x86: microcode: use smp_call_function_single instead of set_cpus_allowed, cleanup of synchronization logic

* Solve issues described in 6f66cbc630
  in a way that doesn't resort to set_cpus_allowed();

* in fact, only collect_cpu_info and apply_microcode callbacks
  must run on a target cpu, others will do just fine on any other.
  smp_call_function_single() (as suggested by Ingo) is used to run
  these callbacks on a target cpu.

* cleanup of synchronization logic of the 'microcode_core' part

  The generic 'microcode_core' part guarantees that only a single cpu
  (be it a full-fledged cpu, one of the cores or HT)
  is being updated at any particular moment of time.

  In general, there is no need for any additional sync. mechanism in
  arch-specific parts (the patch removes existing spinlocks).

  See also the "Synchronization" section in microcode_core.c.

* return -EINVAL instead of -1 (which is translated into -EPERM) in
  microcode_write(), reload_cpu() and mc_sysdev_add(). Other suggestions
  for an error code?

* use 'enum ucode_state' as return value of request_microcode_{fw, user}
  to gain more flexibility by distinguishing between real error cases
  and situations when an appropriate ucode was not found (which is not an
  error per-se).

* some minor cleanups

Thanks a lot to Hugh Dickins for review/suggestions/testing!

   Reference: http://marc.info/?l=linux-kernel&m=124025889012541&w=2

[ Impact: refactor and clean up microcode driver locking code ]

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Oruba <peter.oruba@amd.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <1242078507.5560.9.camel@earth>
[ did some more cleanups ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
 arch/x86/include/asm/microcode.h  |   25 ++
 arch/x86/kernel/microcode_amd.c   |   58 ++----
 arch/x86/kernel/microcode_core.c  |  326 +++++++++++++++++++++-----------------
 arch/x86/kernel/microcode_intel.c |   92 +++-------
 4 files changed, 261 insertions(+), 240 deletions(-)

(~20 new comment lines)
This commit is contained in:
Dmitry Adamushko 2009-05-11 23:48:27 +02:00 committed by Ingo Molnar
parent a4d7749be5
commit 871b72dd1e
4 changed files with 265 additions and 243 deletions

View File

@ -9,20 +9,31 @@ struct cpu_signature {
struct device;
enum ucode_state { UCODE_ERROR, UCODE_OK, UCODE_NFOUND };
struct microcode_ops {
int (*request_microcode_user) (int cpu, const void __user *buf, size_t size);
int (*request_microcode_fw) (int cpu, struct device *device);
enum ucode_state (*request_microcode_user) (int cpu,
const void __user *buf, size_t size);
void (*apply_microcode) (int cpu);
enum ucode_state (*request_microcode_fw) (int cpu,
struct device *device);
int (*collect_cpu_info) (int cpu, struct cpu_signature *csig);
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.
*/
int (*apply_microcode) (int cpu);
int (*collect_cpu_info) (int cpu, struct cpu_signature *csig);
};
struct ucode_cpu_info {
struct cpu_signature cpu_sig;
int valid;
void *mc;
struct cpu_signature cpu_sig;
int valid;
void *mc;
};
extern struct ucode_cpu_info ucode_cpu_info[];

