[PATCH -v3 0/6] x86, MCE, AMD: Hardware MCE injection

[PATCH -v3 0/6] x86, MCE, AMD: Hardware MCE injection

[Borislav Petkov]

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

Hi,

this new set version moves the whole interface to debugfs since it
belongs there in the first place. Remaining functionality unchanged.

Changelog:

v2: only small changes from the last submission
(http://lkml.org/lkml/2011/4/15/171) so that we can have valid
MCG_STATUS values and don't choke on severity sanity checking.

v1: Initial submission.


Thanks.

[PATCH -v3 1/6] x86, MCE: Add a HW injection flag

[Borislav Petkov]

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

Add an mce->inject_flag to denote that we're doing HW injection.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/include/asm/mce.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index eb16e94..a2e3dcf 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -49,6 +49,7 @@
 #define MCJ_CTX_IRQ		2    /* inject context: IRQ */
 #define MCJ_NMI_BROADCAST	4    /* do NMI broadcasting */
 #define MCJ_EXCEPTION		8    /* raise as exception */
+#define MCJ_HW_INJECT		16   /* do a HW MCE inject, i.e. INT18 */
 
 /* Fields are zero when not available */
 struct mce {
-- 
1.7.4.rc2

Re: [PATCH -v3 1/6] x86, MCE: Add a HW injection flag

[Hidetoshi Seto]

(2011/05/10 3:35), Borislav Petkov wrote:
> From: Borislav Petkov <borislav.petkov@amd.com>
> 
> Add an mce->inject_flag to denote that we're doing HW injection.
> 
> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
> Acked-by: Ingo Molnar <mingo@elte.hu>
> ---
>  arch/x86/include/asm/mce.h |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
> index eb16e94..a2e3dcf 100644
> --- a/arch/x86/include/asm/mce.h
> +++ b/arch/x86/include/asm/mce.h
> @@ -49,6 +49,7 @@
>  #define MCJ_CTX_IRQ		2    /* inject context: IRQ */
>  #define MCJ_NMI_BROADCAST	4    /* do NMI broadcasting */
>  #define MCJ_EXCEPTION		8    /* raise as exception */
> +#define MCJ_HW_INJECT		16   /* do a HW MCE inject, i.e. INT18 */
>  
>  /* Fields are zero when not available */
>  struct mce {

IMHO, we should have better name for this feature; using wrmsr + int$18 is not
the only way to inject mce event to HW. I'd like to suggest MCJ_AMD_HW_INJECT,
MCJ_USE_WRMSR or so instead. Then we can have MCJ_USE_APEI_EINJ and so on, for
various way of MCE injection.


Thanks,
H.Seto

Re: [PATCH -v3 1/6] x86, MCE: Add a HW injection flag

[Borislav Petkov]

On Mon, May 09, 2011 at 11:29:27PM -0400, Hidetoshi Seto wrote:
> (2011/05/10 3:35), Borislav Petkov wrote:
> > From: Borislav Petkov <borislav.petkov@amd.com>
> > 
> > Add an mce->inject_flag to denote that we're doing HW injection.
> > 
> > Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
> > Acked-by: Ingo Molnar <mingo@elte.hu>
> > ---
> >  arch/x86/include/asm/mce.h |    1 +
> >  1 files changed, 1 insertions(+), 0 deletions(-)
> > 
> > diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
> > index eb16e94..a2e3dcf 100644
> > --- a/arch/x86/include/asm/mce.h
> > +++ b/arch/x86/include/asm/mce.h
> > @@ -49,6 +49,7 @@
> >  #define MCJ_CTX_IRQ		2    /* inject context: IRQ */
> >  #define MCJ_NMI_BROADCAST	4    /* do NMI broadcasting */
> >  #define MCJ_EXCEPTION		8    /* raise as exception */
> > +#define MCJ_HW_INJECT		16   /* do a HW MCE inject, i.e. INT18 */
> >  
> >  /* Fields are zero when not available */
> >  struct mce {
> 
> IMHO, we should have better name for this feature; using wrmsr + int$18 is not
> the only way to inject mce event to HW. I'd like to suggest MCJ_AMD_HW_INJECT,
> MCJ_USE_WRMSR or so instead. Then we can have MCJ_USE_APEI_EINJ and so on, for
> various way of MCE injection.

Fair enough, the name might be too generic. Maybe I should change it to
MCJ_HW_MSR_INJECT to denote injecting of hw errors through the MCA MSRs.

-- 
Regards/Gruss,
Boris.

Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach
General Managers: Alberto Bozzo, Andrew Bowd
Registration: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632

[PATCH -v3 2/6] x86, MCE: Export mce_get_debugfs_dir

[Borislav Petkov]

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

This is needed for external users of the same debugfs toplevel dir.

Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 arch/x86/include/asm/mce.h                |    1 +
 arch/x86/kernel/cpu/mcheck/mce-internal.h |    1 -
 arch/x86/kernel/cpu/mcheck/mce.c          |    1 +
 3 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index a2e3dcf..1c9c7be 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -241,5 +241,6 @@ struct cper_sec_mem_err;
 extern void apei_mce_report_mem_error(int corrected,
 				      struct cper_sec_mem_err *mem_err);
 
+struct dentry *mce_get_debugfs_dir(void);
 #endif /* __KERNEL__ */
 #endif /* _ASM_X86_MCE_H */
diff --git a/arch/x86/kernel/cpu/mcheck/mce-internal.h b/arch/x86/kernel/cpu/mcheck/mce-internal.h
index fefcc69..660a9e1 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-internal.h
+++ b/arch/x86/kernel/cpu/mcheck/mce-internal.h
@@ -22,7 +22,6 @@ struct mce_bank {
 };
 
 int mce_severity(struct mce *a, int tolerant, char **msg);
-struct dentry *mce_get_debugfs_dir(void);
 
 extern int mce_ser;
 
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 3385ea2..262f692 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -2170,6 +2170,7 @@ struct dentry *mce_get_debugfs_dir(void)
 
 	return dmce;
 }
+EXPORT_SYMBOL_GPL(mce_get_debugfs_dir);
 
 static void mce_reset(void)
 {
-- 
1.7.4.rc2

[PATCH -v3 3/6] EDAC, MCE, AMD: Add function to enable direct write to MCE MSRs

[Borislav Petkov]

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

Normally, writing to MCE MSRs causes a #GP. Add a function to enable
direct access to those MSRs.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 drivers/edac/mce_amd_inj.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
index a4987e0..eb36e15 100644
--- a/drivers/edac/mce_amd_inj.c
+++ b/drivers/edac/mce_amd_inj.c
@@ -30,6 +30,30 @@ static struct edac_mce_attr mce_attr_##_name = __ATTR(_name, _mode, _show, _stor
 static struct kobject *mce_kobj;
 
 /*
+ * Caller needs to be make sure this cpu doesn't disappear
+ * from under us, i.e.: get_cpu/put_cpu.
+ */
+static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
+{
+	u32 l, h;
+	int err;
+
+	err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h);
+	if (err) {
+		printk(KERN_ERR "%s: error reading HWCR\n", __func__);
+		return err;
+	}
+
+	enable ? (l |= BIT(18)) : (l &= ~BIT(18));
+
+	err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h);
+	if (err)
+		printk(KERN_ERR "%s: error writing HWCR\n", __func__);
+
+	return err;
+}
+
+/*
  * Collect all the MCi_XXX settings
  */
 static struct mce i_mce;
-- 
1.7.4.rc2

[PATCH -v3 4/6] EDAC, MCE, AMD: Convert to debugfs

[Borislav Petkov]

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

This is a module which is used for debugging MCE decoding paths so its
userspace interface should go to debugfs, where it belongs conceptually.

While at it, add a warning to the Kconfig text that this interface is
unstable and no userspace scripts should rely all too much on it.

Make it so.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 drivers/edac/Kconfig       |    8 +-
 drivers/edac/mce_amd_inj.c |  191 ++++++++++++++++++++------------------------
 2 files changed, 91 insertions(+), 108 deletions(-)

diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index af1a17d..19f85da 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -52,15 +52,17 @@ config EDAC_DECODE_MCE
 	  has been initialized.
 
 config EDAC_MCE_INJ
-	tristate "Simple MCE injection interface over /sysfs"
-	depends on EDAC_DECODE_MCE
+	tristate "Simple debugfs MCE injection interface"
+	depends on EDAC_DECODE_MCE && DEBUG_FS
 	default n
 	help
-	  This is a simple interface to inject MCEs over /sysfs and test
+	  This is a simple interface to inject MCEs over debugfs and test
 	  the MCE decoding code in EDAC.
 
 	  This is currently AMD-only.
 
