[PATCH v0 0/12] x86, microcode, AMD: Per-family patches cache

[PATCH v0 0/12] x86, microcode, AMD: Per-family patches cache

[Borislav Petkov]

Hi all,

here's a set of patches which adds code for caching all microcode
patches which belong to the current family on which we're running. We
look up the patch needed for each core from the cache at application
time instead of holding a single patch per-system.

Also, each commit message should contain additional, hopefully sensible
information about each change.

Patchset has been tested on all families which are supported by the
microcode loader ( >= 0x10).

As always, all comments and suggestions are appreciated.

Thanks.

[PATCH v0 02/12] x86, microcode: Save an indentation level in reload_for_cpu

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Invert the uci->valid check so that the later block can be aligned on
the first indentation level of the function. No functional change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_core.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 4873e62db6a1..63a956865022 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -276,19 +276,18 @@ static struct platform_device	*microcode_pdev;
 static int reload_for_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	enum ucode_state ustate;
 	int err = 0;
 
-	if (uci->valid) {
-		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;
-	}
+	if (!uci->valid)
+		return err;
 
+	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;
 	return err;
 }
 
-- 
1.7.11.rc1

[PATCH v0 03/12] x86, microcode: Drop uci->mc check on resume path

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Remove the uci->mc check on the cpu resume path because the low-level
drivers do that anyway.

More importantly, though, this fixes a contrived and obscure but still
important case. Imagine the following:

* boot machine, no new microcode in /lib/firmware

* a subset of the CPUs is offlined

* in the meantime, user puts new fresh microcode container into
/lib/firmware and reloads it by doing
$ echo 1 > /sys/devices/system/cpu/microcode/reload

* offlined cores come back online and they don't get the newer microcode
applied due to this check.

Later patches take care of the issue on AMD.

While at it, cleanup code around it.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_core.c | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 63a956865022..706a5c9b8eb2 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -369,13 +369,10 @@ static void microcode_fini_cpu(int cpu)
 
 static enum ucode_state microcode_resume_cpu(int cpu)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-
-	if (!uci->mc)
-		return UCODE_NFOUND;
-
 	pr_debug("CPU%d updated upon resume\n", cpu);
-	apply_microcode_on_target(cpu);
+
+	if (apply_microcode_on_target(cpu))
+		return UCODE_ERROR;
 
 	return UCODE_OK;
 }
@@ -404,14 +401,11 @@ static enum ucode_state microcode_init_cpu(int cpu)
 static enum ucode_state microcode_update_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	enum ucode_state ustate;
 
 	if (uci->valid)
-		ustate = microcode_resume_cpu(cpu);
-	else
-		ustate = microcode_init_cpu(cpu);
+		return microcode_resume_cpu(cpu);
 
-	return ustate;
+	return microcode_init_cpu(cpu);
 }
 
 static int mc_device_add(struct device *dev, struct subsys_interface *sif)
-- 
1.7.11.rc1

[PATCH v0 04/12] x86, microcode: Cleanup cpu hotplug notifier callback

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Mask out CPU_TASKS_FROZEN bit so that all _FROZEN cases can be dropped.
Also, add some more comments as to why CPU_ONLINE falls through to
CPU_DOWN_FAILED (no break), and for the CPU_DEAD case. Realign debug
printks better.

Idea blatantly stolen from a tglx patch:
http://marc.info/?l=linux-kernel&m=134267779513862

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_core.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 706a5c9b8eb2..dcde544e012c 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -470,34 +470,41 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
 	struct device *dev;
 
 	dev = get_cpu_device(cpu);
-	switch (action) {
+
+	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
 		microcode_update_cpu(cpu);
-	case CPU_DOWN_FAILED:
-	case CPU_DOWN_FAILED_FROZEN:
 		pr_debug("CPU%d added\n", cpu);
+		/*
+		 * "break" is missing on purpose here because we want to fall
+		 * through in order to create the sysfs group.
+		 */
+
+	case CPU_DOWN_FAILED:
 		if (sysfs_create_group(&dev->kobj, &mc_attr_group))
 			pr_err("Failed to create group for CPU%d\n", cpu);
 		break;
+
 	case CPU_DOWN_PREPARE:
-	case CPU_DOWN_PREPARE_FROZEN:
 		/* Suspend is in progress, only remove the interface */
 		sysfs_remove_group(&dev->kobj, &mc_attr_group);
 		pr_debug("CPU%d removed\n", cpu);
 		break;
 
 	/*
+	 * case CPU_DEAD:
+	 *
 	 * When a CPU goes offline, don't free up or invalidate the copy of
 	 * the microcode in kernel memory, so that we can reuse it when the
 	 * CPU comes back online without unnecessarily requesting the userspace
 	 * for it again.
 	 */
-	case CPU_UP_CANCELED_FROZEN:
-		/* The CPU refused to come up during a system resume */
-		microcode_fini_cpu(cpu);
-		break;
 	}
+
+	/* The CPU refused to come up during a system resume */
+	if (action == CPU_UP_CANCELED_FROZEN)
+		microcode_fini_cpu(cpu);
+
 	return NOTIFY_OK;
 }
 
-- 
1.7.11.rc1

[PATCH v0 05/12] x86, microcode: Straighten out Kconfig text

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Update and clarify Kconfig help text along with menu names.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/Kconfig | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ec3a1aa4abd..1ccccc6efb37 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -982,25 +982,25 @@ config X86_REBOOTFIXUPS
 	  Say N otherwise.
 
 config MICROCODE
-	tristate "/dev/cpu/microcode - microcode support"
+	tristate "CPU microcode loading support"
 	select FW_LOADER
 	---help---
+
 	  If you say Y here, you will be able to update the microcode on
 	  certain Intel and AMD processors. The Intel support is for the
-	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
-	  Pentium 4, Xeon etc. The AMD support is for family 0x10 and
-	  0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
-	  You will obviously need the actual microcode binary data itself
-	  which is not shipped with the Linux kernel.
+	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
+	  Xeon etc. The AMD support is for families 0x10 and later. You will
+	  obviously need the actual microcode binary data itself which is not
+	  shipped with the Linux kernel.
 
 	  This option selects the general module only, you need to select
 	  at least one vendor specific module as well.
 
-	  To compile this driver as a module, choose M here: the
-	  module will be called microcode.
+	  To compile this driver as a module, choose M here: the module
+	  will be called microcode.
 
 config MICROCODE_INTEL
-	bool "Intel microcode patch loading support"
+	bool "Intel microcode loading support"
 	depends on MICROCODE
 	default MICROCODE
 	select FW_LOADER
@@ -1013,7 +1013,7 @@ config MICROCODE_INTEL
 	  <http://www.urbanmyth.org/microcode/>.
 
 config MICROCODE_AMD
-	bool "AMD microcode patch loading support"
+	bool "AMD microcode loading support"
 	depends on MICROCODE
 	select FW_LOADER
 	---help---
-- 
1.7.11.rc1

[PATCH v0 06/12] x86, microcode, AMD: Remove useless get_ucode_data wrapper

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

get_ucode_data was a trivial memcpy wrapper. Remove it so as not to
obfuscate code unnecessarily with no obvious gain.

