On Thu, Jan 21, 2021 at 09:44:17AM -0800, Linus Torvalds wrote:

On Thu, Jan 21, 2021 at 1:40 AM Jiri Slaby [off-list ref] wrote:

quoted

Ok, here belongs my earlier note: "if ld == NULL => crash here." That is
if hangup happens during the ldisc wait, the kernel will crash in
tty_ldisc_deref.

Right you are, good catch.

quoted

Is there a reason not to convert hung_up_tty_fops too and leave the
return hung_up_tty_write here intact? This would also solve the comments
above.

No, no reason. I started out just changing that one tty_write, then
noticed that I had to change the redirect case too, but never then got
to "yeah, I should have changed the hup case as well".

Greg, do you prefer a new series, or incremental patches?

Incremental patches please as these are already in my public branches
and I would have to revert them and add new ones but that's messy, so
fixes on top is fine.

thanks,

greg k-h