View File

@ -13,25 +13,13 @@
* Licensed under the terms of the GNU General Public
* License version 2. See file COPYING for details.
*/
#include <linux/platform_device.h>
#include <linux/capability.h>
#include <linux/miscdevice.h>
#include <linux/firmware.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/pci_ids.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/pci.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <asm/microcode.h>
#include <asm/processor.h>
@ -79,9 +67,6 @@ struct microcode_amd {
#define UCODE_CONTAINER_SECTION_HDR 8
#define UCODE_CONTAINER_HEADER_SIZE 12
/* serialize access to the physical write */
static DEFINE_SPINLOCK(microcode_update_lock);
static struct equiv_cpu_entry *equiv_cpu_table;
static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
@ -144,9 +129,8 @@ static int get_matching_microcode(int cpu, void *mc, int rev)
return 1;
}
static void apply_microcode_amd(int cpu)
static int apply_microcode_amd(int cpu)
{
unsigned long flags;
u32 rev, dummy;
int cpu_num = raw_smp_processor_id();
struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
@ -156,25 +140,25 @@ static void apply_microcode_amd(int cpu)
BUG_ON(cpu_num != cpu);
if (mc_amd == NULL)
return;
return 0;
spin_lock_irqsave(&microcode_update_lock, flags);
wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
/* get patch id after patching */
rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
spin_unlock_irqrestore(&microcode_update_lock, flags);
/* check current patch id and patch's id for match */
if (rev != mc_amd->hdr.patch_id) {
printk(KERN_ERR "microcode: CPU%d: update failed "
"(for patch_level=0x%x)\n", cpu, mc_amd->hdr.patch_id);
return;
return -1;
}
printk(KERN_INFO "microcode: CPU%d: updated (new patch_level=0x%x)\n",
cpu, rev);
uci->cpu_sig.rev = rev;
return 0;
}
static int get_ucode_data(void *to, const u8 *from, size_t n)
@ -263,7 +247,8 @@ static void free_equiv_cpu_table(void)
}
}
static int generic_load_microcode(int cpu, const u8 *data, size_t size)
static enum ucode_state
generic_load_microcode(int cpu, const u8 *data, size_t size)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
const u8 *ucode_ptr = data;
@ -272,12 +257,13 @@ static int generic_load_microcode(int cpu, const u8 *data, size_t size)
int new_rev = uci->cpu_sig.rev;
unsigned int leftover;
unsigned long offset;
enum ucode_state state = UCODE_OK;
offset = install_equiv_cpu_table(ucode_ptr);
if (!offset) {
printk(KERN_ERR "microcode: failed to create "
"equivalent cpu table\n");
return -EINVAL;
return UCODE_ERROR;
}
ucode_ptr += offset;
@ -312,28 +298,27 @@ static int generic_load_microcode(int cpu, const u8 *data, size_t size)
pr_debug("microcode: CPU%d found a matching microcode "
"update with version 0x%x (current=0x%x)\n",
cpu, new_rev, uci->cpu_sig.rev);
} else
} else {
vfree(new_mc);
}
state = UCODE_ERROR;
}
} else
state = UCODE_NFOUND;
free_equiv_cpu_table();
return (int)leftover;
return state;
}
static int request_microcode_fw(int cpu, struct device *device)
static enum ucode_state request_microcode_fw(int cpu, struct device *device)
{
const char *fw_name = "amd-ucode/microcode_amd.bin";
const struct firmware *firmware;
int ret;
enum ucode_state ret;
/* We should bind the task to the CPU */
BUG_ON(cpu != raw_smp_processor_id());
ret = request_firmware(&firmware, fw_name, device);
if (ret) {
if (request_firmware(&firmware, fw_name, device)) {
printk(KERN_ERR "microcode: failed to load file %s\n", fw_name);
return ret;
return UCODE_NFOUND;
}
ret = generic_load_microcode(cpu, firmware->data, firmware->size);
@ -343,11 +328,12 @@ static int request_microcode_fw(int cpu, struct device *device)
return ret;
}
static int request_microcode_user(int cpu, const void __user *buf, size_t size)
static enum ucode_state
request_microcode_user(int cpu, const void __user *buf, size_t size)
{
printk(KERN_INFO "microcode: AMD microcode update via "
"/dev/cpu/microcode not supported\n");
return -1;
return UCODE_ERROR;
}
static void microcode_fini_cpu_amd(int cpu)