No functional change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/include/asm/microcode.h | 6 ------
 arch/x86/kernel/microcode_amd.c  | 4 ++--
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 4ebe157bf73d..8813be600995 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -49,12 +49,6 @@ static inline struct microcode_ops * __init init_intel_microcode(void)
 #ifdef CONFIG_MICROCODE_AMD
 extern struct microcode_ops * __init init_amd_microcode(void);
 extern void __exit exit_amd_microcode(void);
-
-static inline void get_ucode_data(void *to, const u8 *from, size_t n)
-{
-	memcpy(to, from, n);
-}
-
 #else
 static inline struct microcode_ops * __init init_amd_microcode(void)
 {
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 82746f942cd8..94213387a3d1 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -183,7 +183,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 	memset(patch, 0, PAGE_SIZE);
 
 	/* all looks ok, get the binary patch */
-	get_ucode_data(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
+	memcpy(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
 
 	return actual_size;
 }
@@ -238,7 +238,7 @@ static int install_equiv_cpu_table(const u8 *buf)
 		return -ENOMEM;
 	}
 
-	get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
+	memcpy(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
 
 	/* add header length */
 	return size + CONTAINER_HDR_SZ;
-- 
1.7.11.rc1

[PATCH v0 07/12] x86, microcode, AMD: Check before applying a patch

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Make sure we're actually applying a microcode patch to a core which
really needs it.

This brings only a very very very minor slowdown on F10:

0.032218828 sec vs 0.056010626 sec with this patch.

And small speedup on F15:

0.487089449 sec vs 0.180551162 sec (from perf output).

Also, fixup comments while at it.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_amd.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 94213387a3d1..8fdf7d99b804 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -202,11 +202,18 @@ static int apply_microcode_amd(int cpu)
 	if (mc_amd == NULL)
 		return 0;
 
-	wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
-	/* get patch id after patching */
 	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
-	/* check current patch id and patch's id for match */
+	/* need to apply patch? */
+	if (rev >= mc_amd->hdr.patch_id) {
+		c->microcode = rev;
+		return 0;
+	}
+
+	wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
+
+	/* verify patch application was successful */
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 	if (rev != mc_amd->hdr.patch_id) {
 		pr_err("CPU%d: update failed for patch_level=0x%08x\n",
 		       cpu, mc_amd->hdr.patch_id);
-- 
1.7.11.rc1

[PATCH v0 08/12] x86, microcode, AMD: Read CPUID(1).EAX on the correct cpu

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Read the CPUID(1).EAX leaf at the correct cpu and use it to search the
equivalence table for matching microcode patch. No functionality change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_amd.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 8fdf7d99b804..25d34b177482 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -82,6 +82,7 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
 
+	csig->sig = cpuid_eax(0x00000001);
 	csig->rev = c->microcode;
 	pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
 
@@ -118,16 +119,15 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-static u16 find_equiv_id(void)
+static u16 find_equiv_id(unsigned int cpu)
 {
-	unsigned int current_cpu_id, i = 0;
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	int i = 0;
 
 	BUG_ON(equiv_cpu_table == NULL);
 
-	current_cpu_id = cpuid_eax(0x00000001);
-
 	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (current_cpu_id == equiv_cpu_table[i].installed_cpu)
+		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
 			return equiv_cpu_table[i].equiv_cpu;
 
 		i++;
@@ -150,7 +150,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 	patch_size = *(u32 *)(ucode_ptr + 4);
 	*current_size = patch_size + SECTION_HDR_SIZE;
 
-	equiv_cpu_id = find_equiv_id();
+	equiv_cpu_id = find_equiv_id(cpu);
 	if (!equiv_cpu_id)
 		return 0;
 
-- 
1.7.11.rc1

[PATCH v0 09/12] x86, microcode: Add a refresh firmware flag to ->request_microcode_fw

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

This is done in preparation for teaching the ucode driver to either load
a new ucode patches container from userspace or use an already cached
version. No functionality change in this patch.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/include/asm/microcode.h  |  4 ++--
 arch/x86/kernel/microcode_amd.c   |  3 ++-
 arch/x86/kernel/microcode_core.c  | 11 ++++++-----
 arch/x86/kernel/microcode_intel.c |  3 ++-
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 8813be600995..43d921b4752c 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -15,8 +15,8 @@ struct microcode_ops {
 	enum ucode_state (*request_microcode_user) (int cpu,
 				const void __user *buf, size_t size);
 
-	enum ucode_state (*request_microcode_fw) (int cpu,
-				struct device *device);
+	enum ucode_state (*request_microcode_fw) (int cpu, struct device *,
+						  bool refresh_fw);
 
 	void (*microcode_fini_cpu) (int cpu);
 
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 25d34b177482..94ecdaa24052 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -330,7 +330,8 @@ out:
  *
  * These might be larger than 2K.
  */
-static enum ucode_state request_microcode_amd(int cpu, struct device *device)
+static enum ucode_state request_microcode_amd(int cpu, struct device *device,
+					      bool refresh_fw)
 {
 	char fw_name[36] = "amd-ucode/microcode_amd.bin";
 	const struct firmware *fw;
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index dcde544e012c..9420972e98fe 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -282,7 +282,7 @@ static int reload_for_cpu(int cpu)
 	if (!uci->valid)
 		return err;
 
-	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev, true);
 	if (ustate == UCODE_OK)
 		apply_microcode_on_target(cpu);
 	else
@@ -377,7 +377,7 @@ static enum ucode_state microcode_resume_cpu(int cpu)
 	return UCODE_OK;
 }
 
-static enum ucode_state microcode_init_cpu(int cpu)
+static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
 {
 	enum ucode_state ustate;
 
@@ -388,7 +388,8 @@ static enum ucode_state microcode_init_cpu(int cpu)
 	if (system_state != SYSTEM_RUNNING)
 		return UCODE_NFOUND;
 
-	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev,
+						     refresh_fw);
 
 	if (ustate == UCODE_OK) {
 		pr_debug("CPU%d updated upon init\n", cpu);
@@ -405,7 +406,7 @@ static enum ucode_state microcode_update_cpu(int cpu)
 	if (uci->valid)
 		return microcode_resume_cpu(cpu);
 
-	return microcode_init_cpu(cpu);
+	return microcode_init_cpu(cpu, false);
 }
 
 static int mc_device_add(struct device *dev, struct subsys_interface *sif)
@@ -421,7 +422,7 @@ static int mc_device_add(struct device *dev, struct subsys_interface *sif)
 	if (err)
 		return err;
 
-	if (microcode_init_cpu(cpu) == UCODE_ERROR)
+	if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
 		return -EINVAL;
 
 	return err;
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 0327e2b3c408..3544aed39338 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -405,7 +405,8 @@ static int get_ucode_fw(void *to, const void *from, size_t n)
 	return 0;
 }
 
-static enum ucode_state request_microcode_fw(int cpu, struct device *device)
+static enum ucode_state request_microcode_fw(int cpu, struct device *device,
+					     bool refresh_fw)
 {
 	char name[30];
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
-- 
1.7.11.rc1

[PATCH v0 10/12] x86, microcode, AMD: Add reverse equiv table search

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

We search the equivalence table using the CPUID(1) signature of the
CPU in order to get the equivalence ID of the patch which we need to
apply. Add a function which does the reverse - it will be needed in
later patches.

