2941482ead
This doesn't actually happen now, but there's a test case for an earlier kernel where a GPU error is signalled on one of nv50's fake channels, and the ramht lookup by the IRQ handler triggered an oops. This adds a check for RAMHT's existance on a channel before looking up an object handle. Signed-off-by: Ben Skeggs <bskeggs@redhat.com>