2 files changed, 8 insertions, 1 deletions

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index bd992c0048f0..fbcc00c6c06e 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -178,6 +178,13 @@ config ARCH_HAS_ILOG2_U64
         bool
         default n
 
+config EMULATED_CMPXCHG
+        bool
+        default y
+        help
+          Sparc32 does not have a CAS instruction like sparc64. cmpxchg()
+          is emulated, and therefore it is not completely atomic.
+
 config SUN_PM
         bool
         default y
diff --git a/drivers/char/drm/Kconfig b/drivers/char/drm/Kconfig
index ef833a1c27eb..0b7ffa5191c6 100644
--- a/drivers/char/drm/Kconfig
+++ b/drivers/char/drm/Kconfig
@@ -6,7 +6,7 @@
 #
 config DRM
         tristate "Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)"
-        depends on (AGP || AGP=n) && PCI
+        depends on (AGP || AGP=n) && PCI && !EMULATED_CMPXCHG
         help
           Kernel-level support for the Direct Rendering Infrastructure (DRI)
           introduced in XFree86 4.0. If you say Y here, you need to select