+	  WARNING: Do not even assume that this interface is staying stable!
+
 config EDAC_MM_EDAC
 	tristate "Main Memory EDAC (Error Detection And Correction) reporting"
 	help
diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
index eb36e15..421c3b5 100644
--- a/drivers/edac/mce_amd_inj.c
+++ b/drivers/edac/mce_amd_inj.c
@@ -10,24 +10,47 @@
  *			Advanced Micro Devices Inc.
  */
 
-#include <linux/kobject.h>
-#include <linux/sysdev.h>
 #include <linux/edac.h>
+#include <linux/debugfs.h>
 #include <asm/mce.h>
 
 #include "mce_amd.h"
 
-struct edac_mce_attr {
-	struct attribute attr;
-	ssize_t (*show) (struct kobject *kobj, struct edac_mce_attr *attr, char *buf);
-	ssize_t (*store)(struct kobject *kobj, struct edac_mce_attr *attr,
-			 const char *buf, size_t count);
-};
+/*
+ * Collect all the MCi_XXX settings
+ */
+static struct mce i_mce;
+static struct dentry *dfs_inj;
+
+#define MCE_INJECT_SET(reg)						\
+static int inj_##reg##_set(void *data, u64 val)				\
+{									\
+	struct mce *m = (struct mce *)data;				\
+									\
+	m->reg = val;							\
+	return 0;							\
+}
+
+MCE_INJECT_SET(status);
+MCE_INJECT_SET(misc);
+MCE_INJECT_SET(addr);
+
+#define MCE_INJECT_GET(reg)						\
+static int inj_##reg##_get(void *data, u64 *val)			\
+{									\
+	struct mce *m = (struct mce *)data;				\
+									\
+	*val = m->reg;							\
+	return 0;							\
+}
 
-#define EDAC_MCE_ATTR(_name, _mode, _show, _store)			\
-static struct edac_mce_attr mce_attr_##_name = __ATTR(_name, _mode, _show, _store)
+MCE_INJECT_GET(status);
+MCE_INJECT_GET(misc);
+MCE_INJECT_GET(addr);
 
-static struct kobject *mce_kobj;
+DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n");
 
 /*
  * Caller needs to be make sure this cpu doesn't disappear
@@ -54,137 +77,95 @@ static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
 }
 
 /*
- * Collect all the MCi_XXX settings
- */
-static struct mce i_mce;
-
-#define MCE_INJECT_STORE(reg)						\
-static ssize_t edac_inject_##reg##_store(struct kobject *kobj,		\
-					 struct edac_mce_attr *attr,	\
-					 const char *data, size_t count)\
-{									\
-	int ret = 0;							\
-	unsigned long value;						\
-									\
-	ret = strict_strtoul(data, 16, &value);				\
-	if (ret < 0)							\
-		printk(KERN_ERR "Error writing MCE " #reg " field.\n");	\
-									\
-	i_mce.reg = value;						\
-									\
-	return count;							\
-}
-
-MCE_INJECT_STORE(status);
-MCE_INJECT_STORE(misc);
-MCE_INJECT_STORE(addr);
-
-#define MCE_INJECT_SHOW(reg)						\
-static ssize_t edac_inject_##reg##_show(struct kobject *kobj,		\
-					struct edac_mce_attr *attr,	\
-					char *buf)			\
-{									\
-	return sprintf(buf, "0x%016llx\n", i_mce.reg);			\
-}
-
-MCE_INJECT_SHOW(status);
-MCE_INJECT_SHOW(misc);
-MCE_INJECT_SHOW(addr);
-
-EDAC_MCE_ATTR(status, 0644, edac_inject_status_show, edac_inject_status_store);
-EDAC_MCE_ATTR(misc, 0644, edac_inject_misc_show, edac_inject_misc_store);
-EDAC_MCE_ATTR(addr, 0644, edac_inject_addr_show, edac_inject_addr_store);
-
-/*
  * This denotes into which bank we're injecting and triggers
  * the injection, at the same time.
  */
-static ssize_t edac_inject_bank_store(struct kobject *kobj,
-				      struct edac_mce_attr *attr,
-				      const char *data, size_t count)
+static int inj_bank_set(void *data, u64 val)
 {
-	int ret = 0;
-	unsigned long value;
-
-	ret = strict_strtoul(data, 10, &value);
-	if (ret < 0) {
-		printk(KERN_ERR "Invalid bank value!\n");
-		return -EINVAL;
-	}
+	struct mce *m = (struct mce *)data;
 
-	if (value > 5)
-		if (boot_cpu_data.x86 != 0x15 || value > 6) {
-			printk(KERN_ERR "Non-existent MCE bank: %lu\n", value);
+	if (val > 5)
+		if (boot_cpu_data.x86 != 0x15 || val > 6) {
+			printk(KERN_ERR "Non-existent MCE bank: %llu\n", val);
 			return -EINVAL;
 		}
 
