linux-stable/arch/arm64/kernel/vdso
Catalin Marinas 90f777beb7 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>
2016-07-08 14:29:18 +01:00
..
.gitignore arm64: VDSO support 2012-09-17 13:42:09 +01:00
gen_vdso_offsets.sh arm64: VDSO support 2012-09-17 13:42:09 +01:00
gettimeofday.S arm64: vdso: minor ABI fix for clock_getres 2015-02-26 18:13:51 +00:00
Makefile arm64: Fix vdso-offsets.h dependency 2016-07-08 14:29:18 +01:00
note.S arm64: VDSO support 2012-09-17 13:42:09 +01:00
sigreturn.S arm64: VDSO support 2012-09-17 13:42:09 +01:00
vdso.lds.S arm64: vdso: move data page before code pages 2014-07-17 16:18:57 +01:00
vdso.S arm64: vdso: Mark vDSO code as read-only 2016-02-16 18:20:23 +00:00