[PATCH v4a 00/38] timers: Use timer_shutdown*() before freeing timers

[Linus Torvalds]

On Sat, Nov 5, 2022 at 2:03 PM Jason A. Donenfeld <Jason at zx2c4.com> wrote:
>
> Something that might help here is changing the `...` into
> `... when exists` or into `... when != ptr` or similar.

I actually tried that.

You don't want "when exists", you'd want "when forall", but that seems
to be the default.

And trying "when != ptr->timer" actually does the right thing in that
it gets rid of the case where the timer is modified outside of the
del_timer() case, *but* it also causes odd other changes to the
output.

Look at what it generates for that

   drivers/media/usb/pvrusb2/pvrusb2-hdw.c

file, which finds a lot of triggers with the "when !=  ptr->timer",
but only does one without it.

So I gave up, just because I clearly don't understand the rules.

(Comparing output is also fun because the ordering of the patches is
random, so consecutive runs with the same rule will give different
patches. I assume that it's just because it's done in parallel, but it
doesn't help the "try to see what changes when you change the script"
;)

                 Linus