From: José Roberto de Souza Date: Thu, 12 Sep 2024 15:38:42 +0000 (-0700) Subject: drm/xe/oa: Fix overflow in oa batch buffer X-Git-Tag: v6.13-rc1~122^2~20^2~82 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9ba0e0f30ca42a98af3689460063edfb6315718a;p=thirdparty%2Fkernel%2Flinux.git drm/xe/oa: Fix overflow in oa batch buffer 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 Signed-off-by: José Roberto de Souza Reviewed-by: Ashutosh Dixit Link: https://patchwork.freedesktop.org/patch/msgid/20240912153842.35813-1-jose.souza@intel.com --- diff --git a/drivers/gpu/drm/xe/xe_bb.c b/drivers/gpu/drm/xe/xe_bb.c index a13e0b3a169ed..ef777dbdf4ecc 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);