[RFC PATCH v4 00/37] objtool: add base support for arm64

From: Chen Zhongjin
Date: Fri Apr 29 2022 - 05:46:49 EST


This series enables objtool to start doing stack validation/check
on arm64 kernel builds.

Gathering Julien's previous work[1][2], now objtool can check build
on arm64 build for defconfig and yesconfig, with only few unreachable
warning.

This series includes objtool part (1-15) and arm64 part (16-37), if
necessary it can be taken apart as two series.

I'm not sure that UNWIND_HINT added to entry (33-36) is complete
and correct, because after Julien finished it there was a
refactoring for entry. It will be fully tested after I implement
unwinder_orc for arm64.

[1] https://lkml.org/lkml/2021/3/3/1135
[2] https://github.com/julien-thierry/linux.git

---
Changes v3 -> v4:
- [1] fix EX_ENTRY_SIZE from 8 to 12.
- [14-37] modify arm64 for supporting objtool, including annotation,
asm code modification, ignoring some validation, to make objtool
be enable to pass arm64 builds.

Changes v2 -> v3:
- [04] rebase Julien's version to mainstream and solve conflicts.
- [05, 06, 08] Merge dumplicate "*type = INSN_OTHER".
- [08, 09, 10] When meeting unrecognized instructions such as datas
in .text code or 0x0 padding insns, last version used
"loc->ignorable" to mark and remove them from objtool insn list.

However there are two problems to do so:
1. when meeting insns can't be decoded or excluded, objtool will
just stop.

2. deleting every insn can cause problems in fellow procedure.

So I changed "record_invalid_insn" that we can delete one insn or
just set it ignored. Now check will throw an error and going on when
meeting undecodable instructions.

Also, to prevent the confusion between "loc->ignorable" and
"insn->ignore" I changed "ignore" to "delete".

Changes v1 -> v2:
- Drop gcc plugin in favor of -fno-jump-tables
- miscelaneous fixes and cleanups

--->
Chen Zhongjin (6):
arm64: Add annotate_reachable() for objtools
arm64: irq-gic: Replace unreachable() with -EINVAL
arm64: ftrace: Skip validation of entry-ftrace.o
arm64: bpf: Skip validation of ___bpf_prog_run
arm64: Annotate ASM symbols with unknown stack state
arm64: entry: Align stack size for alternative

Julien Thierry (29):
tools: Add some generic functions and headers
tools: arm64: Make aarch64 instruction decoder available to tools
tools: bug: Remove duplicate definition
objtool: arm64: Add base definition for arm64 backend
objtool: arm64: Decode add/sub instructions
objtool: arm64: Decode jump and call related instructions
objtool: arm64: Decode other system instructions
objtool: arm64: Decode load/store instructions
objtool: arm64: Decode LDR instructions
objtool: arm64: Accept non-instruction data in code sections
objtool: arm64: Handle supported relocations in alternatives
objtool: arm64: Ignore replacement section for alternative callback
objtool: check: Support data in text section
objtool: arm64: Add unwind_hint support
arm64: bug: Add reachable annotation to warning macros
arm64: kgdb: Mark code following kgdb brk as reachable
arm64: Set intra-function call annotations
arm64: kernel: Skip validation of proton-pack.c.c and hibernate.c
arm64: kernel: Skip validation of sigreturn32.o
arm64: crypto: Remove unnecessary stackframe
arm64: sleep: Properly set frame pointer before call
arm64: Change symbol annotations
arm64: efi-header: Mark efi header as data
arm64: head: Mark constants as data
arm64: proc: Mark constant as data
arm64: crypto: Mark data in code sections
arm64: entry: Annotate valid stack in kernel entry
arm64: entry: Annotate code switching to tasks
arm64: kvm: Annotate stack state for guest enter/exit code

