From d9c148cfaf0a99296ad7c92fb8b65952196053ec Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Thu, 14 Nov 2019 10:03:43 +0200 Subject: [PATCH] drm/omap: fix dma_addr refcounting cec4fa7511ef7a73eb635834e9d85b25a5b47a98 ("drm/omap: use refcount API to track the number of users of dma_addr") changed omap_gem.c to use refcounting API to track dma_addr uses. However, the driver only tracks the refcounts for non-contiguous buffers, and the patch didn't fully take this in account. After the patch, the driver always decreased refcount in omap_gem_unpin, instead of decreasing the refcount only for non-contiguous buffers. This leads to refcounting mismatch. As for the contiguous cases the refcount is never increased, fix this issue by returning from omap_gem_unpin if the buffer being unpinned is contiguous. Signed-off-by: Tomi Valkeinen Link: https://patchwork.freedesktop.org/patch/msgid/20191114080343.30704-1-tomi.valkeinen@ti.com Fixes: cec4fa7511ef ("drm/omap: use refcount API to track the number of users of dma_addr") Reviewed-by: Laurent Pinchart --- drivers/gpu/drm/omapdrm/omap_gem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c index e518d93..d08ae95 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem.c +++ b/drivers/gpu/drm/omapdrm/omap_gem.c @@ -843,9 +843,13 @@ fail: */ static void omap_gem_unpin_locked(struct drm_gem_object *obj) { + struct omap_drm_private *priv = obj->dev->dev_private; struct omap_gem_object *omap_obj = to_omap_bo(obj); int ret; + if (omap_gem_is_contiguous(omap_obj) || !priv->has_dmm) + return; + if (refcount_dec_and_test(&omap_obj->dma_addr_cnt)) { ret = tiler_unpin(omap_obj->block); if (ret) { -- 2.7.4