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
7cf7b4323116fe1fc7e40add523998646cfe934e ("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>
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;