This is a note to let you know that I've just added the patch titled drm/vc4: Fix overflow mem unreferencing when the binner runs dry. to the 4.7-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-vc4-fix-overflow-mem-unreferencing-when-the-binner-runs-dry.patch and it can be found in the queue-4.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9326e6f25574bbb8bd48206d245654780e3fd665 Mon Sep 17 00:00:00 2001 From: Eric Anholt <eric@xxxxxxxxxx> Date: Tue, 26 Jul 2016 13:47:14 -0700 Subject: drm/vc4: Fix overflow mem unreferencing when the binner runs dry. From: Eric Anholt <eric@xxxxxxxxxx> commit 9326e6f25574bbb8bd48206d245654780e3fd665 upstream. Overflow memory handling is tricky: While it's still referenced by the BPO registers, we want to keep it from being freed. When we are putting a new set of overflow memory in the registers, we need to assign the old one to the last rendering job using it. We were looking at "what's currently running in the binner", but since the bin/render submission split, we may end up with the binner completing and having no new job while the renderer is still processing. So, if we don't find a bin job at all, look at the highest-seqno (last) render job to attach our overflow to. Signed-off-by: Eric Anholt <eric@xxxxxxxxxx> Fixes: ca26d28bbaa3 ("drm/vc4: improve throughput by pipelining binning and rendering jobs") Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/vc4/vc4_drv.h | 9 +++++++++ drivers/gpu/drm/vc4/vc4_irq.c | 4 +++- 2 files changed, 12 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -321,6 +321,15 @@ vc4_first_render_job(struct vc4_dev *vc4 struct vc4_exec_info, head); } +static inline struct vc4_exec_info * +vc4_last_render_job(struct vc4_dev *vc4) +{ + if (list_empty(&vc4->render_job_list)) + return NULL; + return list_last_entry(&vc4->render_job_list, + struct vc4_exec_info, head); +} + /** * struct vc4_texture_sample_info - saves the offsets into the UBO for texture * setup parameters. --- a/drivers/gpu/drm/vc4/vc4_irq.c +++ b/drivers/gpu/drm/vc4/vc4_irq.c @@ -83,8 +83,10 @@ vc4_overflow_mem_work(struct work_struct spin_lock_irqsave(&vc4->job_lock, irqflags); current_exec = vc4_first_bin_job(vc4); + if (!current_exec) + current_exec = vc4_last_render_job(vc4); if (current_exec) { - vc4->overflow_mem->seqno = vc4->finished_seqno + 1; + vc4->overflow_mem->seqno = current_exec->seqno; list_add_tail(&vc4->overflow_mem->unref_head, ¤t_exec->unref_list); vc4->overflow_mem = NULL; Patches currently in stable-queue which might be from eric@xxxxxxxxxx are queue-4.7/drm-vc4-fix-oops-when-userspace-hands-in-a-bad-bo.patch queue-4.7/drm-vc4-use-drm_free_large-on-handles-to-match-its-allocation.patch queue-4.7/drm-vc4-fix-overflow-mem-unreferencing-when-the-binner-runs-dry.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html