[PATCH] fbdev: have CONFIG_FB_DEFERRED_IO depend on CONFIG_MMU

[Lorenzo Stoakes]

Frame buffer deferred I/O is entirely reliant on the page faulting
mechanism (and thus, an MMU) to function.

Express this dependency in the Kconfig, as otherwise randconfig could
generate invalid configurations resulting in build errors.

Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202502020030.MnEJ847Z-lkp@xxxxxxxxx/
---
 drivers/video/fbdev/core/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/video/fbdev/core/Kconfig b/drivers/video/fbdev/core/Kconfig
index d554d8c543d4..154804914680 100644
--- a/drivers/video/fbdev/core/Kconfig
+++ b/drivers/video/fbdev/core/Kconfig
@@ -135,6 +135,7 @@ config FB_SYSMEM_FOPS
 config FB_DEFERRED_IO
 	bool
 	depends on FB_CORE
+	depends on MMU

 config FB_DMAMEM_HELPERS
 	bool
--
2.48.1