-	i_mce.bank = value;
+	m->bank = val;
 
-	amd_decode_mce(NULL, 0, &i_mce);
+	amd_decode_mce(NULL, 0, m);
 
-	return count;
+	return 0;
 }
 
-static ssize_t edac_inject_bank_show(struct kobject *kobj,
-				     struct edac_mce_attr *attr, char *buf)
+static int inj_bank_get(void *data, u64 *val)
 {
-	return sprintf(buf, "%d\n", i_mce.bank);
-}
+	struct mce *m = (struct mce *)data;
 
-EDAC_MCE_ATTR(bank, 0644, edac_inject_bank_show, edac_inject_bank_store);
+	*val = m->bank;
+	return 0;
+}
 
-static struct edac_mce_attr *sysfs_attrs[] = { &mce_attr_status, &mce_attr_misc,
-					       &mce_attr_addr, &mce_attr_bank
+DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n");
+
+struct dfs_node {
+	char *name;
+	struct dentry *d;
+	const struct file_operations *fops;
+} dfs_fls[] = {
+	{ .name = "status",	.fops = &status_fops },
+	{ .name = "misc",	.fops = &misc_fops },
+	{ .name = "addr",	.fops = &addr_fops },
+	{ .name = "bank",	.fops = &bank_fops },
 };
 
 static int __init edac_init_mce_inject(void)
 {
-	struct sysdev_class *edac_class = NULL;
-	int i, err = 0;
+	struct dentry *dfs_mce_root;
+	int i;
 
-	edac_class = edac_get_sysfs_class();
-	if (!edac_class)
+	dfs_mce_root = mce_get_debugfs_dir();
+	if (!dfs_mce_root)
 		return -EINVAL;
 
-	mce_kobj = kobject_create_and_add("mce", &edac_class->kset.kobj);
-	if (!mce_kobj) {
-		printk(KERN_ERR "Error creating a mce kset.\n");
-		err = -ENOMEM;
-		goto err_mce_kobj;
-	}
+	dfs_inj = debugfs_create_dir("inject", dfs_mce_root);
+	if (!dfs_inj)
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) {
+		dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name,
+						    S_IRUSR | S_IWUSR,
+						    dfs_inj,
+						    &i_mce,
+						    dfs_fls[i].fops);
+
+		if (!dfs_fls[i].d)
+			goto err_dfs_add;
 
-	for (i = 0; i < ARRAY_SIZE(sysfs_attrs); i++) {
-		err = sysfs_create_file(mce_kobj, &sysfs_attrs[i]->attr);
-		if (err) {
-			printk(KERN_ERR "Error creating %s in sysfs.\n",
-					sysfs_attrs[i]->attr.name);
-			goto err_sysfs_create;
-		}
 	}
+
 	return 0;
 
-err_sysfs_create:
+err_dfs_add:
 	while (--i >= 0)
-		sysfs_remove_file(mce_kobj, &sysfs_attrs[i]->attr);
+		debugfs_remove(dfs_fls[i].d);
 
-	kobject_del(mce_kobj);
+	debugfs_remove(dfs_inj);
+	dfs_inj = NULL;
 
-err_mce_kobj:
-	edac_put_sysfs_class();
-
-	return err;
+	return -ENOMEM;
 }
 
 static void __exit edac_exit_mce_inject(void)
 {
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(sysfs_attrs); i++)
-		sysfs_remove_file(mce_kobj, &sysfs_attrs[i]->attr);
+	for (i = 0; i < ARRAY_SIZE(dfs_fls); i++)
+		debugfs_remove(dfs_fls[i].d);
 
-	kobject_del(mce_kobj);
+	memset(&dfs_fls, 0, sizeof(dfs_fls));
 
-	edac_put_sysfs_class();
+	debugfs_remove(dfs_inj);
+	dfs_inj = NULL;
 }
 
 module_init(edac_init_mce_inject);
-- 
1.7.4.rc2

[PATCH -v3 5/6] EDAC, MCE, AMD: Add attributes needed for HW injection

[Borislav Petkov]

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

hw_inject denotes whether we want to do a hardware or a software
injection and, in the case of hardware injection, we want to do that on
a particular cpu, thus the second 'cpu' attribute.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 drivers/edac/mce_amd_inj.c |   57 ++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 57 insertions(+), 0 deletions(-)

diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
index 421c3b5..592871f 100644
--- a/drivers/edac/mce_amd_inj.c
+++ b/drivers/edac/mce_amd_inj.c
@@ -77,6 +77,61 @@ static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
 }
 
