| Message ID | 20161219124346.550-2-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Dec 19, 2016 at 12:43:46PM +0000, Chris Wilson wrote: > In commit 0c40ce130e38 ("drm/i915: Trim the object sg table"), we expect > to copy exactly orig_st->nents across and allocate the table thusly. > The copy loop should therefore end with the new_sg being NULL. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> > --- > drivers/gpu/drm/i915/i915_gem.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > index 4e263df2afc3..0a82cce5f731 100644 > --- a/drivers/gpu/drm/i915/i915_gem.c > +++ b/drivers/gpu/drm/i915/i915_gem.c > @@ -2316,6 +2316,7 @@ static void i915_sg_trim(struct sg_table *orig_st) > /* called before being DMA mapped, no need to copy sg->dma_* */ > new_sg = sg_next(new_sg); > } > + GEM_BUG_ON(new_sg); /* Should walk exactly nents and hit the end */ I wasn't sure this holds up vs. overallocation of sg tables, but the last entry is marked and that mark seems to survive intact everywhere. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > > sg_free_table(orig_st); > > -- > 2.11.0 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On 19/12/2016 12:43, Chris Wilson wrote: > In commit 0c40ce130e38 ("drm/i915: Trim the object sg table"), we expect > to copy exactly orig_st->nents across and allocate the table thusly. > The copy loop should therefore end with the new_sg being NULL. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> > --- > drivers/gpu/drm/i915/i915_gem.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > index 4e263df2afc3..0a82cce5f731 100644 > --- a/drivers/gpu/drm/i915/i915_gem.c > +++ b/drivers/gpu/drm/i915/i915_gem.c > @@ -2316,6 +2316,7 @@ static void i915_sg_trim(struct sg_table *orig_st) > /* called before being DMA mapped, no need to copy sg->dma_* */ > new_sg = sg_next(new_sg); > } > + GEM_BUG_ON(new_sg); /* Should walk exactly nents and hit the end */ > > sg_free_table(orig_st); > I was sure I had this in the code back then, hm. Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Regards, Tvrtko
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 4e263df2afc3..0a82cce5f731 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2316,6 +2316,7 @@ static void i915_sg_trim(struct sg_table *orig_st) /* called before being DMA mapped, no need to copy sg->dma_* */ new_sg = sg_next(new_sg); } + GEM_BUG_ON(new_sg); /* Should walk exactly nents and hit the end */ sg_free_table(orig_st);
In commit 0c40ce130e38 ("drm/i915: Trim the object sg table"), we expect to copy exactly orig_st->nents across and allocate the table thusly. The copy loop should therefore end with the new_sg being NULL. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> --- drivers/gpu/drm/i915/i915_gem.c | 1 + 1 file changed, 1 insertion(+)