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kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL

PATCH In review Nicholas Piggin 2 participants 2 messages Nov 9, 2016 Kbuild

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Nicholas Piggin

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PATCH 1/1 kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL

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 <[email protected]>
Signed-off-by Nicholas Piggin <[email protected]>
---
 scripts/Makefile.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
scripts/Makefile.build +2 -2
index 3e223c2..7675d11 100644
@@ -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))             \
Signature · 1 line
2.10.2
#1 lore raw

Dne 9.11.2016 v 05:34 Nicholas Piggin napsal(a):

Quoted 5 lines

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.

Quoted 8 lines

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 <[email protected]>
Signed-off-by Nicholas Piggin <[email protected]>

Applied to kbuild.git#rc-fixes.

Michal