[uml-devel] [PATCH 4/9] UML - Mark SMP on UML/x86_64 as broken

[Jeff D. <jd...@ad...>]

Noticed by Al Viro - SMP on x86_64 is fundamentally broken due to
UML's reuse of the host arch's percpu stuff.  This is OK on x86, but
the x86_64 pda stuff just won't work for UML.

Signed-off-by: Jeff Dike <jd...@ad...>

Index: linux-2.6.13-rc6/arch/um/Kconfig
===================================================================
--- linux-2.6.13-rc6.orig/arch/um/Kconfig	2005-08-15 12:03:07.000000000 -0400
+++ linux-2.6.13-rc6/arch/um/Kconfig	2005-08-15 14:04:23.000000000 -0400
@@ -196,7 +196,7 @@
 config SMP
 	bool "Symmetric multi-processing support (EXPERIMENTAL)"
 	default n
-	depends on MODE_TT && EXPERIMENTAL
+	depends on (MODE_TT && EXPERIMENTAL && !SMP_BROKEN) || (BROKEN && SMP_BROKEN)
 	help
 	This option enables UML SMP support.
 	It is NOT related to having a real SMP box. Not directly, at least.
Index: linux-2.6.13-rc6/arch/um/Kconfig_x86_64
===================================================================
--- linux-2.6.13-rc6.orig/arch/um/Kconfig_x86_64	2005-08-08 12:11:18.000000000 -0400
+++ linux-2.6.13-rc6/arch/um/Kconfig_x86_64	2005-08-15 14:04:27.000000000 -0400
@@ -33,3 +33,7 @@
 config ARCH_REUSE_HOST_VSYSCALL_AREA
 	bool
 	default n
+
+config SMP_BROKEN
+	bool
+	default y