On Tue, 11 May 2021 at 20:51, Jim Cromie <jim.cromie@xxxxxxxxx> wrote: > > The next patch adds DEFINE_DYNAMIC_DEBUG_TABLE(), which broke several > subtrees, including efi, vdso, and some of arch/*/boot/compressed, > with various relocation errors, iirc. > > Avoid those problems by adding a define to suppress the "transparent" > DEFINE_DYNAMIC_DEBUG_TABLE() invocation. I found the x86 problems > myself, lkp@xxxxxxxxx found arm & sparc problems, and may yet find > others. > Given that I was only cc'ed on this patch in isolation, would you mind adding more clarification here? What is DEFINE_DYNAMIC_DEBUG_TABLE() supposed to do, and why is it breaking standalone binaries? > Reported-by: <lkp@xxxxxxxxx> # on [jimc:lkp-test/dyndbg-diet] recently > Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx> > --- > arch/arm/boot/compressed/Makefile | 2 ++ > arch/sparc/vdso/Makefile | 2 ++ > arch/x86/boot/compressed/Makefile | 1 + > arch/x86/entry/vdso/Makefile | 3 +++ > arch/x86/purgatory/Makefile | 1 + > drivers/firmware/efi/libstub/Makefile | 3 ++- > 6 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile > index fd94e27ba4fa..72f056a00ad4 100644 > --- a/arch/arm/boot/compressed/Makefile > +++ b/arch/arm/boot/compressed/Makefile > @@ -82,6 +82,8 @@ compress-$(CONFIG_KERNEL_LZMA) = lzma > compress-$(CONFIG_KERNEL_XZ) = xzkern > compress-$(CONFIG_KERNEL_LZ4) = lz4 > > +KBUILD_CFLAGS += -DNO_DYNAMIC_DEBUG_TABLE > + > libfdt_objs := fdt_rw.o fdt_ro.o fdt_wip.o fdt.o > > ifeq ($(CONFIG_ARM_ATAG_DTB_COMPAT),y) > diff --git a/arch/sparc/vdso/Makefile b/arch/sparc/vdso/Makefile > index c5e1545bc5cf..960ed0fb6804 100644 > --- a/arch/sparc/vdso/Makefile > +++ b/arch/sparc/vdso/Makefile > @@ -30,6 +30,8 @@ obj-y += $(vdso_img_objs) > targets += $(vdso_img_cfiles) > targets += $(vdso_img_sodbg) $(vdso_img-y:%=vdso%.so) > > +KBUILD_CFLAGS += -DNO_DYNAMIC_DEBUG_TABLE > + > CPPFLAGS_vdso.lds += -P -C > > VDSO_LDFLAGS_vdso.lds = -m elf64_sparc -soname linux-vdso.so.1 --no-undefined \ > diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile > index e0bc3988c3fa..ada4eb960d95 100644 > --- a/arch/x86/boot/compressed/Makefile > +++ b/arch/x86/boot/compressed/Makefile > @@ -31,6 +31,7 @@ targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \ > KBUILD_CFLAGS := -m$(BITS) -O2 > KBUILD_CFLAGS += -fno-strict-aliasing -fPIE > KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING > +KBUILD_CFLAGS += -DNO_DYNAMIC_DEBUG_TABLE > cflags-$(CONFIG_X86_32) := -march=i386 > cflags-$(CONFIG_X86_64) := -mcmodel=small -mno-red-zone > KBUILD_CFLAGS += $(cflags-y) > diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile > index 05c4abc2fdfd..619878f2c427 100644 > --- a/arch/x86/entry/vdso/Makefile > +++ b/arch/x86/entry/vdso/Makefile > @@ -29,6 +29,9 @@ vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o > vobjs32-y += vdso32/vclock_gettime.o > vobjs-$(CONFIG_X86_SGX) += vsgx.o > > +# avoid a x86_64_RELATIVE error > +KBUILD_CFLAGS += -DNO_DYNAMIC_DEBUG_TABLE > + > # files to link into kernel > obj-y += vma.o extable.o > KASAN_SANITIZE_vma.o := y > diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile > index 95ea17a9d20c..95ba7b18410f 100644 > --- a/arch/x86/purgatory/Makefile > +++ b/arch/x86/purgatory/Makefile > @@ -35,6 +35,7 @@ PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel > PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0 > PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING > PURGATORY_CFLAGS += -fno-stack-protector > +PURGATORY_CFLAGS += -DNO_DYNAMIC_DEBUG_TABLE > > # Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That > # in turn leaves some undefined symbols like __fentry__ in purgatory and not > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index c23466e05e60..def8febefbd3 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -13,7 +13,8 @@ cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ \ > -Wno-pointer-sign \ > $(call cc-disable-warning, address-of-packed-member) \ > $(call cc-disable-warning, gnu) \ > - -fno-asynchronous-unwind-tables > + -fno-asynchronous-unwind-tables \ > + -DNO_DYNAMIC_DEBUG_TABLE > > # arm64 uses the full KBUILD_CFLAGS so it's necessary to explicitly > # disable the stackleak plugin > -- > 2.31.1 >
