[Mesa-dev] [PATCH] i965: Fail to blit rather than assert on invalid pitch requirements.
kenneth at whitecape.org
Wed Dec 26 09:29:43 PST 2012
On 12/26/2012 08:32 AM, Paul Berry wrote:
> On 25 December 2012 20:55, Kenneth Graunke <kenneth at whitecape.org
> <mailto:kenneth at whitecape.org>> wrote:
> Dungeon Defenders hits TexImage()'s try_pbo_upload() path where
> image->Width == 2, which doesn't meet intelEmitCopyBlit's requirement
> that the pitch needs to be a multiple of 4.
> Since intelEmitCopyBlit can already fail for a myriad of other reasons,
> and it's not clear that other callers are immune to this failure mode,
> simply make it return false rather than assert.
> Fixes Dungeon Defenders on i965/Ivybridge. Now playable (aside from
> having to work around the EXT_bindable_uniform issue).
> NOTE: This is probably a candidate for the 9.0 branch.
> src/mesa/drivers/dri/intel/intel_blit.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
> diff --git a/src/mesa/drivers/dri/intel/intel_blit.c
> index 521e6eb..867d7b3 100644
> --- a/src/mesa/drivers/dri/intel/intel_blit.c
> +++ b/src/mesa/drivers/dri/intel/intel_blit.c
> @@ -150,8 +150,8 @@ intelEmitCopyBlit(struct intel_context *intel,
> /* Blit pitch must be dword-aligned. Otherwise, the hardware
> appears to drop
> * the low bits.
> - assert(src_pitch % 4 == 0);
> - assert(dst_pitch % 4 == 0);
> + if (src_pitch % 4 != 0 || dst_pitch % 4 != 0)
> + return false;
> /* For big formats (such as floating point), do the copy using
> 32bpp and
> * multiply the coordinates.
> Looks reasonable to me.
> Reviewed-by: Paul Berry <stereotype441 at gmail.com
> <mailto:stereotype441 at gmail.com>>
> As a follow-up, we should probably check all of the code paths that lead
> into this function to make sure they invoke the proper fallback logic if
> there is a return value of false. I think that _mesa_ReadnPixelsARB,
> for example, will just fail to copy any data.
They don't, which is bothersome...I'm not sure they check the
preconditions nor the return value.
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