Re: [GIT PULL] 9p update for 5.7

[Linus Torvalds]

On Mon, Apr 6, 2020 at 4:07 AM Dominique Martinet
<asmadeus@xxxxxxxxxxxxx> wrote:
>
> - Fix read with O_NONBLOCK to allow incomplete read and return
> immediately

Hmm. This is kind of special semantics (normally a POSIX filesystem
ignores O_NONBLOCK), but I guess it makes sense for a network
filesystem.

It might be worth a bti more documentation/commenting because of the
special semantics. For example, since you don't have 'poll()',
O_NONBLOCK doesn't really mean "nonblocking", it means "stop earlier"
if I read that patch right. You can't just return -EAGAIN because
there's no way to then avoid busy looping..

                Linus