Commit 8871331b authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: build: disallow invalid PAE40 + 4K page config 



The config option being built was
| CONFIG_ARC_MMU_V4=y
| CONFIG_ARC_PAGE_SIZE_4K=y
| CONFIG_HIGHMEM=y
| CONFIG_ARC_HAS_PAE40=y

This was hitting a BUILD_BUG_ON() since a 4K page can't hoist 1k, 8-byte
PTE entries (8 byte due to PAE40). BUILD_BUG_ON() is a good last ditch
resort, but such a config needs to be disallowed explicitly in Kconfig.

Side-note: the actual fix is single liner dependency, but while at it
cleaned out a few things:
 - 4K dependency on MMU v3 or v4 is always true, since 288ff7de
   ("ARC: retire MMUv1 and MMUv2 support")
 - PAE40 dependency in on MMU ver not really ISA, although that follows
   eventually.

Reported-by: default avatarkernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409160223.xydgucbY-lkp@intel.com/


Signed-off-by: default avatarVineet Gupta <vgupta@kernel.org>
parent c0cd2941

arch/arc/Kconfig

+2 −2
Original line number Diff line number Diff line
@@ -297,7 +297,6 @@ config ARC_PAGE_SIZE_16K 
config ARC_PAGE_SIZE_4K

	bool "4KB"

	select HAVE_PAGE_SIZE_4KB

	depends on ARC_MMU_V3 || ARC_MMU_V4



endchoice
@@ -474,7 +473,8 @@ config HIGHMEM 


config ARC_HAS_PAE40

	bool "Support for the 40-bit Physical Address Extension"

	depends on ISA_ARCV2

	depends on MMU_V4

	depends on !ARC_PAGE_SIZE_4K

	select HIGHMEM

	select PHYS_ADDR_T_64BIT

	help