) {
pr_err("patch size mismatch\n");
return 0;
}
return patch_size;
}
/*
* Those patch levels cannot be updated to newer ones and thus should be final.
*/
static u32 final_levels[] = {
0x01000098,
0x0100009f,
0x010000af,
0, /* T-101 terminator */
};
/*
* Check the current patch level on this CPU.
*
* @rev: Use it to return the patch level. It is set to 0 in the case of
* error.
*
* Returns:
* - true: if update should stop
* - false: otherwise
*/
bool check_current_patch_level(u32 *rev, bool early)
{
u32 lvl, dummy, i;
bool ret = false;
u32 *levels;
native_rdmsr(MSR_AMD64_PATCH_LEVEL, lvl, dummy);
if (IS_ENABLED(CONFIG_X86_32) && early)
levels = (u32 *)__pa_nodebug(&final_levels);
else
levels = final_levels;
for (i = 0; levels[i]; i++) {
if (lvl == levels[i]) {
lvl = 0;
ret = true;
break;
}
}
if (rev)
*rev = lvl;
return ret;
}
int __apply_microcode_amd(struct microcode_amd *mc_amd)
{
u32 rev, dummy;
native_wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
/* verify patch application was successful */
native_rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
if (rev != mc_amd->hdr.patch_id)
return -1;
return 0;
}
int apply_microcode_amd(int cpu)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);
struct microcode_amd *mc_amd;
struct ucode_cpu_info *uci;
struct ucode_patch *p;
u32 rev;
BUG_ON(raw_smp_processor_id() != cpu);
uci = ucode_cpu_info + cpu;
p = find_patch(cpu);
if (!p)
return 0;
mc_amd = p->data;
uci->mc = p->data;
if (check_current_patch_level(&rev, false))
return -1;
/* need to apply patch? */
if (rev >= mc_amd->hdr.patch_id) {
c->microcode = rev;
uci->cpu_sig.rev = rev;
return 0;
}
if (__apply_microcode_amd(mc_amd)) {
pr_err("CPU%d: update failed for patch_level=0x%08x\n",
cpu, mc_amd->hdr.patch_id);
return -1;
}
pr_info("CPU%d: new patch_level=0x%08x\n", cpu,
mc_amd->hdr.patch_id);
uci->cpu_sig.rev = mc_amd->hdr.patch_id;
c->microcode = mc_amd->hdr.patch_id;
return 0;
}
static int install_equiv_cpu_table(const u8 *buf)
{
unsigned int *ibuf = (unsigned int *)buf;
unsigned int type = ibuf[1];
unsigned int size = ibuf[2];
if (type != UCODE_EQUIV_CPU_TABLE_TYPE || !size) {
pr_err("empty section/"
"invalid type field in container file section header\n");
return -EINVAL;
}
equiv_cpu_table = vmalloc(size);
if (!equiv_cpu_table) {
pr_err("failed to allocate equivalent CPU table\n");
return -ENOMEM;
}
memcpy(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
/* add header length */
return size + CONTAINER_HDR_SZ;
}
static void free_equiv_cpu_table(void)
{
vfree(equiv_cpu_table);
equiv_cpu_table = NULL;
}
static void cleanup(void)
{
free_equiv_cpu_table();
free_cache();
}
/*
* We return the current size even if some of the checks failed so that
* we can skip over the next patch. If we return a negative value, we
* signal a grave error like a memory allocation has failed and the
* driver cannot continue functioning normally. In such cases, we tear
* down everything we've used up so far and exit.
