HEADSUP new usb code coming in.

[M. Warner Losh]

In message: <48B0EA50.2090105 at mawer.org>
            Antony Mawer <fbsd-current at mawer.org> writes:
: On 23/08/2008 8:08 PM, Volker wrote:
: > On 12/23/-58 20:59, Antony Mawer wrote:
: >> M. Warner Losh wrote:
: >>> In message: <48AB566B.5010507 at mawer.org>
: >>>             Antony Mawer <fbsd-current at mawer.org> writes:
: >>> : Warner Losh wrote:
: >>> : > From: Bakul Shah <bakul at bitblocks.com>
: >>> : > Subject: Re: HEADSUP new usb code coming in. : > Date: Tue, 19 Aug
: >>> 2008 14:18:13 -0700
: >>> : > : >> On Tue, 19 Aug 2008 22:44:20 +0200 Hans Petter Selasky
: >>> <hselasky at c2i.net>  wrote:
: >>> : >>> New stuff (all of which I can remember right now):
: >>> : >>     ...
: >>> : >>
: >>> : >> Accidentally unplugging a mounted USB disk (without
: >>> : >> unmounting it) resulted in a hang or a crash.  Is this fixed?
: >>> : > : > That's fixed in -current right now with the old stack.  It
: >>> isn't a usb
: >>> : > issue at all, but a buffer cache issue.
: >>> : : Is this change that is likely to be MFC'd in time for 7.1? And/or
: >>> is : there a specific patch that can manually be applied to -STABLE to
: >>> fix this?
: >>>
: >>> I should spend the time to dig into the changes in current.  There
: >>> turned out to be several little changes...  And I need to verify all
: >>> the edge cases were covered...
: >> I'd be happy to test patches if you do end up doing this.. it would be
: >> really nice to have in 7.1, or at least available as a patchset if it
: >> isn't suitable for MFC (eg. ABI changes)...
: > 
: > I'm a bit behind with reading emails. Please forgive me if this has
: > already been answered.
: > 
: > Don't expect the new USB stack for 7.1-R. It's too short and the new USB
: > stack will introduce an ABI breakage. For that, all drivers written for
: > the old USB stack need to be rewritten and I guess, we need to take care
: > about 3rd party developers and inform them in advance about that massive
: > change. I would not wonder if this will never get MFC'd but I don't know
: > actually.
: 
: This wasn't about the new USB stack -- we were discussing the buffer 
: cache and CAM-related fixes that prevents the system from panic'ing when 
: a USB device is unplugged without first unmounting the filesystem. These 
: patches are in HEAD with the existing USB stack. :-)

The best I can do is say "Maybe" and the answer is closer to yes if
somebody data-mines the changes I've made in this area in -current.
That's the hard part of back porting them..

Warner