]> git.karo-electronics.de Git - karo-tx-linux.git/commit
arm64: Fix vdso-offsets.h dependency
authorCatalin Marinas <catalin.marinas@arm.com>
Fri, 8 Jul 2016 11:13:20 +0000 (12:13 +0100)
committerCatalin Marinas <catalin.marinas@arm.com>
Fri, 8 Jul 2016 13:29:18 +0000 (14:29 +0100)
commit90f777beb788d08300f4a1482cb4fd37a401b472
tree1dde16fbc3122b9ab29a60fae912b29460cd5ae1
parent40f87d3114b8a1e730ac8f3dc3cf1efe33124776
arm64: Fix vdso-offsets.h dependency

arch/arm64/kernel/{vdso,signal}.c include generated/vdso-offsets.h, and
therefore the symbol offsets must be generated before these files are
compiled.

The current rules in arm64/kernel/Makefile do not actually enforce
this, because even though $(obj)/vdso is listed as a prerequisite for
vdso-offsets.h, this does not result in the intended effect of
building the vdso subdirectory (before all the other objects). As a
consequence, depending on the order in which the rules are followed,
vdso-offsets.h is updated or not before arm64/kernel/{vdso,signal}.o
are built. The current rules also impose an unnecessary dependency on
vdso-offsets.h for all arm64/kernel/*.o, resulting in unnecessary
rebuilds.

This patch removes the arch/arm64/kernel/vdso/vdso-offsets.h file
generation, leaving only the include/generated/vdso-offsets.h one. It
adds a forced dependency check of the vdso-offsets.h file in
arch/arm64/kernel/Makefile which, if not up to date according to the
arch/arm64/kernel/vdso/Makefile rules (depending on vdso.so.dbg), will
trigger the vdso/ subdirectory build and vdso-offsets.h re-generation.
Automatic kbuild dependency rules between kernel/{vdso,signal}.c rules
and vdso-offsets.h will guarantee that the vDSO object is built first,
followed by the generated symbol offsets header file.

Reported-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/kernel/Makefile
arch/arm64/kernel/vdso/Makefile