Re: [PATCH v3 09/10] objtool: Make unwind hints definitions available to other architectures

From: Josh Poimboeuf
Date: Fri Sep 04 2020 - 14:49:14 EST


On Fri, Sep 04, 2020 at 04:30:27PM +0100, Julien Thierry wrote:
> +/*
> + * UNWIND_HINT_TYPE_CALL: Indicates that sp_reg+sp_offset resolves to PREV_SP
> + * (the caller's SP right before it made the call). Used for all callable
> + * functions, i.e. all C code and all callable asm functions.
> + *
> + * UNWIND_HINT_TYPE_REGS: Used in entry code to indicate that sp_reg+sp_offset
> + * points to a fully populated pt_regs from a syscall, interrupt, or exception.
> + *
> + * UNWIND_HINT_TYPE_REGS_IRET: Used in entry code to indicate that sp_reg+sp_offset
> + * points to the iret return frame.

Now that this is generic, I think REGS_PARTIAL would be better.

> + *
> + * The UNWIND_HINT macros are used only for the unwind_hint struct. They
> + * aren't used in struct orc_entry due to size and complexity constraints.
> + * Objtool converts them to real types when it converts the hints to orc
> + * entries.

Now that ORC_TYPE_* have been replaced by UNWIND_HINT_TYPE_*, I think
this last paragraph should be removed.

--
Josh