Re: [PATCH] drm/i915/bdw: Fix 4g GGTT insert entries regression

[Ben Widawsky <ben@bwidawsk.net>]

On Wed, Mar 05, 2014 at 07:24:37AM -0800, Ben Widawsky wrote:
> On Wed, Mar 05, 2014 at 11:13:12AM +0200, Jani Nikula wrote:
> > On Wed, 05 Mar 2014, Ben Widawsky <benjamin.widawsky@intel.com> wrote:
> > > The PDE needs to wrap after writing all the PTEs. Quite a small/silly
> > > bug to find in the massive change. It was introduced:
> > > commit 307dc4f99f6d3a74a78b0e776838f35b2004f14d
> > > Author: Ben Widawsky <benjamin.widawsky@intel.com>
> > > Date:   Thu Feb 20 11:51:21 2014 -0800
> > >
> > >     drm/i915/bdw: Reorganize PT allocations
> > 
> > As noted in the bug, the commit merged to dinq is correct, and the
> > commit referenced above apparently only lives in some temporary branch.
> > 
> > BR,
> > Jani.
> > 
> 
> My eyes are playing tricks on me. Sorry for the noise.
> 

It's not my eyes. It's something else. WTF is going on?

bwidawsk@bolo_yeung ~/intel-gfx/drm-intel (drm-intel-nightly)$ tsocks git fetch upstream 
bwidawsk@bolo_yeung ~/intel-gfx/drm-intel (drm-intel-nightly)$ git reset --hard upstream/drm-intel-nightly 
HEAD is now at 97d10a0 drm-intel-nightly: 2014y-03m-05d-20h-31m-21s integration manifest
bwidawsk@bolo_yeung ~/intel-gfx/drm-intel (drm-intel-nightly)$ sed -n '338p' drivers/gpu/drm/i915/i915_gem_gtt.c
			if (pde + 1 == GEN8_PDES_PER_PAGE) {

> > 
> > >
> > > I can't actually test this patch at the moment because my Broadwell is
> > > unresponsive. This should be squashed if possible.
> > >
> > > Cc: Imre Deak <imre.deak@intel.com>
> > > Reported-by: Timo Aaltonen <tjaalton@ubuntu.com>
> > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75763
> > > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> > > ---
> > >  drivers/gpu/drm/i915/i915_gem_gtt.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > index 5462037..2bde703 100644
> > > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > > @@ -335,7 +335,7 @@ static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
> > >  		if (++pte == GEN8_PTES_PER_PAGE) {
> > >  			kunmap_atomic(pt_vaddr);
> > >  			pt_vaddr = NULL;
> > > -			if (pde + 1 == GEN8_PDES_PER_PAGE) {
> > > +			if (++pde == GEN8_PDES_PER_PAGE) {
> > >  				pdpe++;
> > >  				pde = 0;
> > >  			}
> > > -- 
> > > 1.9.0
> > >
> > > _______________________________________________
> > > Intel-gfx mailing list
> > > Intel-gfx@lists.freedesktop.org
> > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > 
> > -- 
> > Jani Nikula, Intel Open Source Technology Center
> 
> -- 
> Ben Widawsky, Intel Open Source Technology Center

-- 
Ben Widawsky, Intel Open Source Technology Center