1 files changed, 11 insertions, 4 deletions

diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index b9e6be00cadf..678e8f192db2 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -6,6 +6,11 @@ only the AMD64 specific ones are listed here.
 Machine check
 
    mce=off disable machine check
+   mce=bootlog Enable logging of machine checks left over from booting.
+               Disabled by default 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.
 
    nomce (for compatibility with i386): same as mce=off
 
@@ -47,7 +52,7 @@ Timing
   notsc
   Don't use the CPU time stamp counter to read the wall time.
   This can be used to work around timing problems on multiprocessor systems
-  with not properly synchronized CPUs. Only useful with a SMP kernel
+  with not properly synchronized CPUs.
 
   report_lost_ticks
   Report when timer interrupts are lost because some code turned off
@@ -74,6 +79,9 @@ Idle loop
   event. This will make the CPUs eat a lot more power, but may be useful
   to get slightly better performance in multiprocessor benchmarks. It also
   makes some profiling using performance counters more accurate.
+  Please note that on systems with MONITOR/MWAIT support (like Intel EM64T
+  CPUs) this option has no performance advantage over the normal idle loop.
+  It may also interact badly with hyperthreading.
 
 Rebooting
 
@@ -178,6 +186,5 @@ Debugging
 Misc
 
   noreplacement  Don't replace instructions with more appropiate ones
-                                 for the CPU. This may be useful on asymmetric MP systems
-                                 where some CPU have less capabilities than the others.
-
+                 for the CPU. This may be useful on asymmetric MP systems
+                 where some CPU have less capabilities than the others.