[PATCH v2 00/20] objtool: vmlinux.o and CLANG LTO support

From: Josh Poimboeuf
Date: Thu Jan 21 2021 - 16:32:09 EST


v2:
- fix commit description for why xen hypervisor page contents don't
matter [Juergen]
- annotate indirect jumps as safe instead of converting them to
retpolines [Andrew, Juergen]
- drop patch 1 - fake jumps no longer exist
- add acks

Based on tip/objtool/core.


Add support for proper vmlinux.o validation, which will be needed for
Sami's upcoming x86 LTO set. (And vmlinux validation is the future for
objtool anyway, for other reasons.)

This isn't 100% done -- most notably, crypto still needs to be supported
-- but I think this gets us most of the way there.

This can also be found at

git://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git objtool-vmlinux

And for more testing it can be combined with Sami's x86 LTO patches:

https://github.com/samitolvanen/linux clang-lto


Josh Poimboeuf (20):
objtool: Fix error handling for STD/CLD warnings
objtool: Fix retpoline detection in asm code
objtool: Fix ".cold" section suffix check for newer versions of GCC
objtool: Support retpoline jump detection for vmlinux.o
x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub
objtool: Assume only ELF functions do sibling calls
objtool: Add asm version of STACK_FRAME_NON_STANDARD
objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC
objtool: Add xen_start_kernel() to noreturn list
objtool: Move unsuffixed symbol conversion to a helper function
objtool: Add CONFIG_CFI_CLANG support
x86/xen: Support objtool validation in xen-asm.S
x86/xen: Support objtool vmlinux.o validation in xen-head.S
x86/xen/pvh: Annotate indirect branch as safe
x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S
x86/acpi: Annotate indirect branch as safe
x86/acpi: Support objtool validation in wakeup_64.S
x86/power: Annotate indirect branches as safe
x86/power: Move restore_registers() to top of the file
x86/power: Support objtool validation in hibernate_asm_64.S

arch/x86/include/asm/unwind_hints.h | 13 +---
arch/x86/kernel/acpi/Makefile | 1 -
arch/x86/kernel/acpi/wakeup_64.S | 4 +
arch/x86/kernel/ftrace_64.S | 8 +-
arch/x86/lib/retpoline.S | 2 +-
arch/x86/platform/pvh/head.S | 2 +
arch/x86/power/Makefile | 1 -
arch/x86/power/hibernate_asm_64.S | 103 +++++++++++++-------------
arch/x86/xen/Makefile | 1 -
arch/x86/xen/xen-asm.S | 29 +++++---
arch/x86/xen/xen-head.S | 5 +-
include/linux/objtool.h | 13 +++-
tools/include/linux/objtool.h | 13 +++-
tools/objtool/arch/x86/decode.c | 4 +-
tools/objtool/arch/x86/special.c | 2 +-
tools/objtool/check.c | 89 ++++++++++++----------
tools/objtool/elf.c | 88 ++++++++++++++++------
tools/objtool/include/objtool/check.h | 12 ++-
tools/objtool/include/objtool/elf.h | 2 +-
19 files changed, 240 insertions(+), 152 deletions(-)

--
2.29.2