Raphael Gault (2):
objtool: arm64: Enable stack validation for arm64
arm64: kernel: Skip validation of kuser32.o

arch/arm64/Kconfig | 1 +
arch/arm64/Makefile | 4 +
arch/arm64/crypto/aes-neonbs-core.S | 14 +-
arch/arm64/crypto/crct10dif-ce-core.S | 5 +
arch/arm64/crypto/poly1305-armv8.pl | 4 +
arch/arm64/crypto/sha512-armv8.pl | 29 +-
arch/arm64/include/asm/assembler.h | 2 +
arch/arm64/include/asm/bug.h | 6 +-
arch/arm64/include/asm/kgdb.h | 1 +
arch/arm64/include/asm/unwind_hints.h | 27 +
arch/arm64/kernel/Makefile | 10 +
arch/arm64/kernel/cpu-reset.S | 2 +
arch/arm64/kernel/efi-entry.S | 2 +
arch/arm64/kernel/efi-header.S | 2 +
arch/arm64/kernel/entry.S | 29 +-
arch/arm64/kernel/head.S | 75 +-
arch/arm64/kernel/hibernate-asm.S | 2 +
arch/arm64/kernel/hibernate.c | 2 +
arch/arm64/kernel/proton-pack.c | 2 +
arch/arm64/kernel/relocate_kernel.S | 2 +
arch/arm64/kernel/sleep.S | 8 +-
arch/arm64/kvm/hyp/entry.S | 7 +-
arch/arm64/kvm/hyp/hyp-entry.S | 3 +
arch/arm64/kvm/hyp/vgic-v3-sr.c | 7 +-
arch/arm64/mm/proc.S | 4 +-
drivers/irqchip/irq-gic-v3.c | 2 +-
include/linux/compiler.h | 9 +
kernel/bpf/core.c | 3 +
tools/arch/arm64/include/asm/insn.h | 565 +++++++
tools/arch/arm64/include/asm/unwind_hints.h | 27 +
tools/arch/arm64/lib/insn.c | 1464 +++++++++++++++++
tools/include/asm-generic/bitops/__ffs.h | 11 +
tools/include/linux/bug.h | 6 +-
tools/include/linux/kernel.h | 21 +
tools/include/linux/printk.h | 40 +
tools/objtool/Makefile | 5 +
tools/objtool/arch/arm64/Build | 8 +
tools/objtool/arch/arm64/decode.c | 506 ++++++
.../arch/arm64/include/arch/cfi_regs.h | 14 +
tools/objtool/arch/arm64/include/arch/elf.h | 8 +
.../arch/arm64/include/arch/endianness.h | 9 +
.../objtool/arch/arm64/include/arch/special.h | 22 +
tools/objtool/arch/arm64/special.c | 36 +
tools/objtool/arch/x86/decode.c | 5 +
tools/objtool/check.c | 25 +-
tools/objtool/elf.c | 14 +
tools/objtool/include/objtool/arch.h | 3 +
tools/objtool/include/objtool/elf.h | 1 +
tools/objtool/sync-check.sh | 5 +
49 files changed, 2985 insertions(+), 74 deletions(-)
create mode 100644 arch/arm64/include/asm/unwind_hints.h
create mode 100644 tools/arch/arm64/include/asm/insn.h
create mode 100644 tools/arch/arm64/include/asm/unwind_hints.h
create mode 100644 tools/arch/arm64/lib/insn.c
create mode 100644 tools/include/linux/printk.h
create mode 100644 tools/objtool/arch/arm64/Build
create mode 100644 tools/objtool/arch/arm64/decode.c
create mode 100644 tools/objtool/arch/arm64/include/arch/cfi_regs.h
create mode 100644 tools/objtool/arch/arm64/include/arch/elf.h
create mode 100644 tools/objtool/arch/arm64/include/arch/endianness.h
create mode 100644 tools/objtool/arch/arm64/include/arch/special.h
create mode 100644 tools/objtool/arch/arm64/special.c

--
2.17.1