[PATCH] arm: Disable kmemleak on XIP kernels

From: Vincenzo Frascino
Date: Fri Jan 10 2020 - 07:33:01 EST


Kmemleak relies on specific symbols to register the read only data
during init (e.g. __start_ro_after_init).
Trying to build an XIP kernel on arm results in the linking error
reported below because when this option is selected read only data
after init are not allowed since .data is read only (.rodata).

arm-linux-gnueabihf-ld: mm/kmemleak.o: in function `kmemleak_init':
kmemleak.c:(.init.text+0x148): undefined reference to `__end_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x14c):
undefined reference to `__end_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x150):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x156):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x162):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x16a):
undefined reference to `__start_ro_after_init'
linux/Makefile:1078: recipe for target 'vmlinux' failed

Fix the issue enabling kmemleak only on non XIP kernels.

Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
---
arch/arm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index bc99582bdc85..99a3e14e62bd 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -73,7 +73,7 @@ config ARM
select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
select HAVE_CONTEXT_TRACKING
select HAVE_C_RECORDMCOUNT
- select HAVE_DEBUG_KMEMLEAK
+ select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
select HAVE_DMA_CONTIGUOUS if MMU
select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
--
2.24.1