From: José Roberto de Souza jose.souza@intel.com
[ Upstream commit 6c10ba06bb1b48acce6d4d9c1e33beb9954f1788 ]
By default xe_bb_create_job() appends a MI_BATCH_BUFFER_END to batch buffer, this is not a problem if batch buffer is only used once but oa reuses the batch buffer for the same metric and at each call it appends a MI_BATCH_BUFFER_END, printing the warning below and then overflowing.
[ 381.072016] ------------[ cut here ]------------ [ 381.072019] xe 0000:00:02.0: [drm] Assertion `bb->len * 4 + bb_prefetch(q->gt) <= size` failed! platform: LUNARLAKE subplatform: 1 graphics: Xe2_LPG / Xe2_HPG 20.04 step B0 media: Xe2_LPM / Xe2_HPM 20.00 step B0 tile: 0 VRAM 0 B GT: 0 type 1
So here checking if batch buffer already have MI_BATCH_BUFFER_END if not append it.
v2: - simply fix, suggestion from Ashutosh
Cc: Ashutosh Dixit ashutosh.dixit@intel.com Signed-off-by: José Roberto de Souza jose.souza@intel.com Reviewed-by: Ashutosh Dixit ashutosh.dixit@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20240912153842.35813-1-jose.so... (cherry picked from commit 9ba0e0f30ca42a98af3689460063edfb6315718a) Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/xe/xe_bb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xe/xe_bb.c b/drivers/gpu/drm/xe/xe_bb.c index 541361caff3b0..5cae7ecfc431e 100644 --- a/drivers/gpu/drm/xe/xe_bb.c +++ b/drivers/gpu/drm/xe/xe_bb.c @@ -65,7 +65,8 @@ __xe_bb_create_job(struct xe_exec_queue *q, struct xe_bb *bb, u64 *addr) { u32 size = drm_suballoc_size(bb->bo);
- bb->cs[bb->len++] = MI_BATCH_BUFFER_END; + if (bb->len == 0 || bb->cs[bb->len - 1] != MI_BATCH_BUFFER_END) + bb->cs[bb->len++] = MI_BATCH_BUFFER_END;
xe_gt_assert(q->gt, bb->len * 4 + bb_prefetch(q->gt) <= size);