Re: [PATCH] uart: fix race between uart_put_char() and uart_shutdown()

From: Tycho Andersen
Date: Wed Jun 06 2018 - 17:42:18 EST


On Mon, Jun 04, 2018 at 10:59:36PM -0500, Serge E. Hallyn wrote:
> Quoting Tycho Andersen (tycho@xxxxxxxx):
> > Unfortunately, I don't have any insightful thoughts about how to test this.
> > Ideas are appreciated :)
>
> I wonder whether there is something we can do with qemu -serial pipe: ?

Good idea. I couldn't get tty_put_char() to trigger nicely, but I just
hard coded one to occur, so at least now I know that this doesn't
deadlock when called normally.

Another suggestion Serge gave off list was to write a kernel module
that implemented a driver. I'll see about doing that to see if I can
force the original crash.

> > Signed-off-by: Tycho Andersen <tycho@xxxxxxxx>
>
> Acked-by: Serge Hallyn <serge@xxxxxxxxxx>

Thanks!

Tycho