This is a note to let you know that I've just added the patch titled
objtool: Fix seg fault with gold linker
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: objtool-fix-seg-fault-with-gold-linker.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 2a0098d70640dda192a79966c14d449e7a34d675 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf jpoimboe@redhat.com Date: Mon, 15 Jan 2018 08:17:07 -0600 Subject: objtool: Fix seg fault with gold linker
From: Josh Poimboeuf jpoimboe@redhat.com
commit 2a0098d70640dda192a79966c14d449e7a34d675 upstream.
Objtool segfaults when the gold linker is used with CONFIG_MODVERSIONS=y and CONFIG_UNWINDER_ORC=y.
With CONFIG_MODVERSIONS=y, the .o file gets passed to the linker before being passed to objtool. The gold linker seems to strip unused ELF symbols by default, which confuses objtool and causes the seg fault when it's trying to generate ORC metadata.
Objtool should really be running immediately after GCC anyway, without a linker call in between. Change the makefile ordering so that objtool is called before the linker.
Reported-and-tested-by: Markus M4rkusXXL@web.de Signed-off-by: Josh Poimboeuf jpoimboe@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Link: http://lkml.kernel.org/r/355f04da33581f4a3bf82e5b512973624a1e23a2.1516025651... Signed-off-by: Ingo Molnar mingo@kernel.org Cc: Guenter Roeck linux@roeck-us.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- scripts/Makefile.build | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
--- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -270,12 +270,18 @@ else objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable) endif
+ifdef CONFIG_MODVERSIONS +objtool_o = $(@D)/.tmp_$(@F) +else +objtool_o = $(@) +endif + # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file cmd_objtool = $(if $(patsubst y%,, \ $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ - $(__objtool_obj) $(objtool_args) "$(@)";) + $(__objtool_obj) $(objtool_args) "$(objtool_o)";) objtool_obj = $(if $(patsubst y%,, \ $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \ $(__objtool_obj)) @@ -291,15 +297,15 @@ objtool_dep = $(objtool_obj) \ define rule_cc_o_c $(call echo-cmd,checksrc) $(cmd_checksrc) \ $(call cmd_and_fixdep,cc_o_c) \ - $(cmd_modversions_c) \ $(call echo-cmd,objtool) $(cmd_objtool) \ + $(cmd_modversions_c) \ $(call echo-cmd,record_mcount) $(cmd_record_mcount) endef
define rule_as_o_S $(call cmd_and_fixdep,as_o_S) \ - $(cmd_modversions_S) \ - $(call echo-cmd,objtool) $(cmd_objtool) + $(call echo-cmd,objtool) $(cmd_objtool) \ + $(cmd_modversions_S) endef
# List module undefined symbols (or empty line if not enabled)
Patches currently in stable-queue which might be from jpoimboe@redhat.com are
queue-4.14/objtool-fix-clang-enum-conversion-warning.patch queue-4.14/objtool-fix-seg-fault-with-gold-linker.patch queue-4.14/tools-objtool-makefile-don-t-assume-sync-check.sh-is-executable.patch queue-4.14/objtool-fix-seg-fault-with-clang-compiled-objects.patch queue-4.14/objtool-fix-seg-fault-caused-by-missing-parameter.patch