4 files changed, 52 insertions, 8 deletions

diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt
index 0ee5e3b212f3..fa2bed07d21e 100644
--- a/Documentation/x86/x86_64/boot-options.txt
+++ b/Documentation/x86/x86_64/boot-options.txt
@@ -7,12 +7,36 @@ Machine check
 
    Please see Documentation/x86/x86_64/machinecheck for sysfs runtime tunables.
 
-   mce=off disable machine check
-   mce=bootlog Enable logging of machine checks left over from booting.
-               Disabled by default on AMD because some BIOS leave bogus ones.
-               If your BIOS doesn't do that it's a good idea to enable though
-               to make sure you log even machine check events that result
-               in a reboot. On Intel systems it is enabled by default.
+   mce=off
+                Disable machine check
+   mce=no_cmci
+                Disable CMCI(Corrected Machine Check Interrupt) that
+                Intel processor supports.  Usually this disablement is
+                not recommended, but it might be handy if your hardware
+                is misbehaving.
+                Note that you'll get more problems without CMCI than with
+                due to the shared banks, i.e. you might get duplicated
+                error logs.
+   mce=dont_log_ce
+                Don't make logs for corrected errors.  All events reported
+                as corrected are silently cleared by OS.
+                This option will be useful if you have no interest in any
+                of corrected errors.
+   mce=ignore_ce
+                Disable features for corrected errors, e.g. polling timer
+                and CMCI.  All events reported as corrected are not cleared
+                by OS and remained in its error banks.
+                Usually this disablement is not recommended, however if
+                there is an agent checking/clearing corrected errors
+                (e.g. BIOS or hardware monitoring applications), conflicting
+                with OS's error handling, and you cannot deactivate the agent,
+                then this option will be a help.
+   mce=bootlog
+                Enable logging of machine checks left over from booting.
+                Disabled by default on AMD because some BIOS leave bogus ones.
+                If your BIOS doesn't do that it's a good idea to enable though
+                to make sure you log even machine check events that result
+                in a reboot. On Intel systems it is enabled by default.
    mce=nobootlog
                 Disable boot machine check logging.
    mce=tolerancelevel[,monarchtimeout] (number,number)
diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 82978ad12072..540a466e50f5 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -119,6 +119,8 @@ extern void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
 #define MAX_NR_BANKS (MCE_EXTENDED_BANK - 1)
 
 #ifdef CONFIG_X86_MCE_INTEL
+extern int mce_cmci_disabled;
+extern int mce_ignore_ce;
 void mce_intel_feature_init(struct cpuinfo_x86 *c);
 void cmci_clear(void);
 void cmci_reenable(void);
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 6a3127ecb5cc..fabba15e4558 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -84,6 +84,9 @@ static int			rip_msr;
 static int                      mce_bootlog = -1;
 static int                      monarch_timeout = -1;
 static int                      mce_panic_timeout;
+static int                      mce_dont_log_ce;
+int                             mce_cmci_disabled;
+int                             mce_ignore_ce;
 int                             mce_ser;
 
 static char                     trigger[128];
@@ -526,7 +529,7 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
                  * Don't get the IP here because it's unlikely to
                  * have anything to do with the actual error location.
                  */
-                if (!(flags & MCP_DONTLOG)) {
+                if (!(flags & MCP_DONTLOG) && !mce_dont_log_ce) {
                         mce_log(&m);
                         add_taint(TAINT_MACHINE_CHECK);
                 }
@@ -1307,6 +1310,9 @@ static void mce_init_timer(void)
         struct timer_list *t = &__get_cpu_var(mce_timer);
         int *n = &__get_cpu_var(next_interval);
 
+        if (mce_ignore_ce)
+                return;
+
         *n = check_interval * HZ;
         if (!*n)
                 return;
@@ -1517,7 +1523,10 @@ static struct miscdevice mce_log_device = {
 };
 
 /*
- * mce=off disables machine check
+ * mce=off Disables machine check
+ * mce=no_cmci Disables CMCI
+ * mce=dont_log_ce Clears corrected events silently, no log created for CEs.
+ * mce=ignore_ce Disables polling and CMCI, corrected events are not cleared.
  * mce=TOLERANCELEVEL[,monarchtimeout] (number, see above)
  *      monarchtimeout is how long to wait for other CPUs on machine
  *      check, or 0 to not wait
@@ -1532,6 +1541,12 @@ static int __init mcheck_enable(char *str)
                 str++;
         if (!strcmp(str, "off"))
                 mce_disabled = 1;
+        else if (!strcmp(str, "no_cmci"))
+                mce_cmci_disabled = 1;
+        else if (!strcmp(str, "dont_log_ce"))
+                mce_dont_log_ce = 1;
+        else if (!strcmp(str, "ignore_ce"))
+                mce_ignore_ce = 1;
         else if (!strcmp(str, "bootlog") || !strcmp(str, "nobootlog"))
                 mce_bootlog = (str[0] == 'b');
         else if (isdigit(str[0])) {
diff --git a/arch/x86/kernel/cpu/mcheck/mce_intel_64.c b/arch/x86/kernel/cpu/mcheck/mce_intel_64.c
index b7c5a2470b40..046087e9808f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_intel_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_intel_64.c
@@ -57,6 +57,9 @@ static int cmci_supported(int *banks)
 {
         u64 cap;
 
+        if (mce_cmci_disabled || mce_ignore_ce)
+                return 0;
+
         /*
          * Vendor check is not strictly needed, but the initial
          * initialization is vendor keyed and this