View File

@ -71,27 +71,18 @@
* Thanks to Stuart Swales for pointing out this bug.
*/
#include <linux/platform_device.h>
#include <linux/capability.h>
#include <linux/miscdevice.h>
#include <linux/firmware.h>
#include <linux/capability.h>
#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <asm/microcode.h>
#include <asm/processor.h>
#include <asm/msr.h>
MODULE_DESCRIPTION("Microcode Update Driver");
MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
@ -101,36 +92,110 @@ MODULE_LICENSE("GPL");
static struct microcode_ops *microcode_ops;
/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
/*
* Synchronization.
*
* All non cpu-hotplug-callback call sites use:
*
* - microcode_mutex to synchronize with each other;
* - get/put_online_cpus() 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];
EXPORT_SYMBOL_GPL(ucode_cpu_info);
/*
* Operations that are run on a target cpu:
*/
struct cpu_info_ctx {
struct cpu_signature *cpu_sig;
int err;
};
static void collect_cpu_info_local(void *arg)
{
struct cpu_info_ctx *ctx = arg;
ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(),
ctx->cpu_sig);
}
static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig)
{
struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 };
int ret;
ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1);
if (!ret)
ret = ctx.err;
return ret;
}
static int collect_cpu_info(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
int ret;
memset(uci, 0, sizeof(*uci));
ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig);
if (!ret)
uci->valid = 1;
return ret;
}
struct apply_microcode_ctx {
int err;
};
static void apply_microcode_local(void *arg)
{
struct apply_microcode_ctx *ctx = arg;
ctx->err = microcode_ops->apply_microcode(smp_processor_id());
}
static int apply_microcode_on_target(int cpu)
{
struct apply_microcode_ctx ctx = { .err = 0 };
int ret;
ret = smp_call_function_single(cpu, apply_microcode_local, &ctx, 1);
if (!ret)
ret = ctx.err;
return ret;
}
#ifdef CONFIG_MICROCODE_OLD_INTERFACE
static int do_microcode_update(const void __user *buf, size_t size)
{
cpumask_t old;
int error = 0;
int cpu;
old = current->cpus_allowed;
for_each_online_cpu(cpu) {
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
enum ucode_state ustate;
if (!uci->valid)
continue;
set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
error = microcode_ops->request_microcode_user(cpu, buf, size);
if (error < 0)
goto out;
if (!error)
microcode_ops->apply_microcode(cpu);
ustate = microcode_ops->request_microcode_user(cpu, buf, size);
if (ustate == UCODE_ERROR) {
error = -1;
break;
} else if (ustate == UCODE_OK)
apply_microcode_on_target(cpu);
}
out:
set_cpus_allowed_ptr(current, &old);
return error;
}
@ -143,19 +208,17 @@ static int microcode_open(struct inode *unused1, struct file *unused2)
static ssize_t microcode_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos)
{
ssize_t ret;
ssize_t ret = -EINVAL;
if ((len >> PAGE_SHIFT) > num_physpages) {
printk(KERN_ERR "microcode: too much data (max %ld pages)\n",
num_physpages);
return -EINVAL;
pr_err("microcode: too much data (max %ld pages)\n", num_physpages);
return ret;
}
get_online_cpus();
mutex_lock(&microcode_mutex);
ret = do_microcode_update(buf, len);
if (!ret)
if (do_microcode_update(buf, len) == 0)
ret = (ssize_t)len;
mutex_unlock(&microcode_mutex);
@ -165,15 +228,15 @@ static ssize_t microcode_write(struct file *file, const char __user *buf,
}
static const struct file_operations microcode_fops = {
.owner = THIS_MODULE,
.write = microcode_write,
.open = microcode_open,
.owner = THIS_MODULE,
.write = microcode_write,
.open = microcode_open,
};
static struct miscdevice microcode_dev = {
.minor = MICROCODE_MINOR,
.name = "microcode",
.fops = &microcode_fops,
.minor = MICROCODE_MINOR,
.name = "microcode",
.fops = &microcode_fops,
};
static int __init microcode_dev_init(void)
@ -182,9 +245,7 @@ static int __init microcode_dev_init(void)
error = misc_register(&microcode_dev);
if (error) {
printk(KERN_ERR
