[PATCH] kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL

[PATCH] kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL

[Nicholas Piggin]

The CRC code for asm exports grabs the preprocessed asm, finds the
___EXPORT_SYMBOL and turns those into EXPORT_SYMBOL in a C program
that can be preprocessed and parsed to create the CRC signatures from
the type.

The existing regex matching and replacement is too strict, and doesn't
deal well with whitespace among other things. The line
" EXPORT_SYMBOL(sym)" in a .S file would not match due to initial
whitespace, for example, which resulted in x86's ___preempt_schedule
failing to get CRCs.

Reported-by: Philip Müller <philm@manjaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 scripts/Makefile.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 3e223c2..7675d11 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -332,8 +332,8 @@ cmd_gensymtypes_S =                                                         \
     (echo "\#include <linux/kernel.h>" ;                                    \
      echo "\#include <asm/asm-prototypes.h>" ;                              \
     $(CPP) $(a_flags) $< |                                                  \
-     grep ^___EXPORT_SYMBOL |                                               \
-     sed 's/___EXPORT_SYMBOL \([a-zA-Z0-9_]*\),.*/EXPORT_SYMBOL(\1);/' ) |  \
+     grep "\<___EXPORT_SYMBOL\>" |                                          \
+     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
     $(GENKSYMS) $(if $(1), -T $(2))                                         \
      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
-- 
2.10.2

Re: [PATCH] kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL

[Michal Marek]

Dne 9.11.2016 v 05:34 Nicholas Piggin napsal(a):
> The CRC code for asm exports grabs the preprocessed asm, finds the
> ___EXPORT_SYMBOL and turns those into EXPORT_SYMBOL in a C program
> that can be preprocessed and parsed to create the CRC signatures from
> the type.
> 
> The existing regex matching and replacement is too strict, and doesn't
> deal well with whitespace among other things. The line
> " EXPORT_SYMBOL(sym)" in a .S file would not match due to initial
> whitespace, for example, which resulted in x86's ___preempt_schedule
> failing to get CRCs.
> 
> Reported-by: Philip Müller <philm@manjaro.org>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

Applied to kbuild.git#rc-fixes.

Michal