[PATCHv2] arch/arm/Kconfig: default ARM_MODULE_PLTS to 'y'

From: Anders Roxell
Date: Wed Jan 31 2018 - 15:19:22 EST


While testing multi_v7_defconfig with LOCKDEP enabled, the kernel
fails to load simple modules, as reported by kselftest:

[ 34.107620] test_printf: section 4 reloc 2 sym 'memset': relocation
28 out of range (0xbf046044 -> 0xc109f720)
selftests: printf.sh [FAIL]

The problem that is seen when LOCKDEP is enabled without
ARM_MODULE_PLTS, is that LOCKDEP eats so much memory that the top of the
kernel gets out of reach from the bottom of the module area.

Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
---
arch/arm/Kconfig | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 51c8df561077..8014c8c322df 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1702,6 +1702,7 @@ config ARCH_WANT_GENERAL_HUGETLB
config ARM_MODULE_PLTS
bool "Use PLTs to allow module memory to spill over into vmalloc area"
depends on MODULES
+ default y
help
Allocate PLTs when loading modules so that jumps and calls whose
targets are too far away for their relative offsets to be encoded
--
2.11.0