"microcode: can't misc_register on minor=%d\n",
MICROCODE_MINOR);
pr_err("microcode: can't misc_register on minor=%d\n", MICROCODE_MINOR);
return error;
}
@ -205,42 +266,51 @@ MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
/* fake device for request_firmware */
static struct platform_device *microcode_pdev;
static long reload_for_cpu(void *unused)
static int reload_for_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + smp_processor_id();
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
int err = 0;
mutex_lock(&microcode_mutex);
if (uci->valid) {
err = microcode_ops->request_microcode_fw(smp_processor_id(),
&microcode_pdev->dev);
if (!err)
microcode_ops->apply_microcode(smp_processor_id());
enum ucode_state ustate;
ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
if (ustate == UCODE_OK)
apply_microcode_on_target(cpu);
else
if (ustate == UCODE_ERROR)
err = -EINVAL;
}
mutex_unlock(&microcode_mutex);
return err;
}
static ssize_t reload_store(struct sys_device *dev,
struct sysdev_attribute *attr,
const char *buf, size_t sz)
const char *buf, size_t size)
{
char *end;
unsigned long val = simple_strtoul(buf, &end, 0);
int err = 0;
unsigned long val;
int cpu = dev->id;
int ret = 0;
char *end;
val = simple_strtoul(buf, &end, 0);
if (end == buf)
return -EINVAL;
if (val == 1) {
get_online_cpus();
if (cpu_online(cpu))
err = work_on_cpu(cpu, reload_for_cpu, NULL);
ret = reload_for_cpu(cpu);
put_online_cpus();
}
if (err)
return err;
return sz;
if (!ret)
ret = size;
return ret;
}
static ssize_t version_show(struct sys_device *dev,
@ -271,11 +341,11 @@ static struct attribute *mc_default_attrs[] = {
};
static struct attribute_group mc_attr_group = {
.attrs = mc_default_attrs,
.name = "microcode",
.attrs = mc_default_attrs,
.name = "microcode",
};
static void __microcode_fini_cpu(int cpu)
static void microcode_fini_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
@ -283,103 +353,68 @@ static void __microcode_fini_cpu(int cpu)
uci->valid = 0;
}
static void microcode_fini_cpu(int cpu)
{
mutex_lock(&microcode_mutex);
__microcode_fini_cpu(cpu);
mutex_unlock(&microcode_mutex);
}
static void collect_cpu_info(int cpu)
static enum ucode_state microcode_resume_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
memset(uci, 0, sizeof(*uci));
if (!microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig))
uci->valid = 1;
}
static int microcode_resume_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
struct cpu_signature nsig;
pr_debug("microcode: CPU%d resumed\n", cpu);
if (!uci->mc)
return 1;
return UCODE_NFOUND;
/*
* Let's verify that the 'cached' ucode does belong
* to this cpu (a bit of paranoia):
*/
if (microcode_ops->collect_cpu_info(cpu, &nsig)) {
__microcode_fini_cpu(cpu);
printk(KERN_ERR "failed to collect_cpu_info for resuming cpu #%d\n",
cpu);
return -1;
}
pr_debug("microcode: CPU%d updated upon resume\n", cpu);
apply_microcode_on_target(cpu);
if ((nsig.sig != uci->cpu_sig.sig) || (nsig.pf != uci->cpu_sig.pf)) {
__microcode_fini_cpu(cpu);
printk(KERN_ERR "cached ucode doesn't match the resuming cpu #%d\n",
cpu);
/* Should we look for a new ucode here? */
return 1;
}
return 0;
return UCODE_OK;
}
static long microcode_update_cpu(void *unused)
static enum ucode_state microcode_init_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + smp_processor_id();
int err = 0;
enum ucode_state ustate;
/*
* Check if the system resume is in progress (uci->valid != NULL),
* otherwise just request a firmware:
*/
if (uci->valid) {
err = microcode_resume_cpu(smp_processor_id());
} else {
collect_cpu_info(smp_processor_id());
if (uci->valid && system_state == SYSTEM_RUNNING)
err = microcode_ops->request_microcode_fw(
smp_processor_id(),
&microcode_pdev->dev);
if (collect_cpu_info(cpu))
return UCODE_ERROR;
/* --dimm. Trigger a delayed update? */
if (system_state != SYSTEM_RUNNING)
return UCODE_NFOUND;
ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
if (ustate == UCODE_OK) {
pr_debug("microcode: CPU%d updated upon init\n", cpu);
apply_microcode_on_target(cpu);
