The encoded data is just for debugging at kernel side and has
remained in normal code path until now, oops.

Change-Id: I3581bf73a6e6c9ec4b6228a670b6d8338f13ee14
Reviewed-on: https://go-review.googlesource.com/31535
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>