While at it, pull the other equiv table function up in the file so that
it can be used by other functionality without forward declarations.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_amd.c | 46 +++++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 94ecdaa24052..03ed5af7053d 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -78,6 +78,36 @@ static struct equiv_cpu_entry *equiv_cpu_table;
 /* page-sized ucode patch buffer */
 void *patch;
 
+static u16 find_equiv_id(unsigned int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	int i = 0;
+
+	BUG_ON(equiv_cpu_table == NULL);
+
+	while (equiv_cpu_table[i].installed_cpu != 0) {
+		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
+			return equiv_cpu_table[i].equiv_cpu;
+
+		i++;
+	}
+	return 0;
+}
+
+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;
+}
+
 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -119,22 +149,6 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-static u16 find_equiv_id(unsigned int cpu)
-{
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	int i = 0;
-
-	BUG_ON(equiv_cpu_table == NULL);
-
-	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
-			return equiv_cpu_table[i].equiv_cpu;
-
-		i++;
-	}
-	return 0;
-}
-
 /*
  * we signal a good patch is found by returning its size > 0
  */
-- 
1.7.11.rc1

[PATCH v0 11/12] x86, microcode, AMD: Add a small, per-family patches cache

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

This is a trivial cache which collects all ucode patches for the current
family of CPUs on the system. If a newer patch appears due to the
container file being updated in userspace, we replace our cached version
with the new one.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_amd.c | 67 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 66 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 03ed5af7053d..cacdc9a5ee49 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -78,12 +78,22 @@ static struct equiv_cpu_entry *equiv_cpu_table;
 /* page-sized ucode patch buffer */
 void *patch;
 
+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;
 	int i = 0;
 
-	BUG_ON(equiv_cpu_table == NULL);
+	if (!equiv_cpu_table)
+		return 0;
 
 	while (equiv_cpu_table[i].installed_cpu != 0) {
 		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
@@ -108,6 +118,61 @@ static u32 find_cpu_family_by_equiv_cpu(u16 equiv_cpu)
 	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;
+
+	list_for_each_entry_reverse(p, &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);
-- 
1.7.11.rc1

[PATCH v0 12/12] x86, microcode, AMD: Rewrite patch application procedure

[Borislav Petkov]

From: Borislav Petkov <borislav.petkov@amd.com>

Limit the access to userspace only on the BSP where we load the
container, verify the patches in it and put them in the patch cache.
Then, at application time, we lookup the correct patch in the cache and
use it.

When we need to reload the userspace container, we do that over the
reload interface:

echo 1 > /sys/devices/system/cpu/microcode/reload

which reloads (a possibly newer) container from userspace and applies
then the newest patches from there.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/kernel/microcode_amd.c | 236 ++++++++++++++++++++--------------------
 1 file changed, 121 insertions(+), 115 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index cacdc9a5ee49..5511216b4434 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -75,9 +75,6 @@ struct microcode_amd {
 
 static struct equiv_cpu_entry *equiv_cpu_table;
 
-/* page-sized ucode patch buffer */
-void *patch;
-
 struct ucode_patch {
 	struct list_head plist;
 	void *data;
@@ -184,7 +181,7 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 	return 0;
 }
 
-static unsigned int verify_ucode_size(int cpu, u32 patch_size,
+static unsigned int verify_patch_size(int cpu, u32 patch_size,
 				      unsigned int size)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -214,73 +211,25 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-/*
- * we signal a good patch is found by returning its size > 0
- */
-static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
-				  unsigned int leftover_size, int rev,
-				  unsigned int *current_size)
-{
-	struct microcode_header_amd *mc_hdr;
-	unsigned int actual_size, patch_size;
-	u16 equiv_cpu_id;
-
-	/* size of the current patch we're staring at */
-	patch_size = *(u32 *)(ucode_ptr + 4);
-	*current_size = patch_size + SECTION_HDR_SIZE;
-
-	equiv_cpu_id = find_equiv_id(cpu);
-	if (!equiv_cpu_id)
-		return 0;
-
-	/*
-	 * let's look at the patch header itself now
-	 */
-	mc_hdr = (struct microcode_header_amd *)(ucode_ptr + SECTION_HDR_SIZE);
-
-	if (mc_hdr->processor_rev_id != equiv_cpu_id)
-		return 0;
-
-	/* ucode might be chipset specific -- currently we don't support this */
-	if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
-		pr_err("CPU%d: chipset specific code not yet supported\n",
-		       cpu);
-		return 0;
-	}
-
-	if (mc_hdr->patch_id <= rev)
-		return 0;
-
-	/*
-	 * now that the header looks sane, verify its size
-	 */
-	actual_size = verify_ucode_size(cpu, patch_size, leftover_size);
-	if (!actual_size)
-		return 0;
-
-	/* clear the patch buffer */
-	memset(patch, 0, PAGE_SIZE);
-
-	/* all looks ok, get the binary patch */
-	memcpy(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
-
-	return actual_size;
-}
-
 static int apply_microcode_amd(int cpu)
 {
-	u32 rev, dummy;
-	int cpu_num = raw_smp_processor_id();
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
-	struct microcode_amd *mc_amd = uci->mc;
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct microcode_amd *mc_amd;
+	struct ucode_cpu_info *uci;
+	struct ucode_patch *p;
+	u32 rev, dummy;
+
+	BUG_ON(raw_smp_processor_id() != cpu);
 
-	/* We should bind the task to the CPU */
-	BUG_ON(cpu_num != cpu);
+	uci = ucode_cpu_info + cpu;
 
-	if (mc_amd == NULL)
+	p = find_patch(cpu);
+	if (!p)
 		return 0;
 
+	mc_amd  = p->data;
+	uci->mc = p->data;
+
 	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
 	/* need to apply patch? */
@@ -336,61 +285,113 @@ static void free_equiv_cpu_table(void)
 	equiv_cpu_table = NULL;
 }
 
