1 files changed, 6 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index d7c42319fe1e..d43429f4ced8 100644
--- a/Makefile
+++ b/Makefile
@@ -103,7 +103,7 @@ ifeq ("$(origin O)", "command line")
 endif
 
 ifeq ("$(origin W)", "command line")
-  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := 1
+  export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
 endif
 
 # That's our default target when none is given on the command line
@@ -1274,7 +1274,11 @@ help:
         @echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
         @echo  '  make C=1   [targets] Check all c source with $$CHECK (sparse by default)'
         @echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
-        @echo  '  make W=1   [targets] Enable extra gcc checks'
+        @echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
+        @echo  '                1: warnings which may be relevant and do not occur too often'
+        @echo  '                2: warnings which occur quite often but may still be relevant'
+        @echo  '                3: more obscure warnings, can most likely be ignored'
+
         @echo  ''
         @echo  'Execute "make" or "make all" to build all targets marked with [*] '
         @echo  'For further info see the ./README file'