Re: [PATCH] drm/ttm: Print the memory decryption status just once

[Christian König]

Sorry haven't seen your reply. Feel free to add my rb to the patch.

Regards,
Christian.

Am 18.04.24 um 13:38 schrieb Zack Rusin:
> Ping on this one. If we don't want the "_once" then I can quickly
> prepare a patch that just removes the logging altogether, because
> while useful it's polluting up the kernel logs too much right now so
> getting a fix in for 6.9 for this would be great.
>
> z
>
> On Mon, Apr 8, 2024 at 1:46 PM Zack Rusin <zack.rusin@xxxxxxxxxxxx> wrote:
> > Sorry, apologies to everyone. By accident I replied off the list.
> > Redoing it now on the list. More below.
> >
> > On Mon, Apr 8, 2024 at 12:10 PM Christian König
> > <christian.koenig@xxxxxxx> wrote:
> > > Am 08.04.24 um 18:04 schrieb Zack Rusin:
> > > > On Mon, Apr 8, 2024 at 11:59 AM Christian König
> > > > <christian.koenig@xxxxxxx> wrote:
> > > > > Am 08.04.24 um 17:56 schrieb Zack Rusin:
> > > > > > Stop printing the TT memory decryption status info each time tt is created
> > > > > > and instead print it just once.
> > > > > >
> > > > > > Reduces the spam in the system logs when running guests with SEV enabled.
> > > > > Do we then really need this in the first place?
> > > > Thomas asked for it just to have an indication when those paths are
> > > > being used because they could potentially break things pretty bad. I
> > > > think it is useful knowing that those paths are hit (but only once).
> > > > It makes it pretty easy for me to tell whether bug reports with people
> > > > who report black screen can be answered with "the kernel needs to be
> > > > upgraded" ;)
> > > Sounds reasonable, but my expectation was rather that we would print
> > > something on the device level.
> > >
> > > If that's not feasible for whatever reason than printing it once works
> > > as well of course.
> > TBH, I think it's pretty convenient to have the drm_info in the TT
> > just to make sure that when drivers request use_dma_alloc on SEV
> > systems TT turns decryption on correctly, i.e. it's a nice sanity
> > check when reading the logs. But if you'd prefer it in the driver I
> > can move this logic there as well.
> >
> > z