1 files changed, 10 insertions, 1 deletions

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index 018d68e3184..e09a6b73a1a 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -321,8 +321,17 @@ config X86_XADD
         depends on X86_32 && !M386
 
 config X86_PPRO_FENCE
-        def_bool y
+        bool "PentiumPro memory ordering errata workaround"
         depends on M686 || M586MMX || M586TSC || M586 || M486 || M386 || MGEODEGX1
+        help
+          Old PentiumPro multiprocessor systems had errata that could cause memory
+          operations to violate the x86 ordering standard in rare cases. Enabling this
+          option will attempt to work around some (but not all) occurances of
+          this problem, at the cost of much heavier spinlock and memory barrier
+          operations.
+
+          If unsure, say n here. Even distro kernels should think twice before enabling
+          this: there are few systems, and an unlikely bug.
 
 config X86_F00F_BUG
         def_bool y