OpenCloudOS-Kernel/tools/arch
Josh Poimboeuf fb799447ae x86,objtool: Split UNWIND_HINT_EMPTY in two
Mark reported that the ORC unwinder incorrectly marks an unwind as
reliable when the unwind terminates prematurely in the dark corners of
return_to_handler() due to lack of information about the next frame.

The problem is UNWIND_HINT_EMPTY is used in two different situations:

  1) The end of the kernel stack unwind before hitting user entry, boot
     code, or fork entry

  2) A blind spot in ORC coverage where the unwinder has to bail due to
     lack of information about the next frame

The ORC unwinder has no way to tell the difference between the two.
When it encounters an undefined stack state with 'end=1', it blindly
marks the stack reliable, which can break the livepatch consistency
model.

Fix it by splitting UNWIND_HINT_EMPTY into UNWIND_HINT_UNDEFINED and
UNWIND_HINT_END_OF_STACK.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/fd6212c8b450d3564b855e1cb48404d6277b4d9f.1677683419.git.jpoimboe@kernel.org
2023-03-23 23:18:58 +01:00
..
alpha/include tools headers uapi: Sync asm-generic/mman-common.h and linux/mman.h 2019-03-28 14:31:56 -03:00
arc/include/uapi/asm tools arch uapi: Copy missing unistd.h headers for arc, hexagon and riscv 2019-05-02 16:00:20 -04:00
arm/include tools headers kvm: Sync kvm headers with the kernel sources 2019-12-02 12:54:13 -03:00
arm64/include tools headers arm64: Sync arm64's cputype.h with the kernel sources 2023-01-18 10:07:42 -03:00
csky/include/uapi/asm csky: Add support for libdw 2019-05-15 16:36:46 -03:00
hexagon/include/uapi/asm tools arch uapi: Copy missing unistd.h headers for arc, hexagon and riscv 2019-05-02 16:00:20 -04:00
ia64/include ia64: tools: remove duplicate definition of ia64_mf() on ia64 2021-04-16 16:10:37 -07:00
loongarch/include/uapi/asm tools: Add LoongArch build infrastructure 2023-02-25 22:12:18 +08:00
microblaze/include/uapi/asm License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
mips/include perf tools: Copy uapi/asm/perf_regs.h from the kernel for MIPS 2021-06-01 10:07:46 -03:00
parisc/include/uapi/asm parisc: Align parisc MADV_XXX constants with all other architectures 2022-12-17 23:19:39 +01:00
powerpc/include perf powerpc: Add support to expose instruction and data address registers as part of extended regs 2021-10-25 13:47:42 -03:00
riscv/include/uapi/asm Replace HTTP links with HTTPS ones: RISC-V 2020-07-30 11:37:40 -07:00
s390/include tools headers kvm s390: Sync headers with the kernel sources 2022-08-19 15:30:34 -03:00
sh/include sh: remove sh5 support 2020-06-01 14:48:52 -04:00
sparc/include tools headers UAPI: Update tools's copy of mman.h headers 2019-07-29 09:02:58 -03:00
x86 x86,objtool: Split UNWIND_HINT_EMPTY in two 2023-03-23 23:18:58 +01:00
xtensa/include tools headers uapi: Sync asm-generic/mman-common.h and linux/mman.h 2019-03-28 14:31:56 -03:00