Re: [PATCH] random: opportunistically initialize on /dev/urandom reads

[Linus Torvalds]

On Tue, Apr 5, 2022 at 11:31 AM Jason A. Donenfeld <Jason@xxxxxxxxx> wrote:
>
> It sounds like your suggestion would be to make that:
>
>   while (!crng_ready()) {
>     int ret;
>
>     try_to_generate_entropy();
>     if (nodelay && !crng_ready()) {
>       warn(...);
>       return -EBUSY;
>     }
>     ret = wait_event_interruptible_timeout(crng_init_wait, crng_ready(), HZ);
>     if (ret)
>       return ret > 0 ? 0 : ret;
>   }

Yes. Except I'd almost warn for the "ret < 0" case too, since almost
nobody seems to check it.

But hey, maybe callers that are interrupted by a signal check for that
separately. I guess it's _possible_.

             Linus