-static enum ucode_state
-generic_load_microcode(int cpu, const u8 *data, size_t size)
+static void cleanup(void)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	struct microcode_header_amd *mc_hdr = NULL;
-	unsigned int mc_size, leftover, current_size = 0;
+	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(unsigned int cpu, u8 *fw, unsigned int leftover)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	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 != c->x86)
+		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(cpu, 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;
+
+	/* ... and add to cache. */
+	update_cache(patch);
+
+	return crnt_size;
+}
+
+static enum ucode_state load_microcode_amd(int cpu, 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;
-	const u8 *ucode_ptr = data;
-	void *new_mc = NULL;
-	unsigned int new_rev = uci->cpu_sig.rev;
-	enum ucode_state state = UCODE_ERROR;
 
-	offset = install_equiv_cpu_table(ucode_ptr);
+	offset = install_equiv_cpu_table(data);
 	if (offset < 0) {
 		pr_err("failed to create equivalent cpu table\n");
-		goto out;
+		return ret;
 	}
-	ucode_ptr += offset;
+	fw += offset;
 	leftover = size - offset;
 
-	if (*(u32 *)ucode_ptr != UCODE_UCODE_TYPE) {
+	if (*(u32 *)fw != UCODE_UCODE_TYPE) {
 		pr_err("invalid type field in container file section header\n");
-		goto free_table;
+		free_equiv_cpu_table();
+		return ret;
 	}
 
 	while (leftover) {
-		mc_size = get_matching_microcode(cpu, ucode_ptr, leftover,
-						 new_rev, &current_size);
-		if (mc_size) {
-			mc_hdr  = patch;
-			new_mc  = patch;
-			new_rev = mc_hdr->patch_id;
-			goto out_ok;
-		}
+		crnt_size = verify_and_add_patch(cpu, fw, leftover);
+		if (crnt_size < 0)
+			return ret;
 
-		ucode_ptr += current_size;
-		leftover  -= current_size;
+		fw	 += crnt_size;
+		leftover -= crnt_size;
 	}
 
-	if (!new_mc) {
-		state = UCODE_NFOUND;
-		goto free_table;
-	}
-
-out_ok:
-	uci->mc = new_mc;
-	state = UCODE_OK;
-	pr_debug("CPU%d update ucode (0x%08x -> 0x%08x)\n",
-		 cpu, uci->cpu_sig.rev, new_rev);
-
-free_table:
-	free_equiv_cpu_table();
-
-out:
-	return state;
+	return UCODE_OK;
 }
 
 /*
@@ -401,7 +402,7 @@ out:
  *
  * This legacy file is always smaller than 2K in size.
  *
- * Starting at family 15h they are in family specific firmware files:
+ * Beginning with family 15h, they are in family-specific firmware files:
  *
  *    amd-ucode/microcode_amd_fam15h.bin
  *    amd-ucode/microcode_amd_fam16h.bin
@@ -413,9 +414,13 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
 					      bool refresh_fw)
 {
 	char fw_name[36] = "amd-ucode/microcode_amd.bin";
-	const struct firmware *fw;
-	enum ucode_state ret = UCODE_NFOUND;
 	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);
@@ -431,12 +436,17 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
 		goto fw_release;
 	}
 
-	ret = generic_load_microcode(cpu, fw->data, fw->size);
+	/* free old equiv table */
+	free_equiv_cpu_table();
+
+	ret = load_microcode_amd(cpu, fw->data, fw->size);
+	if (ret != UCODE_OK)
+		cleanup();
 
-fw_release:
+ fw_release:
 	release_firmware(fw);
 
-out:
+ out:
 	return ret;
 }
 
@@ -470,14 +480,10 @@ struct microcode_ops * __init init_amd_microcode(void)
 		return NULL;
 	}
 
-	patch = (void *)get_zeroed_page(GFP_KERNEL);
-	if (!patch)
-		return NULL;
-
 	return &microcode_amd_ops;
 }
 
 void __exit exit_amd_microcode(void)
 {
-	free_page((unsigned long)patch);
+	cleanup();
 }
-- 
1.7.11.rc1

[tip:x86/urgent] x86, microcode, AMD: Fix broken ucode patch size check

[tip-bot for Andreas Herrmann]

Commit-ID:  36bf50d7697be18c6bfd0401e037df10bff1e573
Gitweb:     http://git.kernel.org/tip/36bf50d7697be18c6bfd0401e037df10bff1e573
Author:     Andreas Herrmann <andreas.herrmann3@amd.com>
AuthorDate: Tue, 31 Jul 2012 15:41:45 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:10:41 -0700

x86, microcode, AMD: Fix broken ucode patch size check

This issue was recently observed on an AMD C-50 CPU where a patch of
maximum size was applied.

Commit be62adb49294 ("x86, microcode, AMD: Simplify ucode verification")
added current_size in get_matching_microcode(). This is calculated as
size of the ucode patch + 8 (ie. size of the header). Later this is
compared against the maximum possible ucode patch size for a CPU family.
And of course this fails if the patch has already maximum size.

Cc: <stable@vger.kernel.org> [3.3+]
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-1-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 8a2ce8f..82746f9 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -143,11 +143,12 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 				  unsigned int *current_size)
 {
 	struct microcode_header_amd *mc_hdr;
-	unsigned int actual_size;
+	unsigned int actual_size, patch_size;
 	u16 equiv_cpu_id;
 
 	/* size of the current patch we're staring at */
-	*current_size = *(u32 *)(ucode_ptr + 4) + SECTION_HDR_SIZE;
+	patch_size = *(u32 *)(ucode_ptr + 4);
+	*current_size = patch_size + SECTION_HDR_SIZE;
 
 	equiv_cpu_id = find_equiv_id();
 	if (!equiv_cpu_id)
@@ -174,7 +175,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 	/*
 	 * now that the header looks sane, verify its size
 	 */
-	actual_size = verify_ucode_size(cpu, *current_size, leftover_size);
+	actual_size = verify_ucode_size(cpu, patch_size, leftover_size);
 	if (!actual_size)
 		return 0;
 

[tip:x86/microcode] x86, microcode: Save an indentation level in reload_for_cpu

[tip-bot for Borislav Petkov]

Commit-ID:  4dbf32c30f7e5379588a692c7bf80b05d9ef8026
Gitweb:     http://git.kernel.org/tip/4dbf32c30f7e5379588a692c7bf80b05d9ef8026
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Mon, 23 Jul 2012 19:05:53 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:14:08 -0700

x86, microcode: Save an indentation level in reload_for_cpu

Invert the uci->valid check so that the later block can be aligned on
the first indentation level of the function. No functional change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-3-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_core.c |   19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 4873e62..63a9568 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -276,19 +276,18 @@ static struct platform_device	*microcode_pdev;
 static int reload_for_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	enum ucode_state ustate;
 	int err = 0;
 
-	if (uci->valid) {
-		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;
-	}
+	if (!uci->valid)
+		return err;
 
+	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;
 	return err;
 }
 

[tip:x86/microcode] x86, microcode: Drop uci-> mc check on resume path

[tip-bot for Borislav Petkov]

Commit-ID:  bb9d3e473d5b324907e15dff4e54410b28ea50e2
Gitweb:     http://git.kernel.org/tip/bb9d3e473d5b324907e15dff4e54410b28ea50e2
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Fri, 3 Aug 2012 15:26:50 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:14:44 -0700

x86, microcode: Drop uci->mc check on resume path

Remove the uci->mc check on the cpu resume path because the low-level
drivers do that anyway.

