[PATCH] Make vm86 support optional

This adds an option to remove vm86 support under CONFIG_EMBEDDED.  Saves
about 5k.

This version eliminates most of the #ifdefs of the previous version and
instead uses function stubs in vm86.h.  Also, release_vm86_irqs is moved
from asm-i386/irq.h to a more appropriate home in vm86.h so that the stubs
can live together.

$ size vmlinux-baseline vmlinux-novm86
   text    data     bss     dec     hex filename
2920821  523232  190652 3634705  377611 vmlinux-baseline
2916268  523100  190492 3629860  376324 vmlinux-novm86

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/init/Kconfig b/init/Kconfig
index 9ac522a4013..f8f6929d8f2 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -237,6 +237,16 @@ config UID16
         help
           This enables the legacy 16-bit UID syscall wrappers.
 
+config VM86
+        depends X86
+        default y
+        bool "Enable VM86 support" if EMBEDDED
+        help
+          This option is required by programs like DOSEMU to run 16-bit legacy
+          code on X86 processors. It also may be needed by software like
+          XFree86 to initialize some video cards via BIOS. Disabling this
+          option saves about 6k.
+
 config CC_OPTIMIZE_FOR_SIZE
         bool "Optimize for size (Look out for broken compilers!)"
         default y