From 2a0098d70640dda192a79966c14d449e7a34d675 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 15 Jan 2018 08:17:07 -0600 Subject: objtool: Fix seg fault with gold linker 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 Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Link: http://lkml.kernel.org/r/355f04da33581f4a3bf82e5b512973624a1e23a2.1516025651.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- scripts/Makefile.build | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e63af4e19382..6bed45dc2cb1 100644 --- 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) -- cgit From be9fa663d325a102de53c9ab6d00a31dcb36bb73 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 18 Jan 2018 16:33:57 -0800 Subject: scripts/decodecode: fix decoding for AArch64 (arm64) instructions There are a couple of problems with the decodecode script and arm64: 1. AArch64 objdump refuses to disassemble .4byte directives as instructions, insisting that they are data values and displaying them as: a94153f3 .word 0xa94153f3 <-- trapping instruction This is resolved by using the .inst directive instead. 2. Disassembly of branch instructions attempts to provide the target as an offset from a symbol, e.g.: 0: 34000082 cbz w2, 10 <.text+0x10> however this falls foul of the grep -v, which matches lines containing ".text" and ends up removing all branch instructions from the dump. This patch resolves both issues by using the .inst directive for 4-byte quantities on arm64 and stripping the resulting binaries (as is done on arm already) to remove the mapping symbols. Link: http://lkml.kernel.org/r/1506596147-23630-1-git-send-email-will.deacon@arm.com Signed-off-by: Will Deacon Reviewed-by: Dave Martin Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/decodecode | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'scripts') diff --git a/scripts/decodecode b/scripts/decodecode index 438120da1361..5ea071099330 100755 --- a/scripts/decodecode +++ b/scripts/decodecode @@ -59,6 +59,14 @@ disas() { ${CROSS_COMPILE}strip $1.o fi + if [ "$ARCH" = "arm64" ]; then + if [ $width -eq 4 ]; then + type=inst + fi + + ${CROSS_COMPILE}strip $1.o + fi + ${CROSS_COMPILE}objdump $OBJDUMPFLAGS -S $1.o | \ grep -v "/tmp\|Disassembly\|\.text\|^$" > $1.dis 2>&1 } -- cgit From 883d50f56d263f70fd73c0d96b09eb36c34e9305 Mon Sep 17 00:00:00 2001 From: Xi Kangjie Date: Thu, 18 Jan 2018 16:34:00 -0800 Subject: scripts/gdb/linux/tasks.py: fix get_thread_info Since kernel 4.9, the thread_info has been moved into task_struct, no longer locates at the bottom of kernel stack. See commits c65eacbe290b ("sched/core: Allow putting thread_info into task_struct") and 15f4eae70d36 ("x86: Move thread_info into task_struct"). Before fix: (gdb) set $current = $lx_current() (gdb) p $lx_thread_info($current) $1 = {flags = 1470918301} (gdb) p $current.thread_info $2 = {flags = 2147483648} After fix: (gdb) p $lx_thread_info($current) $1 = {flags = 2147483648} (gdb) p $current.thread_info $2 = {flags = 2147483648} Link: http://lkml.kernel.org/r/20180118210159.17223-1-imxikangjie@gmail.com Fixes: 15f4eae70d36 ("x86: Move thread_info into task_struct") Signed-off-by: Xi Kangjie Acked-by: Jan Kiszka Acked-by: Kieran Bingham Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/tasks.py | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts') diff --git a/scripts/gdb/linux/tasks.py b/scripts/gdb/linux/tasks.py index 1bf949c43b76..f6ab3ccf698f 100644 --- a/scripts/gdb/linux/tasks.py +++ b/scripts/gdb/linux/tasks.py @@ -96,6 +96,8 @@ def get_thread_info(task): thread_info_addr = task.address + ia64_task_size thread_info = thread_info_addr.cast(thread_info_ptr_type) else: + if task.type.fields()[0].type == thread_info_type.get_type(): + return task['thread_info'] thread_info = task['stack'].cast(thread_info_ptr_type) return thread_info.dereference() -- cgit