More importantly, though, this fixes a contrived and obscure but still
important case. Imagine the following:

* boot machine, no new microcode in /lib/firmware

* a subset of the CPUs is offlined

* in the meantime, user puts new fresh microcode container into
/lib/firmware and reloads it by doing
$ echo 1 > /sys/devices/system/cpu/microcode/reload

* offlined cores come back online and they don't get the newer microcode
applied due to this check.

Later patches take care of the issue on AMD.

While at it, cleanup code around it.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-4-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_core.c |   16 +++++-----------
 1 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 63a9568..706a5c9 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -369,13 +369,10 @@ static void microcode_fini_cpu(int cpu)
 
 static enum ucode_state microcode_resume_cpu(int cpu)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-
-	if (!uci->mc)
-		return UCODE_NFOUND;
-
 	pr_debug("CPU%d updated upon resume\n", cpu);
-	apply_microcode_on_target(cpu);
+
+	if (apply_microcode_on_target(cpu))
+		return UCODE_ERROR;
 
 	return UCODE_OK;
 }
@@ -404,14 +401,11 @@ static enum ucode_state microcode_init_cpu(int cpu)
 static enum ucode_state microcode_update_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	enum ucode_state ustate;
 
 	if (uci->valid)
-		ustate = microcode_resume_cpu(cpu);
-	else
-		ustate = microcode_init_cpu(cpu);
+		return microcode_resume_cpu(cpu);
 
-	return ustate;
+	return microcode_init_cpu(cpu);
 }
 
 static int mc_device_add(struct device *dev, struct subsys_interface *sif)

[tip:x86/microcode] x86, microcode: Cleanup cpu hotplug notifier callback

[tip-bot for Borislav Petkov]

Commit-ID:  09c3f0d883300c8fc2bb62e9a70cf89a2ada9a80
Gitweb:     http://git.kernel.org/tip/09c3f0d883300c8fc2bb62e9a70cf89a2ada9a80
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Mon, 23 Jul 2012 20:15:10 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:14:52 -0700

x86, microcode: Cleanup cpu hotplug notifier callback

Mask out CPU_TASKS_FROZEN bit so that all _FROZEN cases can be dropped.
Also, add some more comments as to why CPU_ONLINE falls through to
CPU_DOWN_FAILED (no break), and for the CPU_DEAD case. Realign debug
printks better.

Idea blatantly stolen from a tglx patch:
http://marc.info/?l=linux-kernel&m=134267779513862

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-5-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_core.c |   25 ++++++++++++++++---------
 1 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 706a5c9..dcde544 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -470,34 +470,41 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
 	struct device *dev;
 
 	dev = get_cpu_device(cpu);
-	switch (action) {
+
+	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
 		microcode_update_cpu(cpu);
-	case CPU_DOWN_FAILED:
-	case CPU_DOWN_FAILED_FROZEN:
 		pr_debug("CPU%d added\n", cpu);
+		/*
+		 * "break" is missing on purpose here because we want to fall
+		 * through in order to create the sysfs group.
+		 */
+
+	case CPU_DOWN_FAILED:
 		if (sysfs_create_group(&dev->kobj, &mc_attr_group))
 			pr_err("Failed to create group for CPU%d\n", cpu);
 		break;
+
 	case CPU_DOWN_PREPARE:
-	case CPU_DOWN_PREPARE_FROZEN:
 		/* Suspend is in progress, only remove the interface */
 		sysfs_remove_group(&dev->kobj, &mc_attr_group);
 		pr_debug("CPU%d removed\n", cpu);
 		break;
 
 	/*
+	 * case CPU_DEAD:
+	 *
 	 * When a CPU goes offline, don't free up or invalidate the copy of
 	 * the microcode in kernel memory, so that we can reuse it when the
 	 * CPU comes back online without unnecessarily requesting the userspace
 	 * for it again.
 	 */
-	case CPU_UP_CANCELED_FROZEN:
-		/* The CPU refused to come up during a system resume */
-		microcode_fini_cpu(cpu);
-		break;
 	}
+
+	/* The CPU refused to come up during a system resume */
+	if (action == CPU_UP_CANCELED_FROZEN)
+		microcode_fini_cpu(cpu);
+
 	return NOTIFY_OK;
 }
 

[tip:x86/microcode] x86, microcode: Straighten out Kconfig text

[tip-bot for Borislav Petkov]

Commit-ID:  e43f6e67ec1c142550860bbe0b51166c5ee4cac8
Gitweb:     http://git.kernel.org/tip/e43f6e67ec1c142550860bbe0b51166c5ee4cac8
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 1 Aug 2012 19:17:01 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:16 -0700

x86, microcode: Straighten out Kconfig text

Update and clarify Kconfig help text along with menu names.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-6-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/Kconfig |   20 ++++++++++----------
 1 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ec3a1a..1ccccc6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -982,25 +982,25 @@ config X86_REBOOTFIXUPS
 	  Say N otherwise.
 
 config MICROCODE
-	tristate "/dev/cpu/microcode - microcode support"
+	tristate "CPU microcode loading support"
 	select FW_LOADER
 	---help---
+
 	  If you say Y here, you will be able to update the microcode on
 	  certain Intel and AMD processors. The Intel support is for the
-	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
-	  Pentium 4, Xeon etc. The AMD support is for family 0x10 and
-	  0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
-	  You will obviously need the actual microcode binary data itself
-	  which is not shipped with the Linux kernel.
+	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
+	  Xeon etc. The AMD support is for families 0x10 and later. You will
+	  obviously need the actual microcode binary data itself which is not
+	  shipped with the Linux kernel.
 
 	  This option selects the general module only, you need to select
 	  at least one vendor specific module as well.
 
