Commit 084189a8 authored Apr 14, 2011 by Richard Weinberger Committed by Linus Torvalds Apr 14, 2011

um: disable CONFIG_CMPXCHG_LOCAL



Commit 8a5ec0ba "Lockless (and preemptless) fastpaths for slub" makes use
of this_cpu_cmpxchg_double() which needs this_cpu_cmpxchg16b_emu() on
x86_64.  Implementing cmpxchg16b emulation for UML would introduce too
much complexity.  So just disable it.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reported-by: Sergei Trofimovich <slyich@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 6d56dad3

arch/um/Kconfig.x86

+4 −0

Original line number	Diff line number	Diff line
		@@ -4,6 +4,10 @@ menu "UML-specific options"

		menu "Host processor type and features"

		config CMPXCHG_LOCAL
		bool
		default n

		source "arch/x86/Kconfig.cpu"

		endmenu