On Gen4+, brw_finish_batch() calls brw_emit_query_end(), which emits some extra PIPE_CONTROLs to capture the current occlusion query data. Unfortunately, it was being called *after* _intel_batchbuffer_flush added the MI_BATCH_BUFFER_END, meaning those PIPE_CONTROLs didn't get inside the batch.
Not only does this likely cause bogus occlusion query values, it can also cause crashes: with the recent change to use 64-bit depth count writes on Gen6+, we started emitting an odd-length PIPE_CONTROL, which happened after the MI_NOOP padding. This resulted in an odd-length batch buffer, which resulted in execbuf2 returning -EINVAL and the application dying with an intel_do_flush_locked failure. On older generations, finish_batch() doesn't emit any state, so this change shouldn't have any effect. Huge thanks to Chris Wilson for helping me figure this out. NOTE: This is a candidate for stable release branches. Cc: Chris Wilson <ch...@chris-wilson.co.uk> Cc: Eric Anholt <e...@anholt.net> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=53311 Signed-off-by: Kenneth Graunke <kenn...@whitecape.org> --- src/mesa/drivers/dri/intel/intel_batchbuffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/mesa/drivers/dri/intel/intel_batchbuffer.c b/src/mesa/drivers/dri/intel/intel_batchbuffer.c index ac133ee..06cbaec 100644 --- a/src/mesa/drivers/dri/intel/intel_batchbuffer.c +++ b/src/mesa/drivers/dri/intel/intel_batchbuffer.c @@ -230,6 +230,9 @@ _intel_batchbuffer_flush(struct intel_context *intel, intel->batch.reserved_space = 0; + if (intel->vtbl.finish_batch) + intel->vtbl.finish_batch(intel); + /* Mark the end of the buffer. */ intel_batchbuffer_emit_dword(intel, MI_BATCH_BUFFER_END); if (intel->batch.used & 1) { @@ -237,9 +240,6 @@ _intel_batchbuffer_flush(struct intel_context *intel, intel_batchbuffer_emit_dword(intel, MI_NOOP); } - if (intel->vtbl.finish_batch) - intel->vtbl.finish_batch(intel); - intel_upload_finish(intel); /* Check that we didn't just wrap our batchbuffer at a bad time. */ -- 1.7.10.4 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