-	  To compile this driver as a module, choose M here: the
-	  module will be called microcode.
+	  To compile this driver as a module, choose M here: the module
+	  will be called microcode.
 
 config MICROCODE_INTEL
-	bool "Intel microcode patch loading support"
+	bool "Intel microcode loading support"
 	depends on MICROCODE
 	default MICROCODE
 	select FW_LOADER
@@ -1013,7 +1013,7 @@ config MICROCODE_INTEL
 	  <http://www.urbanmyth.org/microcode/>.
 
 config MICROCODE_AMD
-	bool "AMD microcode patch loading support"
+	bool "AMD microcode loading support"
 	depends on MICROCODE
 	select FW_LOADER
 	---help---

[tip:x86/microcode] x86, microcode, AMD: Remove useless get_ucode_data wrapper

[tip-bot for Borislav Petkov]

Commit-ID:  e7e632f5ba240fbc313c49ed6559681ea57534e9
Gitweb:     http://git.kernel.org/tip/e7e632f5ba240fbc313c49ed6559681ea57534e9
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Fri, 20 Jul 2012 14:12:21 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:26 -0700

x86, microcode, AMD: Remove useless get_ucode_data wrapper

get_ucode_data was a trivial memcpy wrapper. Remove it so as not to
obfuscate code unnecessarily with no obvious gain.

No functional change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-7-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/include/asm/microcode.h |    6 ------
 arch/x86/kernel/microcode_amd.c  |    4 ++--
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 4ebe157..8813be6 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -49,12 +49,6 @@ static inline struct microcode_ops * __init init_intel_microcode(void)
 #ifdef CONFIG_MICROCODE_AMD
 extern struct microcode_ops * __init init_amd_microcode(void);
 extern void __exit exit_amd_microcode(void);
-
-static inline void get_ucode_data(void *to, const u8 *from, size_t n)
-{
-	memcpy(to, from, n);
-}
-
 #else
 static inline struct microcode_ops * __init init_amd_microcode(void)
 {
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 82746f9..9421338 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -183,7 +183,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 	memset(patch, 0, PAGE_SIZE);
 
 	/* all looks ok, get the binary patch */
-	get_ucode_data(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
+	memcpy(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
 
 	return actual_size;
 }
@@ -238,7 +238,7 @@ static int install_equiv_cpu_table(const u8 *buf)
 		return -ENOMEM;
 	}
 
-	get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
+	memcpy(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
 
 	/* add header length */
 	return size + CONTAINER_HDR_SZ;

[tip:x86/microcode] x86, microcode, AMD: Check before applying a patch

[tip-bot for Borislav Petkov]

Commit-ID:  685ca6d797af9d41164dd64dd60145d4946fc152
Gitweb:     http://git.kernel.org/tip/685ca6d797af9d41164dd64dd60145d4946fc152
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 20 Jun 2012 16:17:51 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:41 -0700

x86, microcode, AMD: Check before applying a patch

Make sure we're actually applying a microcode patch to a core which
really needs it.

This brings only a very very very minor slowdown on F10:

0.032218828 sec vs 0.056010626 sec with this patch.

And small speedup on F15:

0.487089449 sec vs 0.180551162 sec (from perf output).

Also, fixup comments while at it.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-8-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 9421338..8fdf7d9 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -202,11 +202,18 @@ static int apply_microcode_amd(int cpu)
 	if (mc_amd == NULL)
 		return 0;
 
-	wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
-	/* get patch id after patching */
 	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
-	/* check current patch id and patch's id for match */
+	/* need to apply patch? */
+	if (rev >= mc_amd->hdr.patch_id) {
+		c->microcode = rev;
+		return 0;
+	}
+
+	wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
+
+	/* verify patch application was successful */
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 	if (rev != mc_amd->hdr.patch_id) {
 		pr_err("CPU%d: update failed for patch_level=0x%08x\n",
 		       cpu, mc_amd->hdr.patch_id);

[tip:x86/microcode] x86, microcode, AMD: Read CPUID(1). EAX on the correct cpu

[tip-bot for Borislav Petkov]

Commit-ID:  5f5b747282c6cc57b91baba37f76de27398b9e60
Gitweb:     http://git.kernel.org/tip/5f5b747282c6cc57b91baba37f76de27398b9e60
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 25 Jul 2012 20:06:54 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:50 -0700

x86, microcode, AMD: Read CPUID(1).EAX on the correct cpu

Read the CPUID(1).EAX leaf at the correct cpu and use it to search the
equivalence table for matching microcode patch. No functionality change.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-9-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 8fdf7d9..25d34b1 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -82,6 +82,7 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
 
+	csig->sig = cpuid_eax(0x00000001);
 	csig->rev = c->microcode;
 	pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
 
@@ -118,16 +119,15 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-static u16 find_equiv_id(void)
+static u16 find_equiv_id(unsigned int cpu)
 {
-	unsigned int current_cpu_id, i = 0;
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	int i = 0;
 
 	BUG_ON(equiv_cpu_table == NULL);
 
-	current_cpu_id = cpuid_eax(0x00000001);
-
 	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (current_cpu_id == equiv_cpu_table[i].installed_cpu)
+		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
 			return equiv_cpu_table[i].equiv_cpu;
 
 		i++;
@@ -150,7 +150,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
 	patch_size = *(u32 *)(ucode_ptr + 4);
 	*current_size = patch_size + SECTION_HDR_SIZE;
 
-	equiv_cpu_id = find_equiv_id();
+	equiv_cpu_id = find_equiv_id(cpu);
 	if (!equiv_cpu_id)
 		return 0;
 

[tip:x86/microcode] x86, microcode: Add a refresh firmware flag to ->request_microcode_fw

[tip-bot for Borislav Petkov]

Commit-ID:  48e30685caa8bdc4b8d4417d8ac31db59689742c
Gitweb:     http://git.kernel.org/tip/48e30685caa8bdc4b8d4417d8ac31db59689742c
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Thu, 26 Jul 2012 15:51:00 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:58 -0700

x86, microcode: Add a refresh firmware flag to ->request_microcode_fw

This is done in preparation for teaching the ucode driver to either load
a new ucode patches container from userspace or use an already cached
version. No functionality change in this patch.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-10-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/include/asm/microcode.h  |    4 ++--
 arch/x86/kernel/microcode_amd.c   |    3 ++-
 arch/x86/kernel/microcode_core.c  |   11 ++++++-----
 arch/x86/kernel/microcode_intel.c |    3 ++-
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 8813be6..43d921b 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -15,8 +15,8 @@ struct microcode_ops {
 	enum ucode_state (*request_microcode_user) (int cpu,
 				const void __user *buf, size_t size);
 
-	enum ucode_state (*request_microcode_fw) (int cpu,
-				struct device *device);
+	enum ucode_state (*request_microcode_fw) (int cpu, struct device *,
+						  bool refresh_fw);
 
 	void (*microcode_fini_cpu) (int cpu);
 
