On Sat, Jan 05, 2019 at 01:54:03PM -0800, Linus Torvalds wrote:

On Sat, Jan 5, 2019 at 12:43 PM Jiri Kosina [off-list ref] wrote:

quoted

quoted

Who actually _uses_ mincore()? That's probably the best guide to what
we should do. Maybe they open the file read-only even if they are the
owner, and we really should look at file ownership instead.

Yeah, well

        https://codesearch.debian.net/search?q=mincore

is a bit too much mess to get some idea quickly I am afraid.

Anyway, the Debian code search just results in mostly non-present
stuff. It's sad that google code search is no more. It was great for
exactly these kinds of questions.

If you select the "Group search results by Debian source package"
option on the search results page it makes it a lot easier to skim
through.

It looks to me like Firefox is expecting mincore() not to fail on
libraries that it has mapped:

https://sources.debian.org/src/firefox-esr/60.4.0esr-1/mozglue/linker/BaseElf.cpp/?hl=98#L98

    - Kevin

The mono runtime seems to have some mono_pages_not_faulted() function,
but I don't know if people use it for file mappings, and I couldn't
find any interesting users of it.

I didn't find anything that seems to really care, but I gave up after
a few pages of really boring stuff.

                    Linus