• Catalin Marinas's avatar
    arm64: Fix vdso-offsets.h dependency · 90f777be
    Catalin Marinas authored
    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: default avatarKevin Brodsky <kevin.brodsky@arm.com>
    Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
    90f777be
Makefile 2.21 KB