On Fri, 25 Mar 2022 11:09:40 +0100 Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Fri, Mar 25, 2022 at 01:29:01PM +0900, Masami Hiramatsu wrote: > > Replaces the kretprobe code with rethook on x86. With this patch, > > kretprobe on x86 uses the rethook instead of kretprobe specific > > trampoline code. > > > > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> > > --- > > arch/x86/Kconfig | 1 > > arch/x86/include/asm/unwind.h | 23 +++---- > > arch/x86/kernel/Makefile | 1 > > arch/x86/kernel/kprobes/common.h | 1 > > arch/x86/kernel/kprobes/core.c | 107 ---------------------------------- > > arch/x86/kernel/rethook.c | 121 ++++++++++++++++++++++++++++++++++++++ > > 6 files changed, 135 insertions(+), 119 deletions(-) > > create mode 100644 arch/x86/kernel/rethook.c > > I'm thinking you'll find it builds much better with this on... Oops, Thanks. I've tested it with framepointer based unwinder... > > diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c > index 2de3c8c5eba9..794fdef2501a 100644 > --- a/arch/x86/kernel/unwind_orc.c > +++ b/arch/x86/kernel/unwind_orc.c > @@ -550,15 +550,15 @@ bool unwind_next_frame(struct unwind_state *state) > } > /* > * There is a small chance to interrupt at the entry of > - * __kretprobe_trampoline() where the ORC info doesn't exist. > - * That point is right after the RET to __kretprobe_trampoline() > + * arch_rethook_trampoline() where the ORC info doesn't exist. > + * That point is right after the RET to arch_rethook_trampoline() > * which was modified return address. > - * At that point, the @addr_p of the unwind_recover_kretprobe() > + * At that point, the @addr_p of the unwind_recover_rethook() > * (this has to point the address of the stack entry storing > * the modified return address) must be "SP - (a stack entry)" > * because SP is incremented by the RET. > */ > - state->ip = unwind_recover_kretprobe(state, state->ip, > + state->ip = unwind_recover_rethook(state, state->ip, > (unsigned long *)(state->sp - sizeof(long))); > state->regs = (struct pt_regs *)sp; > state->prev_regs = NULL; > @@ -573,7 +573,7 @@ bool unwind_next_frame(struct unwind_state *state) > goto err; > } > /* See UNWIND_HINT_TYPE_REGS case comment. */ > - state->ip = unwind_recover_kretprobe(state, state->ip, > + state->ip = unwind_recover_rethook(state, state->ip, > (unsigned long *)(state->sp - sizeof(long))); > > if (state->full_regs) -- Masami Hiramatsu <mhiramat@xxxxxxxxxx>