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 25d34b1..94ecdaa 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -330,7 +330,8 @@ out:
  *
  * These might be larger than 2K.
  */
-static enum ucode_state request_microcode_amd(int cpu, struct device *device)
+static enum ucode_state request_microcode_amd(int cpu, struct device *device,
+					      bool refresh_fw)
 {
 	char fw_name[36] = "amd-ucode/microcode_amd.bin";
 	const struct firmware *fw;
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index dcde544..9420972 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -282,7 +282,7 @@ static int reload_for_cpu(int cpu)
 	if (!uci->valid)
 		return err;
 
-	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev, true);
 	if (ustate == UCODE_OK)
 		apply_microcode_on_target(cpu);
 	else
@@ -377,7 +377,7 @@ static enum ucode_state microcode_resume_cpu(int cpu)
 	return UCODE_OK;
 }
 
-static enum ucode_state microcode_init_cpu(int cpu)
+static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
 {
 	enum ucode_state ustate;
 
@@ -388,7 +388,8 @@ static enum ucode_state microcode_init_cpu(int cpu)
 	if (system_state != SYSTEM_RUNNING)
 		return UCODE_NFOUND;
 
-	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev,
+						     refresh_fw);
 
 	if (ustate == UCODE_OK) {
 		pr_debug("CPU%d updated upon init\n", cpu);
@@ -405,7 +406,7 @@ static enum ucode_state microcode_update_cpu(int cpu)
 	if (uci->valid)
 		return microcode_resume_cpu(cpu);
 
-	return microcode_init_cpu(cpu);
+	return microcode_init_cpu(cpu, false);
 }
 
 static int mc_device_add(struct device *dev, struct subsys_interface *sif)
@@ -421,7 +422,7 @@ static int mc_device_add(struct device *dev, struct subsys_interface *sif)
 	if (err)
 		return err;
 
-	if (microcode_init_cpu(cpu) == UCODE_ERROR)
+	if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
 		return -EINVAL;
 
 	return err;
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 0327e2b..3544aed 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -405,7 +405,8 @@ static int get_ucode_fw(void *to, const void *from, size_t n)
 	return 0;
 }
 
-static enum ucode_state request_microcode_fw(int cpu, struct device *device)
+static enum ucode_state request_microcode_fw(int cpu, struct device *device,
+					     bool refresh_fw)
 {
 	char name[30];
 	struct cpuinfo_x86 *c = &cpu_data(cpu);

[tip:x86/microcode] x86, microcode, AMD: Add reverse equiv table search

[tip-bot for Borislav Petkov]

Commit-ID:  c96d2c0905cc48e34f2b37b775b59932c416b343
Gitweb:     http://git.kernel.org/tip/c96d2c0905cc48e34f2b37b775b59932c416b343
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 1 Aug 2012 14:55:01 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:16:11 -0700

x86, microcode, AMD: Add reverse equiv table search

We search the equivalence table using the CPUID(1) signature of the
CPU in order to get the equivalence ID of the patch which we need to
apply. Add a function which does the reverse - it will be needed in
later patches.

While at it, pull the other equiv table function up in the file so that
it can be used by other functionality without forward declarations.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-11-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |   46 +++++++++++++++++++++++++-------------
 1 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 94ecdaa..03ed5af 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -78,6 +78,36 @@ static struct equiv_cpu_entry *equiv_cpu_table;
 /* page-sized ucode patch buffer */
 void *patch;
 
+static u16 find_equiv_id(unsigned int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	int i = 0;
+
+	BUG_ON(equiv_cpu_table == NULL);
+
+	while (equiv_cpu_table[i].installed_cpu != 0) {
+		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
+			return equiv_cpu_table[i].equiv_cpu;
+
+		i++;
+	}
+	return 0;
+}
+
+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;
+}
+
 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -119,22 +149,6 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-static u16 find_equiv_id(unsigned int cpu)
-{
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	int i = 0;
-
-	BUG_ON(equiv_cpu_table == NULL);
-
-	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
-			return equiv_cpu_table[i].equiv_cpu;
-
-		i++;
-	}
-	return 0;
-}
-
 /*
  * we signal a good patch is found by returning its size > 0
  */

[tip:x86/microcode] x86, microcode, AMD: Add a small, per-family patches cache

[tip-bot for Borislav Petkov]

Commit-ID:  a3eb3b4da106a23b5d41bf915726172e31654a65
Gitweb:     http://git.kernel.org/tip/a3eb3b4da106a23b5d41bf915726172e31654a65
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 1 Aug 2012 15:38:18 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:16:21 -0700

x86, microcode, AMD: Add a small, per-family patches cache

This is a trivial cache which collects all ucode patches for the current
family of CPUs on the system. If a newer patch appears due to the
container file being updated in userspace, we replace our cached version
with the new one.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-12-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |   67 ++++++++++++++++++++++++++++++++++++++-
 1 files changed, 66 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 03ed5af..cacdc9a 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -78,12 +78,22 @@ static struct equiv_cpu_entry *equiv_cpu_table;
 /* page-sized ucode patch buffer */
 void *patch;
 
+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;
 	int i = 0;
 
-	BUG_ON(equiv_cpu_table == NULL);
+	if (!equiv_cpu_table)
+		return 0;
 
 	while (equiv_cpu_table[i].installed_cpu != 0) {
 		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
@@ -108,6 +118,61 @@ static u32 find_cpu_family_by_equiv_cpu(u16 equiv_cpu)
 	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;
+
+	list_for_each_entry_reverse(p, &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);

[tip:x86/microcode] x86, microcode, AMD: Rewrite patch application procedure

[tip-bot for Borislav Petkov]

Commit-ID:  2efb05e8e9fa3510044e007b90263c73b6a83f84
Gitweb:     http://git.kernel.org/tip/2efb05e8e9fa3510044e007b90263c73b6a83f84
Author:     Borislav Petkov <borislav.petkov@amd.com>
AuthorDate: Wed, 1 Aug 2012 16:16:13 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:16:29 -0700

x86, microcode, AMD: Rewrite patch application procedure

Limit the access to userspace only on the BSP where we load the
container, verify the patches in it and put them in the patch cache.
Then, at application time, we lookup the correct patch in the cache and
use it.

