1 files changed, 26 insertions, 6 deletions

diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index f395fd537c5c..f7169edfbeab 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -172,13 +172,33 @@ config IOMMU_LEAK
           Add a simple leak tracer to the IOMMU code. This is useful when you
           are debugging a buggy device driver that leaks IOMMU mappings.
 
-config PAGE_FAULT_HANDLERS
-        bool "Custom page fault handlers"
-        depends on DEBUG_KERNEL
+config MMIOTRACE_HOOKS
+        bool
+
+config MMIOTRACE
+        bool "Memory mapped IO tracing"
+        depends on DEBUG_KERNEL && PCI
+        select TRACING
+        select MMIOTRACE_HOOKS
+        default y
+        help
+          Mmiotrace traces Memory Mapped I/O access and is meant for
+          debugging and reverse engineering. It is called from the ioremap
+          implementation and works via page faults. Tracing is disabled by
+          default and can be enabled at run-time.
+
+          See Documentation/tracers/mmiotrace.txt.
+          If you are not helping to develop drivers, say N.
+
+config MMIOTRACE_TEST
+        tristate "Test module for mmiotrace"
+        depends on MMIOTRACE && m
         help
-          Allow the use of custom page fault handlers. A kernel module may
-          register a function that is called on every page fault. Custom
-          handlers are used by some debugging and reverse engineering tools.
+          This is a dumb module for testing mmiotrace. It is very dangerous
+          as it will write garbage to IO memory starting at a given address.
+          However, it should be safe to use on e.g. unused portion of VRAM.
+
+          Say N, unless you absolutely know what you are doing.
 
 #
 # IO delay types: