svn commit: r316767 - head/sys/amd64/amd64

[Alexey Dokuchaev]

On Sat, Jun 10, 2017 at 11:51:25PM +0000, Alexey Dokuchaev wrote:
> On Thu, Apr 13, 2017 at 03:49:55PM +0000, Konstantin Belousov wrote:
> > New Revision: 316767
> > URL: https://svnweb.freebsd.org/changeset/base/316767
> > 
> > Log:
> >   Map DMAP as nx.
> >   
> >   Demotions preserve PG_NX, so it is enough to set nx bit for initial
> >   lowest-level paging entries.
> 
> Hi Kostik,
> 
> It seems this change breaks resume with radeonkms(4): my laptop fells into
> sleep, but upon resume it immediately reboots with kernels after r316767.
> 
> Reverting these two lines fixes resuming at least up to r316986, but the
> latest -CURRENT still reboots, perhaps for another reason.

Second revision is r318318 which looks related to r316767.  Updating kernel
to the latest revision and backing out these two (any one of them alone is
not enough) fixed resume for me.

Apparently something else is required for nx-mapped DMAP.  Anything I can
help with debugging this?

./danfe