 /*
+ * HW or SW injection
+ */
+static int hw_inj_get(void *data, u64 *val)
+{
+	struct mce *m = (struct mce *)data;
+
+	*val = !!(m->inject_flags & MCJ_HW_INJECT);
+
+	return 0;
+}
+
+static int hw_inj_set(void *data, u64 val)
+{
+	struct mce *m = (struct mce *)data;
+
+	switch (val) {
+	case 0:
+		m->inject_flags &= (u8)~MCJ_HW_INJECT;
+		break;
+
+	case 1:
+		m->inject_flags |= MCJ_HW_INJECT;
+		break;
+
+	default:
+		printk(KERN_ERR "%s: Only 0 or 1 allowed!\n", __func__);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(hw_inj_fops, hw_inj_get, hw_inj_set, "%llu\n");
+
+/*
+ * On which CPU to inject?
+ */
+
+MCE_INJECT_GET(extcpu);
+
+
+static int inj_extcpu_set(void *data, u64 val)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (val >= num_online_cpus()) {
+		printk(KERN_ERR "%s: Non-existent CPU: %llu\n", __func__, val);
+		return -EINVAL;
+	}
+	m->extcpu = val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n");
+
+/*
  * This denotes into which bank we're injecting and triggers
  * the injection, at the same time.
  */
@@ -116,6 +171,8 @@ struct dfs_node {
 	{ .name = "misc",	.fops = &misc_fops },
 	{ .name = "addr",	.fops = &addr_fops },
 	{ .name = "bank",	.fops = &bank_fops },
+	{ .name = "hw_inject",	.fops = &hw_inj_fops },
+	{ .name = "cpu",	.fops = &extcpu_fops },
 };
 
 static int __init edac_init_mce_inject(void)
-- 
1.7.4.rc2

[PATCH -v3 6/6] EDAC, MCE, AMD: Add an injector function

[Borislav Petkov]

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

Selectively inject either a real MCE or a sw-only version which
exercises the decoding code only. The hardware-injected MCE triggers a
machine check exception (#MC) so that the MCE handler can be bothered to
do something too.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
---
 drivers/edac/mce_amd_inj.c |   50 ++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
index 592871f..45e8122 100644
--- a/drivers/edac/mce_amd_inj.c
+++ b/drivers/edac/mce_amd_inj.c
@@ -131,6 +131,53 @@ static int inj_extcpu_set(void *data, u64 val)
 
 DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n");
 
+static void trigger_mce(void *info)
+{
+	asm volatile("int $18");
+}
+
+static void do_inject(void)
+{
+	u64 mcg_status = 0;
+	unsigned int cpu = i_mce.extcpu;
+	int this_cpu;
+	u8 b = i_mce.bank;
+
+	if (!(i_mce.inject_flags & MCJ_HW_INJECT)) {
+		amd_decode_mce(NULL, 0, &i_mce);
+		return;
+	}
+
+	/* prep MCE global settings for the injection */
+	mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV;
+
+	if (!(i_mce.status & MCI_STATUS_PCC))
+		mcg_status |= MCG_STATUS_RIPV;
+
+	this_cpu = get_cpu();
+
+	toggle_hw_mce_inject(cpu, true);
+
+	wrmsr_on_cpu(cpu, MSR_IA32_MCG_STATUS,
+		     (u32)mcg_status, (u32)(mcg_status >> 32));
+
+	wrmsr_on_cpu(cpu, MSR_IA32_MCx_STATUS(b),
+		     (u32)i_mce.status, (u32)(i_mce.status >> 32));
+
+	wrmsr_on_cpu(cpu, MSR_IA32_MCx_ADDR(b),
+		     (u32)i_mce.addr, (u32)(i_mce.addr >> 32));
+
+	wrmsr_on_cpu(cpu, MSR_IA32_MCx_MISC(b),
+		     (u32)i_mce.misc, (u32)(i_mce.misc >> 32));
+
+	toggle_hw_mce_inject(cpu, false);
+
+	smp_call_function_single(cpu, trigger_mce, NULL, 0);
+
+	put_cpu();
+
+}
+
 /*
  * This denotes into which bank we're injecting and triggers
  * the injection, at the same time.
@@ -146,8 +193,7 @@ static int inj_bank_set(void *data, u64 val)
 		}
 
 	m->bank = val;
-
-	amd_decode_mce(NULL, 0, m);
+	do_inject();
 
 	return 0;
 }
-- 
1.7.4.rc2