diff options
| author | Francisco Jerez <currojerez@riseup.net> | 2010-10-18 03:53:39 +0200 |
|---|---|---|
| committer | Ben Skeggs <bskeggs@redhat.com> | 2010-12-03 15:06:35 +1000 |
| commit | 3945e47543863385b54d94c94b023ee7ca9df972 (patch) | |
| tree | 209eb523c0e3a01069f8e18751b97373804a22d3 /drivers/gpu/drm/nouveau/nv20_graph.c | |
| parent | fcccab2e4eb8d579837481054cc2cb28eea0baef (diff) | |
drm/nouveau: Refactor context destruction to avoid a lock ordering issue.
The destroy_context() engine hooks call gpuobj management functions to
release the channel resources, these functions use HARDIRQ-unsafe locks
whereas destroy_context() is called with the HARDIRQ-safe
context_switch_lock held, that's a lock ordering violation.
Push the engine-specific channel destruction logic into destroy_context()
and let the hardware-specific code lock and unlock when it's actually
needed. Change the engine destruction order to avoid a race in the small
gap between pgraph and pfifo context uninitialization.
Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/nouveau/nv20_graph.c')
| -rw-r--r-- | drivers/gpu/drm/nouveau/nv20_graph.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/gpu/drm/nouveau/nv20_graph.c b/drivers/gpu/drm/nouveau/nv20_graph.c index 12ab9cd56ec..8a040201255 100644 --- a/drivers/gpu/drm/nouveau/nv20_graph.c +++ b/drivers/gpu/drm/nouveau/nv20_graph.c @@ -425,9 +425,21 @@ nv20_graph_destroy_context(struct nouveau_channel *chan) struct drm_device *dev = chan->dev; struct drm_nouveau_private *dev_priv = dev->dev_private; struct nouveau_pgraph_engine *pgraph = &dev_priv->engine.graph; + unsigned long flags; - nouveau_gpuobj_ref(NULL, &chan->ramin_grctx); + spin_lock_irqsave(&dev_priv->context_switch_lock, flags); + pgraph->fifo_access(dev, false); + + /* Unload the context if it's the currently active one */ + if (pgraph->channel(dev) == chan) + pgraph->unload_context(dev); + + pgraph->fifo_access(dev, true); + spin_unlock_irqrestore(&dev_priv->context_switch_lock, flags); + + /* Free the context resources */ nv_wo32(pgraph->ctx_table, chan->id * 4, 0); + nouveau_gpuobj_ref(NULL, &chan->ramin_grctx); } int |