RAS: Add a Corrected Errors Collector

Introduce a simple data structure for collecting correctable errors
along with accessors. More detailed description in the code itself.

The error decoding is done with the decoding chain now and
mce_first_notifier() gets to see the error first and the CEC decides
whether to log it and then the rest of the chain doesn't hear about it -
basically the main reason for the CE collector - or to continue running
the notifiers.

When the CEC hits the action threshold, it will try to soft-offine the
page containing the ECC and then the whole decoding chain gets to see
the error.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170327093304.10683-5-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 2ba45caabada..927b8b8854cd 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3172,6 +3172,12 @@
         ramdisk_size=   [RAM] Sizes of RAM disks in kilobytes
                         See Documentation/blockdev/ramdisk.txt.
 
+        ras=option[,option,...] [KNL] RAS-specific options
+
+                cec_disable     [X86]
+                                Disable the Correctable Errors Collector,
+                                see CONFIG_RAS_CEC help text.
+
         rcu_nocbs=      [KNL]
                         The argument is a cpu list, as described above.