[PATCH v2 0/2] x86/retpoline,kprobes: Fix the [__indirect_thunk_start, ..end] range

From: Petr Pavlu
Date: Tue Jul 11 2023 - 05:25:15 EST


Fix problems with an output position of thunk sections and the
associated definition of range [__indirect_thunk_start,
__indirect_thunk_end] which affects the kprobes optimization.

Initial v1 of the series kept the mentioned range but it turns out the
logic which uses it is not necessary so it is removed altogether.

Changes since v1 [1]:
- Drop the patch which moved the return thunk out of
[__indirect_thunk_start, ..end] and instead replace it with a removal
of the kprobes optimization check which looked for calls to indirect
thunks.
- Slightly adjust the commit message for the first patch, to better
match the new second patch.

[1] https://lore.kernel.org/lkml/20230705081547.25130-1-petr.pavlu@xxxxxxxx/

Petr Pavlu (2):
x86/retpoline,kprobes: Fix position of thunk sections with
CONFIG_LTO_CLANG
x86/retpoline,kprobes: Skip optprobe check for indirect jumps with
retpolines and IBT

arch/x86/include/asm/nospec-branch.h | 3 ---
arch/x86/kernel/kprobes/opt.c | 40 +++++++++++-----------------
arch/x86/kernel/vmlinux.lds.S | 4 +--
arch/x86/lib/retpoline.S | 4 +--
tools/perf/util/thread-stack.c | 4 +--
5 files changed, 20 insertions(+), 35 deletions(-)

--
2.35.3