[Intel-gfx] [PATCH stable v5.2] drm/i915/vbt: Fix VBT parsing for the PSR section

Tue Jul 30 18:24:44 UTC 2019

> -----Original Message-----
> From: Greg KH [mailto:gregkh at linuxfoundation.org]
> Sent: Tuesday, July 30, 2019 10:09 AM
> To: Vivi, Rodrigo <rodrigo.vivi at intel.com>
> Cc: Nikula, Jani <jani.nikula at intel.com>; Joonas Lahtinen
> <joonas.lahtinen at linux.intel.com>; Souza, Jose <jose.souza at intel.com>;
> sashal at kernel.org; intel-gfx at lists.freedesktop.org; stable at vger.kernel.org;
> Pandiyan, Dhinakaran <dhinakaran.pandiyan at intel.com>
> Subject: Re: [Intel-gfx] [PATCH stable v5.2] drm/i915/vbt: Fix VBT parsing for
> the PSR section
> 
> On Tue, Jul 30, 2019 at 09:56:59AM -0700, Rodrigo Vivi wrote:
> >
> > On Tue, Jul 30, 2019 at 06:27:09PM +0200, Greg KH wrote:
> > > On Tue, Jul 30, 2019 at 09:22:07AM -0700, Rodrigo Vivi wrote:
> > > > On Tue, Jul 30, 2019 at 05:27:24PM +0200, Greg KH wrote:
> > > > > On Tue, Jul 30, 2019 at 08:19:08AM -0700, Rodrigo Vivi wrote:
> > > > > > Hi Greg,
> > > > > >
> > > > > > On Wed, Jul 24, 2019 at 10:40:29AM -0700, Rodrigo Vivi wrote:
> > > > > > > On Wed, Jul 24, 2019 at 05:27:42PM +0000, Souza, Jose wrote:
> > > > > > > > On Wed, 2019-07-24 at 14:06 +0200, Greg KH wrote:
> > > > > > > > > On Mon, Jul 22, 2019 at 04:13:25PM -0700, Dhinakaran Pandiyan
> wrote:
> > > > > > > > > > A single 32-bit PSR2 training pattern field follows the sixteen
> > > > > > > > > > element
> > > > > > > > > > array of PSR table entries in the VBT spec. But, we incorrectly
> > > > > > > > > > define
> > > > > > > > > > this PSR2 field for each of the PSR table entries. As a result,
> the
> > > > > > > > > > PSR1
> > > > > > > > > > training pattern duration for any panel_type != 0 will be
> parsed
> > > > > > > > > > incorrectly. Secondly, PSR2 training pattern durations for VBTs
> > > > > > > > > > with bdb
> > > > > > > > > > version >= 226 will also be wrong.
> > > > > > > > > >
> > > > > > > > > > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > > > > > > > > Cc: José Roberto de Souza <jose.souza at intel.com>
> > > > > > > > > > Cc: stable at vger.kernel.org
> > > > > > > > > > Cc: stable at vger.kernel.org #v5.2
> > > > > > > > > > Fixes: 88a0d9606aff ("drm/i915/vbt: Parse and use the new field
> > > > > > > > > > with PSR2 TP2/3 wakeup time")
> > > > > > > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111088
> > > > > > > > > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204183
> > > > > > > > > > Signed-off-by: Dhinakaran Pandiyan
> <dhinakaran.pandiyan at intel.com>
> > > > > > > > > > Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > > > > > > > > Reviewed-by: José Roberto de Souza <jose.souza at intel.com>
> > > > > > > > > > Acked-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > > > > > > > > Tested-by: François Guerraz <kubrick at fgv6.net>
> > > > > > > > > > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > > > > > > > > Link:
> > > > > > > > > >
> https://patchwork.freedesktop.org/patch/msgid/20190717223451.2595-1-
> dhinakaran.pandiyan at intel.com
> > > > > > > > > > (cherry picked from commit
> > > > > > > > > > b5ea9c9337007d6e700280c8a60b4e10d070fb53)
> > > > > > > > >
> > > > > > > > > There is no such commit in Linus's kernel tree :(
> > > > > > >
> > > > > > > not yet... It is queued for 5.3 on drm-intel-next-queued.
> > > > > > >
> > > > > > > This line is automatically added by "dim" tool when
> > > > > > > cherry-picking queued stuff for our drm-intel fixes branches.
> > > > > >
> > > > > > What do you need her from us to accept this patch?
> > > > >
> > > > > Um, you have read the stable kernel rules, right?
> > > > >     https://www.kernel.org/doc/html/latest/process/stable-kernel-
> rules.html
> > > > >
> > > > > That's what I need for it to go into a stable kernel release.
> > > >
> > > > Yes, I have read it. Maybe what I don't understand is just the fact that we
> will
> > > > let customers facing issues for 6 weeks or more while the original patch
> > > > doesn't land on Linus tree. :(
> > >
> > > Then get the patch into Linus's tree!
> > > Nothing I can do until that happens, you know this...
> >
> > -ENOTENOUGHCOFFEE sorry.
> > For some reason I thought this thread had started as the reject of your
> scripts.
> 
> That is correct.  But more coffee is always good.
> 
> > This patch is already queued on our drm-intel-fixes and will probably land on
> > Linus tree next week. Than your scripts will just get it.
> >
> > So, back to your original concern:
> >
> > The referrence b5ea9c9337007d6e700280c8a60b4e10d070fb53 you pointed out won't
> > exist until 5.3 merge window though.
> 
> That's fine.
> 
> > My question now is regarding our fixes flow adding these future references.
> > Do you have any concern with that?
> 
> I hate and despise and complain endlessly about how you all are doing
> this, but I have learned to just suck it up and accept it.  It is a
> major pain in the rear, and I will say that it causes me to delay all
> merges of stable drm patches that get merged in Linus's tree in -rc1
> until -rc2 or -rc3 is out usually as I have to go through and
> hand-determine if a reject happens because it really is a reject, or
> because this patch is already in the tree.
> 
> So, if this hits Linus's tree "like normal", my scripts will pick it up
> and all is good.  I can handle this crazy notation you all feel that
> works for you, but I reserve the right to complain.
> 
> This original patch, however, was sent only to stable and it seemed to
> indicate that I needed to pick it up because it already was upstream (I
> saw the cherry-pick line.)  As that is not the case here, fine, no harm,
> no foul, let's go get more coffee...

Not sure if it was my fault to have included the cherry-pick line, I'll talk
to Rodrigo offline to understand if that was the source of confusion.

-DK

> 
> greg k-h