On Mon, Jul 18, 2022 at 12:51 PM Ondrej Mosnacek <omosnace@xxxxxxxxxx> wrote: > Similar to the compiler, matching the linker used to compile the kernel > is also important for an external kernel module build. Add code to > detect the linker from the kernel config similar to the existing > compiler detection. > > Speicifically, this fixes kernel module builds under kernels built with > clang and with LTO enabled. > > Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> > --- > tests/module_load/Makefile | 30 +++++++++++++++++++++++------- > 1 file changed, 23 insertions(+), 7 deletions(-) > > diff --git a/tests/module_load/Makefile b/tests/module_load/Makefile > index 272872d..0839532 100644 > --- a/tests/module_load/Makefile > +++ b/tests/module_load/Makefile > @@ -4,12 +4,15 @@ TARGETS = finit_load init_load > LDLIBS += -lselinux > KDIR = /lib/modules/$(shell uname -r)/build > > -# Make sure to use the same compiler as the kernel was built with. > -# If the compilers don't match, the build will fail on unsupported compiler > +# Make sure to use the same compiler+linker as the kernel was built with. > +# If the compilers/linkers don't match, the build could fail on unsupported > # flags and even if not, the resulting module would likely fail to load. > -# If the kernel was compiled with neither GCC nor clang (currently the only > -# supported compilers), fall back to the default compiler and hope for the best. > -# In all cases allow the user to override the compiler via the KCC variable. > +# If the kernel was compiled with a compiler other than GCC or clang or a > +# linker other than ld.bfd or ld.lld, fall back to the default compiler/linker > +# and hope for the best. > +# In all cases allow the user to override the compiler via the KCC/KLD > +# variables. > + > DETECTED_KCC = unknown > ifeq ($(shell grep -qFx CONFIG_CC_IS_GCC=y $(KDIR)/.config && echo true),true) > DETECTED_KCC = gcc > @@ -23,9 +26,22 @@ else > KCC ?= $(CC) > endif > > +DETECTED_KLD = unknown > +ifeq ($(shell grep -qFx CONFIG_LD_IS_BFD=y $(KDIR)/.config && echo true),true) > + DETECTED_KLD = ld.bfd > +endif > +ifeq ($(shell grep -qFx CONFIG_LD_IS_LLD=y $(KDIR)/.config && echo true),true) > + DETECTED_KLD = ld.lld > +endif > +ifneq ($(DETECTED_KLD),unknown) > + KLD ?= $(DETECTED_KLD) > +else > + KLD ?= $(LD) > +endif > + > all: $(TARGETS) > - $(MAKE) -C $(KDIR) CC=$(KCC) M=$(PWD) > + $(MAKE) -C $(KDIR) CC=$(KCC) LD=$(KLD) M=$(PWD) > > clean: > rm -f $(TARGETS) > - $(MAKE) -C $(KDIR) CC=$(KCC) M=$(PWD) clean > + $(MAKE) -C $(KDIR) CC=$(KCC) LD=$(KLD) M=$(PWD) clean > -- > 2.36.1 Whoops, forgot about this patch... Now applied as: https://github.com/SELinuxProject/selinux-testsuite/commit/deeff9d73d9abf84fbb76a019186de06004e121e -- Ondrej Mosnacek Senior Software Engineer, Linux Security - SELinux kernel Red Hat, Inc.
