[PATCH 2/2] powerpc/vdso32: link vdso64 with linker
From: Nick Desaulniers <hidden>
Date: 2020-09-01 22:25:45
Also in:
linuxppc-dev
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Rather than invoke the compiler as the driver, use the linker. That way
we can check --orphan-handling=warn support correctly, as cc-ldoption
was removed in
commit 055efab3120b ("kbuild: drop support for cc-ldoption").
Requires dropping the .got section. I couldn't find how it was used in
the vdso32.
Fixes: commit f2af201002a8 ("powerpc/build: vdso linker warning for orphan sections")
Link: https://lore.kernel.org/lkml/CAKwvOdnn3wxYdJomvnveyD_njwRku3fABWT_bS92duihhywLJQ@mail.gmail.com/ (local)
Signed-off-by: Nick Desaulniers <redacted>
---
Not sure removing .got is a good idea or not. Otherwise I observe the
following link error:
powerpc-linux-gnu-ld: warning: orphan section `.got' from `arch/powerpc/kernel/vdso32/sigtramp.o' being placed in section `.got'
powerpc-linux-gnu-ld: _GLOBAL_OFFSET_TABLE_ not defined in linker created .got
powerpc-linux-gnu-ld: final link failed: bad value
sigtramp.c doesn't mention anything from the GOT AFAICT, and doesn't
look like it contains relocations that do, so I'm not sure where
references to _GLOBAL_OFFSET_TABLE_ are coming from.
arch/powerpc/kernel/vdso32/Makefile | 7 +++++--
arch/powerpc/kernel/vdso32/vdso32.lds.S | 3 ++-
2 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 87ab1152d5ce..611a5951945a 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile@@ -27,6 +27,9 @@ UBSAN_SANITIZE := n ccflags-y := -shared -fno-common -fno-builtin -nostdlib \ -Wl,-soname=linux-vdso32.so.1 -Wl,--hash-style=both asflags-y := -D__VDSO32__ -s +ldflags-y := -shared -soname linux-vdso32.so.1 \ + $(call ld-option, --eh-frame-hdr) \ + $(call ld-option, --orphan-handling=warn) -T obj-y += vdso32_wrapper.o extra-y += vdso32.lds
@@ -49,8 +52,8 @@ $(obj-vdso32): %.o: %.S FORCE $(call if_changed_dep,vdso32as) # actual build commands -quiet_cmd_vdso32ld = VDSO32L $@ - cmd_vdso32ld = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) +quiet_cmd_vdso32ld = LD $@ + cmd_vdso32ld = $(cmd_ld) quiet_cmd_vdso32as = VDSO32A $@ cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) -c -o $@ $<
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 4c985467a668..0ccdebad18b8 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S@@ -61,7 +61,6 @@ SECTIONS .fixup : { *(.fixup) } .dynamic : { *(.dynamic) } :text :dynamic - .got : { *(.got) } :text .plt : { *(.plt) } _end = .;
@@ -108,7 +107,9 @@ SECTIONS .debug_varnames 0 : { *(.debug_varnames) } /DISCARD/ : { + *(.got) *(.note.GNU-stack) + *(.branch_lt) *(.data .data.* .gnu.linkonce.d.* .sdata*) *(.bss .sbss .dynbss .dynsbss) *(.glink .iplt .plt .rela*)
--
2.28.0.402.g5ffc5be6b7-goog