When we need to reload the userspace container, we do that over the
reload interface:

echo 1 > /sys/devices/system/cpu/microcode/reload

which reloads (a possibly newer) container from userspace and applies
then the newest patches from there.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-13-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |  236 ++++++++++++++++++++-------------------
 1 files changed, 121 insertions(+), 115 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index cacdc9a..5511216 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -75,9 +75,6 @@ struct microcode_amd {
 
 static struct equiv_cpu_entry *equiv_cpu_table;
 
-/* page-sized ucode patch buffer */
-void *patch;
-
 struct ucode_patch {
 	struct list_head plist;
 	void *data;
@@ -184,7 +181,7 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 	return 0;
 }
 
-static unsigned int verify_ucode_size(int cpu, u32 patch_size,
+static unsigned int verify_patch_size(int cpu, u32 patch_size,
 				      unsigned int size)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -214,73 +211,25 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-/*
- * we signal a good patch is found by returning its size > 0
- */
-static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
-				  unsigned int leftover_size, int rev,
-				  unsigned int *current_size)
-{
-	struct microcode_header_amd *mc_hdr;
-	unsigned int actual_size, patch_size;
-	u16 equiv_cpu_id;
-
-	/* size of the current patch we're staring at */
-	patch_size = *(u32 *)(ucode_ptr + 4);
-	*current_size = patch_size + SECTION_HDR_SIZE;
-
-	equiv_cpu_id = find_equiv_id(cpu);
-	if (!equiv_cpu_id)
-		return 0;
-
-	/*
-	 * let's look at the patch header itself now
-	 */
-	mc_hdr = (struct microcode_header_amd *)(ucode_ptr + SECTION_HDR_SIZE);
-
-	if (mc_hdr->processor_rev_id != equiv_cpu_id)
-		return 0;
-
-	/* ucode might be chipset specific -- currently we don't support this */
-	if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
-		pr_err("CPU%d: chipset specific code not yet supported\n",
-		       cpu);
-		return 0;
-	}
-
-	if (mc_hdr->patch_id <= rev)
-		return 0;
-
-	/*
-	 * now that the header looks sane, verify its size
-	 */
-	actual_size = verify_ucode_size(cpu, patch_size, leftover_size);
-	if (!actual_size)
-		return 0;
-
-	/* clear the patch buffer */
-	memset(patch, 0, PAGE_SIZE);
-
-	/* all looks ok, get the binary patch */
-	memcpy(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
-
-	return actual_size;
-}
-
 static int apply_microcode_amd(int cpu)
 {
-	u32 rev, dummy;
-	int cpu_num = raw_smp_processor_id();
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
-	struct microcode_amd *mc_amd = uci->mc;
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct microcode_amd *mc_amd;
+	struct ucode_cpu_info *uci;
+	struct ucode_patch *p;
+	u32 rev, dummy;
+
+	BUG_ON(raw_smp_processor_id() != cpu);
 
-	/* We should bind the task to the CPU */
-	BUG_ON(cpu_num != cpu);
+	uci = ucode_cpu_info + cpu;
 
-	if (mc_amd == NULL)
+	p = find_patch(cpu);
+	if (!p)
 		return 0;
 
+	mc_amd  = p->data;
+	uci->mc = p->data;
+
 	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
 	/* need to apply patch? */
@@ -336,61 +285,113 @@ static void free_equiv_cpu_table(void)
 	equiv_cpu_table = NULL;
 }
 
-static enum ucode_state
-generic_load_microcode(int cpu, const u8 *data, size_t size)
+static void cleanup(void)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	struct microcode_header_amd *mc_hdr = NULL;
-	unsigned int mc_size, leftover, current_size = 0;
+	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(unsigned int cpu, u8 *fw, unsigned int leftover)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	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 != c->x86)
+		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(cpu, 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;
+
+	/* ... and add to cache. */
+	update_cache(patch);
+
+	return crnt_size;
+}
+
+static enum ucode_state load_microcode_amd(int cpu, 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;
-	const u8 *ucode_ptr = data;
-	void *new_mc = NULL;
-	unsigned int new_rev = uci->cpu_sig.rev;
-	enum ucode_state state = UCODE_ERROR;
 
-	offset = install_equiv_cpu_table(ucode_ptr);
+	offset = install_equiv_cpu_table(data);
 	if (offset < 0) {
 		pr_err("failed to create equivalent cpu table\n");
-		goto out;
+		return ret;
 	}
-	ucode_ptr += offset;
+	fw += offset;
 	leftover = size - offset;
 
-	if (*(u32 *)ucode_ptr != UCODE_UCODE_TYPE) {
+	if (*(u32 *)fw != UCODE_UCODE_TYPE) {
 		pr_err("invalid type field in container file section header\n");
-		goto free_table;
+		free_equiv_cpu_table();
+		return ret;
 	}
 
 	while (leftover) {
-		mc_size = get_matching_microcode(cpu, ucode_ptr, leftover,
-						 new_rev, &current_size);
-		if (mc_size) {
-			mc_hdr  = patch;
-			new_mc  = patch;
-			new_rev = mc_hdr->patch_id;
-			goto out_ok;
-		}
+		crnt_size = verify_and_add_patch(cpu, fw, leftover);
+		if (crnt_size < 0)
+			return ret;
 
-		ucode_ptr += current_size;
-		leftover  -= current_size;
+		fw	 += crnt_size;
+		leftover -= crnt_size;
 	}
 
-	if (!new_mc) {
-		state = UCODE_NFOUND;
-		goto free_table;
-	}
-
-out_ok:
-	uci->mc = new_mc;
-	state = UCODE_OK;
-	pr_debug("CPU%d update ucode (0x%08x -> 0x%08x)\n",
-		 cpu, uci->cpu_sig.rev, new_rev);
-
-free_table:
-	free_equiv_cpu_table();
-
-out:
-	return state;
+	return UCODE_OK;
 }
 
 /*
@@ -401,7 +402,7 @@ out:
  *
  * This legacy file is always smaller than 2K in size.
  *
- * Starting at family 15h they are in family specific firmware files:
+ * Beginning with family 15h, they are in family-specific firmware files:
  *
  *    amd-ucode/microcode_amd_fam15h.bin
  *    amd-ucode/microcode_amd_fam16h.bin
@@ -413,9 +414,13 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
 					      bool refresh_fw)
 {
 	char fw_name[36] = "amd-ucode/microcode_amd.bin";
-	const struct firmware *fw;
-	enum ucode_state ret = UCODE_NFOUND;
 	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);
@@ -431,12 +436,17 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device,
 		goto fw_release;
 	}
 
-	ret = generic_load_microcode(cpu, fw->data, fw->size);
+	/* free old equiv table */
+	free_equiv_cpu_table();
+
+	ret = load_microcode_amd(cpu, fw->data, fw->size);
+	if (ret != UCODE_OK)
+		cleanup();
 
-fw_release:
+ fw_release:
 	release_firmware(fw);
 
-out:
+ out:
 	return ret;
 }
 
@@ -470,14 +480,10 @@ struct microcode_ops * __init init_amd_microcode(void)
 		return NULL;
 	}
 
-	patch = (void *)get_zeroed_page(GFP_KERNEL);
-	if (!patch)
-		return NULL;
-
 	return &microcode_amd_ops;
 }
 
 void __exit exit_amd_microcode(void)
 {
-	free_page((unsigned long)patch);
+	cleanup();
 }