On Tue, 2013-09-24 at 10:18 +0200, Christophe Leroy wrote:

Activating CONFIG_PIN_TLB is supposed to pin the IMMR and the first three
8Mbytes pages. But the setting of MD_CTR to a pinnable entry was missing before
the pinning of the third 8Mb page. As the index is decremented module 28
(MD_RSV4D is set) after every DTLB update, the third 8Mbytes page was
not pinned.

The examples you showed weren't quite modulo 28, more like "if (x >= 28)
x -= 4".  I'll fix up the changelog on applying, to read something like
"As the index is decremented to a value within the first 28 entries
(MD_RSV4D is set)...".

-Scott