Re: [PATCH 0/2] drm/nouveau: avoid usage of list iterator after loop

From: Lyude Paul
Date: Tue Mar 07 2023 - 17:49:40 EST


Actually hm, dim is warning me about this and making me realize there's
probably a better way to handle this, going to revoke the previous r-b I gave
and respond inline

On Tue, 2023-03-07 at 17:43 -0500, Lyude Paul wrote:
> Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
>
> Will push upstream in just a moment
>
> On Wed, 2023-03-01 at 18:25 +0100, Jakob Koschel wrote:
> > This patch set includes two instances where the list iterator variable
> > 'pstate' is implicitly assumed to be valid after the iterator loop.
> > While in pratice that is most likely the case (if
> > 'pstatei'/'args->v0.state' is <= the elements in clk->states), we should
> > explicitly only allow 'pstate' to always point to correct 'nvkm_pstate'
> > structs.
> >
> > That allows catching potential bugs with BUG_ON(!pstate) that otherwise
> > would be completely undetectable.
> >
> > It also helps the greater mission to hopefully move the list iterator
> > variable into the iterating macro directly [1].
> >
> > Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@xxxxxxxxxxxxxx/ [1]
> > Signed-off-by: Jakob Koschel <jkl820.git@xxxxxxxxx>
> > ---
> > Jakob Koschel (2):
> > drm/nouveau/device: avoid usage of list iterator after loop
> > drm/nouveau/clk: avoid usage of list iterator after loop
> >
> > drivers/gpu/drm/nouveau/nvkm/engine/device/ctrl.c | 9 ++++++---
> > drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c | 9 ++++++---
> > 2 files changed, 12 insertions(+), 6 deletions(-)
> > ---
> > base-commit: c0927a7a5391f7d8e593e5e50ead7505a23cadf9
> > change-id: 20230301-drm-nouveau-avoid-iter-after-loop-4bff97166efa
> >
> > Best regards,
>

--
Cheers,
Lyude Paul (she/her)
Software Engineer at Red Hat