Re: [PATCH 08/11] objtool/loongarch: Add unwind hints in prepare_frametrace()

[Tiezhu Yang]

On 04/01/2025 03:08 PM, Ingo Molnar wrote:
> * Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
>
> > If 'regs' points to a local stack variable, prepare_frametrace() stores
> > all registers to the stack.  This confuses objtool as it expects them to
> > be restored from the stack later.
> >
> > The stores don't affect stack tracing, so use unwind hints to hide them
> > from objtool.
> >
> > Fixes the following warnings:
> >
> >   arch/loongarch/kernel/traps.o: warning: objtool: show_stack+0xe0: stack state mismatch: reg1[22]=-1+0 reg2[22]=-2-160
> >   arch/loongarch/kernel/traps.o: warning: objtool: show_stack+0xe0: stack state mismatch: reg1[23]=-1+0 reg2[23]=-2-152
> >
> > Cc: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> > Fixes: cb8a2ef0848c ("LoongArch: Add ORC stack unwinder support")
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > Closes: https://lore.kernel.org/oe-kbuild-all/202503280703.OARM8SrY-lkp@xxxxxxxxx/
> > Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
>
> Note, I skipped this fix from tip:objtool/urgent for the time being,
> because Tiezhu Yang indicated that he'd be reviewing and testing this
> patch.

Tested-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>