RE: [PATCH v2 0/9] Add new command to print the shadow stack backtrace

Schimpe, Christina
2026-03-02T12:39:47Z

Just some update for the open for inferior calls, please see below.

[...]

> 3) For non-return addresses on the shadow stack, we want to display a string,
> as already implemented for signals. For inferior calls, we also want to display
> <function called by GDB>. The return address for inferior calls is pushed onto
> the shadow stack by GDB, but we currently don’t have a way to distinguish
> this address from normal return addresses. Thiago suggested pushing the
> return address together with a marker, but it’s still unclear how this marker
> should look like.

I investigated this a bit, and concluded that it should be possible to implement without
manipulating the shadow stack further (e.g. with marker element).

There are several options, and I'll probably go ahead and implement this by detecting
the inferior call breakpoint address in the shadow stack unwind logic.

Christina
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