}
if (!err)
microcode_ops->apply_microcode(smp_processor_id());
return err;
return ustate;
}
static int microcode_init_cpu(int cpu)
static enum ucode_state microcode_update_cpu(int cpu)
{
int err;
mutex_lock(&microcode_mutex);
err = work_on_cpu(cpu, microcode_update_cpu, NULL);
mutex_unlock(&microcode_mutex);
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
enum ucode_state ustate;
return err;
if (uci->valid)
ustate = microcode_resume_cpu(cpu);
else
ustate = microcode_init_cpu(cpu);
return ustate;
}
static int mc_sysdev_add(struct sys_device *sys_dev)
{
int err, cpu = sys_dev->id;
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
if (!cpu_online(cpu))
return 0;
pr_debug("microcode: CPU%d added\n", cpu);
memset(uci, 0, sizeof(*uci));
err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group);
if (err)
return err;
err = microcode_init_cpu(cpu);
if (microcode_init_cpu(cpu) == UCODE_ERROR)
err = -EINVAL;
return err;
}
@ -400,19 +435,30 @@ static int mc_sysdev_remove(struct sys_device *sys_dev)
static int mc_sysdev_resume(struct sys_device *dev)
{
int cpu = dev->id;
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
if (!cpu_online(cpu))
return 0;
/* only CPU 0 will apply ucode here */
microcode_update_cpu(NULL);
/*
* All non-bootup cpus are still disabled,
* so only CPU 0 will apply ucode here.
*
* Moreover, there can be no concurrent
* updates from any other places at this point.
*/
WARN_ON(cpu != 0);
if (uci->valid && uci->mc)
microcode_ops->apply_microcode(cpu);
return 0;
}
static struct sysdev_driver mc_sysdev_driver = {
.add = mc_sysdev_add,
.remove = mc_sysdev_remove,
.resume = mc_sysdev_resume,
.add = mc_sysdev_add,
.remove = mc_sysdev_remove,
.resume = mc_sysdev_resume,
};
static __cpuinit int
@ -425,15 +471,12 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
switch (action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
if (microcode_init_cpu(cpu))
printk(KERN_ERR "microcode: failed to init CPU%d\n",
cpu);
microcode_update_cpu(cpu);
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
pr_debug("microcode: CPU%d added\n", cpu);
if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group))
printk(KERN_ERR "microcode: Failed to create the sysfs "
"group for CPU%d\n", cpu);
pr_err("microcode: Failed to create group for CPU%d\n", cpu);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
@ -465,13 +508,10 @@ static int __init microcode_init(void)
microcode_ops = init_amd_microcode();
if (!microcode_ops) {
printk(KERN_ERR "microcode: no support for this CPU vendor\n");
pr_err("microcode: no support for this CPU vendor\n");
return -ENODEV;
}
error = microcode_dev_init();
if (error)
return error;
microcode_pdev = platform_device_register_simple("microcode", -1,
NULL, 0);
if (IS_ERR(microcode_pdev)) {
@ -480,23 +520,31 @@ static int __init microcode_init(void)
}
get_online_cpus();
mutex_lock(&microcode_mutex);
error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver);
mutex_unlock(&microcode_mutex);
put_online_cpus();
if (error) {
microcode_dev_exit();
platform_device_unregister(microcode_pdev);
return error;
}
error = microcode_dev_init();
if (error)
return error;
register_hotcpu_notifier(&mc_cpu_notifier);
printk(KERN_INFO
"Microcode Update Driver: v" MICROCODE_VERSION
pr_info("Microcode Update Driver: v" MICROCODE_VERSION
" <tigran@aivazian.fsnet.co.uk>,"
" Peter Oruba\n");
return 0;
}
module_init(microcode_init);
static void __exit microcode_exit(void)
{
@ -505,16 +553,17 @@ static void __exit microcode_exit(void)
unregister_hotcpu_notifier(&mc_cpu_notifier);
get_online_cpus();
mutex_lock(&microcode_mutex);
sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver);
mutex_unlock(&microcode_mutex);
put_online_cpus();
platform_device_unregister(microcode_pdev);
microcode_ops = NULL;
printk(KERN_INFO
"Microcode Update Driver: v" MICROCODE_VERSION " removed.\n");
pr_info("Microcode Update Driver: v" MICROCODE_VERSION " removed.\n");
}
module_init(microcode_init);
module_exit(microcode_exit);

