Re: [PATCH v6 3/6] fs/procfs: add build ID fetching to PROCMAP_QUERY API

[Andi Kleen]

> So what exactly did you have in mind when you were proposing that
> check? Did you mean to do a pass over all VMAs within the process to
> check if there is at least one executable VMA belonging to
> address_space? If yes, then that would certainly be way too expensive
> to be usable.

I was thinking to only report the build ID when the VMA queried
is executable. If software wanted to look up a data symbol
and needs that buildid it would need to check a x vma too.

Normally tools iterate over all the mappings anyways so this
shouldn't be a big burden for them.

Did I miss something?

I guess an alternative would be a new VMA flag, but iirc we're low on
bits there already.

-Andi