Any objections/comments on axing out old ATA stack?

[Ian Smith]

On Sat, 30 Mar 2013 21:00:24 -0700, Peter Wemm wrote:
 > On Sat, Mar 30, 2013 at 4:29 PM, Matthias Andree <mandree at freebsd.org> wrote:
 > > Am 27.03.2013 22:22, schrieb Alexander Motin:
 > >> Hi.
 > >>
 > >> Since FreeBSD 9.0 we are successfully running on the new CAM-based ATA
 > >> stack, using only some controller drivers of old ata(4) by having
 > >> `options ATA_CAM` enabled in all kernels by default. I have a wish to
 > >> drop non-ATA_CAM ata(4) code, unused since that time from the head
 > >> branch to allow further ATA code cleanup.
 > >>
 > >> Does any one here still uses legacy ATA stack (kernel explicitly built
 > >> without `options ATA_CAM`) for some reason, for example as workaround
 > >> for some regression? Does anybody have good ideas why we should not drop
 > >> it now?
 > >
 > > Alexander,
 > >
 > > The regression in http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/157397
 > > where the SATA NCQ slots stall for some Samsung drives in the new stack,
 > > and consequently hang the computer for prolonged episodes where it is in
 > > the NCQ error handling, disallows removal of the old driver. (Last
 > > checked with 9.1-RELEASE at current patchlevel.)
 > 
 > We're talking about 10.x, so if you want it fixed, you need update
 > with 10.x information.
 > 
 > Please put 10.x diagnostics in the PR.

Given Alexander also posted this to -stable, just for clarity, are we 
_only_ talking about 10.x here, or might this change get MFC'd to 9?

cheers, Ian

(dropping -current as I'm not subscribed so would only get bounced)