drm/omap: EBUSY status handling in omap_gem_fault()

Subsequent threads returning EBUSY from vm_insert_pfn() was not
handled correctly. As a result concurrent access from new threads
to mmapped data caused SIGBUS.

See e79e0fe380847493266fba557217e2773c61bd1b ("drm/i915: EBUSY status
handling added to i915_gem_fault()").

Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index baa714c..9ac3056 100644 (file)
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -578,6 +578,11 @@ fail:
        case 0:
        case -ERESTARTSYS:
        case -EINTR:
+       case -EBUSY:
+               /*
+                * EBUSY is ok: this just means that another thread
+                * already did the job.
+                */
                return VM_FAULT_NOPAGE;
        case -ENOMEM:
                return VM_FAULT_OOM;