[tip:x86/microcode] x86: microcode: use smp_call_function_single instead of set_cpus_allowed, cleanup of synchronization logic

From: tip-bot for Dmitry Adamushko
Date: Tue May 12 2009 - 04:43:37 EST

Commit-ID: 871b72dd1e12afc3f024479531d25a9339d2e3f9
Gitweb: http://git.kernel.org/tip/871b72dd1e12afc3f024479531d25a9339d2e3f9
Author: Dmitry Adamushko <dmitry.adamushko@xxxxxxxxx>
AuthorDate: Mon, 11 May 2009 23:48:27 +0200
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Tue, 12 May 2009 10:36:44 +0200

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

* Solve issues described in 6f66cbc63081fd70e3191b4dbb796746780e5ae1
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@xxxxxxxxx>
Acked-by: Hugh Dickins <hugh@xxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Andreas Herrmann <andreas.herrmann3@xxxxxxx>
Cc: Peter Oruba <peter.oruba@xxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxx>
LKML-Reference: <1242078507.5560.9.camel@earth>
[ did some more cleanups ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
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)


---
arch/x86/include/asm/microcode.h | 25 ++-
arch/x86/kernel/microcode_amd.c | 58 +++----
arch/x86/kernel/microcode_core.c | 329 +++++++++++++++++++++----------------
arch/x86/kernel/microcode_intel.c | 90 ++++-------
4 files changed, 262 insertions(+), 240 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index c882664..ef51b50 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -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[];

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 453b579..c8be20f 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -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;
-
- /* We should bind the task to the CPU */
- BUG_ON(cpu != raw_smp_processor_id());
+ enum ucode_state ret;

- 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)
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 98c470c..9c44615 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -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@xxxxxxxxxxxxxxxxxxxx>");
@@ -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;
+ if (!uci->mc)
+ return UCODE_NFOUND;
+
+ pr_debug("microcode: CPU%d updated upon resume\n", cpu);
+ apply_microcode_on_target(cpu);
+
+ return UCODE_OK;
}

-static int microcode_resume_cpu(int cpu)
+static enum ucode_state microcode_init_cpu(int cpu)
{
- struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
- struct cpu_signature nsig;
+ enum ucode_state ustate;

- pr_debug("microcode: CPU%d resumed\n", cpu);
+ if (collect_cpu_info(cpu))
+ return UCODE_ERROR;

- if (!uci->mc)
- return 1;
+ /* --dimm. Trigger a delayed update? */
+ if (system_state != SYSTEM_RUNNING)
+ 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;
- }
+ ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);

- 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;
+ if (ustate == UCODE_OK) {
+ pr_debug("microcode: CPU%d updated upon init\n", cpu);
+ apply_microcode_on_target(cpu);
}

- return 0;
+ return ustate;
}

-static long microcode_update_cpu(void *unused)
+static enum ucode_state microcode_update_cpu(int cpu)
{
- struct ucode_cpu_info *uci = ucode_cpu_info + smp_processor_id();
- int err = 0;
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+ 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 (!err)
- microcode_ops->apply_microcode(smp_processor_id());
- return err;
-}
+ if (uci->valid)
+ ustate = microcode_resume_cpu(cpu);
+ else
+ ustate = microcode_init_cpu(cpu);

-static int microcode_init_cpu(int cpu)
-{
- int err;
- mutex_lock(&microcode_mutex);
- err = work_on_cpu(cpu, microcode_update_cpu, NULL);
- mutex_unlock(&microcode_mutex);
-
- return err;
+ 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@xxxxxxxxxxxxxxxxxxxx>,"
" 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);
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 149b9ec..0d334dd 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -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)
+ if (leftover) {
+ if (new_mc)
+ vfree(new_mc);
+ state = UCODE_ERROR;
goto out;
+ }

- if (leftover) {
- vfree(new_mc);
+ 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);
}

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