Re: [PATCH 2/2] x86/entry: Fix unwinding from kprobe on PUSH/POP instruction

[Peter Zijlstra]

On Mon, Feb 13, 2023 at 11:43:57PM +0900, Masami Hiramatsu wrote:

> > Fix it by annotating the #BP exception as a non-signal stack frame,
> > which tells the ORC unwinder to decrement the instruction pointer before
> > looking up the corresponding ORC entry.
> 
> Just to make it clear, this sounds like a 'hack' use of non-signal stack
> frame. If so, can we change the flag name as 'literal' or 'non-literal' etc?
> I concern that the 'signal' flag is used differently in the future.

Oooh, bike-shed :-) Let me suggest trap=1, where a trap is a fault with
a different return address, specifically the instruction after the
faulting instruction.