*/
static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover)
{
struct microcode_header_amd *mc_hdr;
struct ucode_patch *patch;
unsigned int patch_size, crnt_size, ret;
u32 proc_fam;
u16 proc_id;
patch_size = *(u32 *)(fw + 4);
crnt_size = patch_size + SECTION_HDR_SIZE;
mc_hdr = (struct microcode_header_amd *)(fw + SECTION_HDR_SIZE);
proc_id = mc_hdr->processor_rev_id;
proc_fam = find_cpu_family_by_equiv_cpu(proc_id);
if (!proc_fam) {
pr_err("No patch family for equiv ID: 0x%04x\n", proc_id);
return crnt_size;
}
/* check if patch is for the current family */
proc_fam = ((proc_fam >> 8) & 0xf) + ((proc_fam >> 20) & 0xff);
if (proc_fam != family)
return crnt_size;
if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
pr_err("Patch-ID 0x%08x: chipset-specific code unsupported.\n",
mc_hdr->patch_id);
return crnt_size;
}
ret = verify_patch_size(family, patch_size, leftover);
if (!ret) {
pr_err("Patch-ID 0x%08x: size mismatch.\n", mc_hdr->patch_id);
return crnt_size;
}
patch = kzalloc(sizeof(*patch), GFP_KERNEL);
if (!patch) {
pr_err("Patch allocation failure.\n");
return -EINVAL;
}
patch->data = kzalloc(patch_size, GFP_KERNEL);
if (!patch->data) {
pr_err("Patch data allocation failure.\n");
kfree(patch);
return -EINVAL;
}
/* All looks ok, copy patch... */
memcpy(patch->data, fw + SECTION_HDR_SIZE, patch_size);
INIT_LIST_HEAD(&patch->plist);
patch->patch_id = mc_hdr->patch_id;
patch->equiv_cpu = proc_id;
pr_debug("%s: Added patch_id: 0x%08x, proc_id: 0x%04x\n",
__func__, patch->patch_id, proc_id);
/* ... and add to cache. */
update_cache(patch);
return crnt_size;
}
static enum ucode_state __load_microcode_amd(u8 family, const u8 *data,
size_t size)
{
enum ucode_state ret = UCODE_ERROR;
unsigned int leftover;
u8 *fw = (u8 *)data;
int crnt_size = 0;
int offset;
offset = install_equiv_cpu_table(data);
if (offset < 0) {
pr_err("failed to create equivalent cpu table\n");
return ret;
}
fw += offset;
leftover = size - offset;
if (*(u32 *)fw != UCODE_UCODE_TYPE) {
pr_err("invalid type field in container file section header\n");
free_equiv_cpu_table();
return ret;
}
while (leftover) {
crnt_size = verify_and_add_patch(family, fw, leftover);
if (crnt_size < 0)
return ret;
fw += crnt_size;
leftover -= crnt_size;
}
return UCODE_OK;
}
enum ucode_state load_microcode_amd(int cpu, u8 family, const u8 *data, size_t size)
{
enum ucode_state ret;
/* free old equiv table */
free_equiv_cpu_table();
ret = __load_microcode_amd(family, data, size);
if (ret != UCODE_OK)
cleanup();
#if defined(CONFIG_MICROCODE_AMD_EARLY) && defined(CONFIG_X86_32)
/* save BSP's matching patch for early load */
if (cpu_data(cpu).cpu_index == boot_cpu_data.cpu_index) {
struct ucode_patch *p = find_patch(cpu);
if (p) {
memset(amd_ucode_patch, 0, PATCH_MAX_SIZE);
memcpy(amd_ucode_patch, p->data, min_t(u32, ksize(p->data),
PATCH_MAX_SIZE));
}
}
#endif
return ret;
}
/*
* AMD microcode firmware naming convention, up to family 15h they are in
* the legacy file:
*
* amd-ucode/microcode_amd.bin
*
* This legacy file is always smaller than 2K in size.
*
* Beginning with family 15h, they are in family-specific firmware files:
*
* amd-ucode/microcode_amd_fam15h.bin
* amd-ucode/microcode_amd_fam16h.bin
* ...
*
* These might be larger than 2K.
*/
static enum ucode_state request_microcode_amd(int cpu, struct device *device,
bool refresh_fw)
{
char fw_name[36] = "amd-ucode/microcode_amd.bin";
struct cpuinfo_x86 *c = &cpu_data(cpu);
enum ucode_state ret = UCODE_NFOUND;
const struct firmware *fw;
/* reload ucode container only on the boot cpu */
if (!refresh_fw || c->cpu_index != boot_cpu_data.cpu_index)
return UCODE_OK;
if (c->x86 >= 0x15)
snprintf(fw_name, sizeof(fw_name), "amd-ucode/microcode_amd_fam%.2xh.bin", c->x86);
if (request_firmware_direct(&fw, (const char *)fw_name, device)) {
pr_debug("failed to load file %s\n", fw_name);
goto out;
}
ret = UCODE_ERROR;
if (*(u32 *)fw->data != UCODE_MAGIC) {
pr_err("invalid magic value (0x%08x)\n", *(u32 *)fw->data);
goto fw_release;
}
ret = load_microcode_amd(cpu, c->x86, fw->data, fw->size);
fw_release:
release_firmware(fw);
out:
return ret;
}
static enum ucode_state
request_microcode_user(int cpu, const void __user *buf, size_t size)
{
return UCODE_ERROR;
}
static void microcode_fini_cpu_amd(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
uci->mc = NULL;
}
static struct microcode_ops microcode_amd_ops = {
.request_microcode_user = request_microcode_user,
.request_microcode_fw = request_microcode_amd,
.collect_cpu_info = collect_cpu_info_amd,
.apply_microcode = apply_microcode_amd,
.microcode_fini_cpu = microcode_fini_cpu_amd,
};
struct microcode_ops * __init init_amd_microcode(void)
{
struct cpuinfo_x86 *c = &cpu_data(0);
if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10) {
pr_warning("AMD CPU family 0x%x not supported\n", c->x86);
return NULL;
}
return &microcode_amd_ops;
}
void __exit exit_amd_microcode(void)
{
cleanup();
}