Re: [PATCH] powerpc/fsl_booke/32: fix build with CONFIG_RANDOMIZE_BASE

Le 13/06/2020 à 18:28, Arseny Solokha a écrit :

quoted

Building the current 5.8 kernel for a e500 machine with
CONFIG_RANDOMIZE_BASE set yields the following failure:

   arch/powerpc/mm/nohash/kaslr_booke.c: In function 'kaslr_early_init':
   arch/powerpc/mm/nohash/kaslr_booke.c:387:2: error: implicit declaration
of function 'flush_icache_range'; did you mean 'flush_tlb_range'?
[-Werror=implicit-function-declaration]

Indeed, including asm/cacheflush.h into kaslr_booke.c fixes the build.

The issue dates back to the introduction of that file and probably went
unnoticed because there's no in-tree defconfig with CONFIG_RANDOMIZE_BASE
set.

I don't get this problem with mpc85xx_defconfig + RELOCATABLE +
RANDOMIZE_BASE.

Ah, OK. So the critical difference between mpc85xx_defconfig and our custom
config is that the former sets CONFIG_BLOCK while ours doesn't. Then we have the
following dependence chain:

arch/powerpc/mm/nohash/kaslr_booke.c
  include/linux/swap.h
    include/linux/memcontrol.h
      include/linux/writeback.h
        include/linux/blk-cgroup.h
          include/linux/blkdev.h

          #ifdef CONFIG_BLOCK
          #include <linux/pagemap.h>
          #endif

          include/linux/pagemap.h
            include/linux/highmem.h
              arch/powerpc/include/asm/cacheflush.h

and that's how the latter doesn't get included in
arch/powerpc/mm/nohash/kaslr_booke.c, because in our config CONFIG_BLOCK is not
defined in the first place.

Arseny

Christophe

quoted

Fixes: 2b0e86cc5de6 ("powerpc/fsl_booke/32: implement KASLR infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Arseny Solokha <redacted>
---
  arch/powerpc/mm/nohash/kaslr_booke.c | 1 +
  1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 4a75f2d9bf0e..bce0e5349978 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c

@@ -14,6 +14,7 @@
  #include <linux/memblock.h>
  #include <linux/libfdt.h>
  #include <linux/crash_core.h>
+#include <asm/cacheflush.h>
  #include <asm/pgalloc.h>
  #include <asm/prom.h>
  #include <asm/kdump.h>