[PATCH 4.9 044/108] drm/nouveau/fence/g84-: protect against concurrent access to semaphore buffers

Greg Kroah-Hartman
2017-06-15T17:58:23Z

From: Ben Skeggs <bskeggs@redhat.com>

[ Upstream commit 96692b097ba76d0c637ae8af47b29c73da33c9d0 ]

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/nouveau/nouveau_fence.h | 1 +
drivers/gpu/drm/nouveau/nv84_fence.c | 6 ++++++
2 files changed, 7 insertions(+)

--- a/drivers/gpu/drm/nouveau/nouveau_fence.h
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.h
@@ -100,6 +100,7 @@ struct nv84_fence_priv {
struct nouveau_bo *bo;
struct nouveau_bo *bo_gart;
u32 *suspend;
+ struct mutex mutex;
};

u64 nv84_fence_crtc(struct nouveau_channel *, int);
--- a/drivers/gpu/drm/nouveau/nv84_fence.c
+++ b/drivers/gpu/drm/nouveau/nv84_fence.c
@@ -121,8 +121,10 @@ nv84_fence_context_del(struct nouveau_ch
}

nouveau_bo_wr32(priv->bo, chan->chid * 16 / 4, fctx->base.sequence);
+ mutex_lock(&priv->mutex);
nouveau_bo_vma_del(priv->bo, &fctx->vma_gart);
nouveau_bo_vma_del(priv->bo, &fctx->vma);
+ mutex_unlock(&priv->mutex);
nouveau_fence_context_del(&fctx->base);
chan->fence = NULL;
nouveau_fence_context_free(&fctx->base);
@@ -148,11 +150,13 @@ nv84_fence_context_new(struct nouveau_ch
fctx->base.sync32 = nv84_fence_sync32;
fctx->base.sequence = nv84_fence_read(chan);

+ mutex_lock(&priv->mutex);
ret = nouveau_bo_vma_add(priv->bo, cli->vm, &fctx->vma);
if (ret == 0) {
ret = nouveau_bo_vma_add(priv->bo_gart, cli->vm,
&fctx->vma_gart);
}
+ mutex_unlock(&priv->mutex);

/* map display semaphore buffers into channel's vm */
for (i = 0; !ret && i < chan->drm->dev->mode_config.num_crtc; i++) {
@@ -232,6 +236,8 @@ nv84_fence_create(struct nouveau_drm *dr
priv->base.context_base = fence_context_alloc(priv->base.contexts);
priv->base.uevent = true;

+ mutex_init(&priv->mutex);
+
/* Use VRAM if there is any ; otherwise fallback to system memory */
domain = drm->device.info.ram_size != 0 ? TTM_PL_FLAG_VRAM :
/*