View File

@ -70,24 +70,11 @@
* Fix sigmatch() macro to handle old CPUs with pf == 0.
* Thanks to Stuart Swales for pointing out this bug.
*/
#include <linux/platform_device.h>
#include <linux/capability.h>
#include <linux/miscdevice.h>
#include <linux/firmware.h>
#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <asm/microcode.h>
#include <asm/processor.h>
@ -150,13 +137,9 @@ struct extended_sigtable {
#define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
/* serialize access to the physical write to MSR 0x79 */
static DEFINE_SPINLOCK(microcode_update_lock);
static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
{
struct cpuinfo_x86 *c = &cpu_data(cpu_num);
unsigned long flags;
unsigned int val[2];
memset(csig, 0, sizeof(*csig));
@ -176,18 +159,14 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
csig->pf = 1 << ((val[1] >> 18) & 7);
}
/* serialize access to the physical write to MSR 0x79 */
spin_lock_irqsave(&microcode_update_lock, flags);
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
/* see notes above for revision 1.07. Apparent chip bug */
sync_core();
/* get the current revision from MSR 0x8B */
rdmsr(MSR_IA32_UCODE_REV, val[0], csig->rev);
spin_unlock_irqrestore(&microcode_update_lock, flags);
pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
csig->sig, csig->pf, csig->rev);
printk(KERN_INFO "microcode: CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n",
cpu_num, csig->sig, csig->pf, csig->rev);
return 0;
}
@ -318,11 +297,10 @@ get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
return 0;
}
static void apply_microcode(int cpu)
static int apply_microcode(int cpu)
{
struct microcode_intel *mc_intel;
struct ucode_cpu_info *uci;
unsigned long flags;
unsigned int val[2];
int cpu_num;
@ -334,10 +312,7 @@ static void apply_microcode(int cpu)
BUG_ON(cpu_num != cpu);
if (mc_intel == NULL)
return;
/* serialize access to the physical write to MSR 0x79 */
spin_lock_irqsave(&microcode_update_lock, flags);
return 0;
/* write microcode via MSR 0x79 */
wrmsr(MSR_IA32_UCODE_WRITE,
@ -351,30 +326,32 @@ static void apply_microcode(int cpu)
/* get the current revision from MSR 0x8B */
rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
spin_unlock_irqrestore(&microcode_update_lock, flags);
if (val[1] != mc_intel->hdr.rev) {
printk(KERN_ERR "microcode: CPU%d update from revision "
"0x%x to 0x%x failed\n",
cpu_num, uci->cpu_sig.rev, val[1]);
return;
printk(KERN_ERR "microcode: CPU%d update "
"to revision 0x%x failed\n",
cpu_num, mc_intel->hdr.rev);
return -1;
}
printk(KERN_INFO "microcode: CPU%d updated from revision "
"0x%x to 0x%x, date = %04x-%02x-%02x \n",
cpu_num, uci->cpu_sig.rev, val[1],
printk(KERN_INFO "microcode: CPU%d updated to revision "
"0x%x, date = %04x-%02x-%02x \n",
cpu_num, val[1],
mc_intel->hdr.date & 0xffff,
mc_intel->hdr.date >> 24,
(mc_intel->hdr.date >> 16) & 0xff);
uci->cpu_sig.rev = val[1];
return 0;
}
static int generic_load_microcode(int cpu, void *data, size_t size,
int (*get_ucode_data)(void *, const void *, size_t))
static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
int (*get_ucode_data)(void *, const void *, size_t))
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
u8 *ucode_ptr = data, *new_mc = NULL, *mc;
int new_rev = uci->cpu_sig.rev;
unsigned int leftover = size;
enum ucode_state state = UCODE_OK;
while (leftover) {
struct microcode_header_intel mc_header;
@ -412,11 +389,15 @@ static int generic_load_microcode(int cpu, void *data, size_t size,
leftover -= mc_size;
}
if (!new_mc)
goto out;
if (leftover) {
vfree(new_mc);
if (new_mc)
vfree(new_mc);
state = UCODE_ERROR;
goto out;
}
if (!new_mc) {
state = UCODE_NFOUND;
goto out;
}
@ -427,9 +408,8 @@ static int generic_load_microcode(int cpu, void *data, size_t size,
pr_debug("microcode: CPU%d found a matching microcode update with"
" version 0x%x (current=0x%x)\n",
cpu, new_rev, uci->cpu_sig.rev);
out:
return (int)leftover;
out:
return state;
}
static int get_ucode_fw(void *to, const void *from, size_t n)
@ -438,21 +418,19 @@ static int get_ucode_fw(void *to, const void *from, size_t n)
return 0;
}
static int request_microcode_fw(int cpu, struct device *device)
static enum ucode_state request_microcode_fw(int cpu, struct device *device)
{
char name[30];
struct cpuinfo_x86 *c = &cpu_data(cpu);
const struct firmware *firmware;
int ret;
enum ucode_state ret;
/* We should bind the task to the CPU */
BUG_ON(cpu != raw_smp_processor_id());
sprintf(name, "intel-ucode/%02x-%02x-%02x",
c->x86, c->x86_model, c->x86_mask);
ret = request_firmware(&firmware, name, device);
if (ret) {
if (request_firmware(&firmware, name, device)) {
pr_debug("microcode: data file %s load failed\n", name);
return ret;
return UCODE_NFOUND;
}
ret = generic_load_microcode(cpu, (void *)firmware->data,
@ -468,11 +446,9 @@ static int get_ucode_user(void *to, const void *from, size_t n)
return copy_from_user(to, from, n);
}
static int request_microcode_user(int cpu, const void __user *buf, size_t size)
static enum ucode_state
request_microcode_user(int cpu, const void __user *buf, size_t size)
{
/* We should bind the task to the CPU */
BUG_ON(cpu != raw_smp_processor_id());
return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
}