Date: Thu, 19 Dec 2002 18:26:12 +0100 From: Bernd Walter <ticso@cicely8.cicely.de> To: Matthew Dillon <dillon@apollo.backplane.com> Cc: Bernd Walter <ticso@cicely8.cicely.de>, Frode Nordahl <frode@nordahl.net>, freebsd-current@FreeBSD.ORG Subject: Re: UMASS USB bug? (getting the Sony disk-on-key device working). Message-ID: <20021219172612.GI29286@cicely8.cicely.de> In-Reply-To: <200212191706.gBJH6Jfk041140@apollo.backplane.com> References: <200212191032.gBJAWNj0039522@apollo.backplane.com> <1040296107.2012.23.camel@ws24.ns5.powertech.no> <20021219153805.GG29286@cicely8.cicely.de> <200212191706.gBJH6Jfk041140@apollo.backplane.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Dec 19, 2002 at 09:06:19AM -0800, Matthew Dillon wrote:
>
> :
> :On Thu, Dec 19, 2002 at 12:08:27PM +0100, Frode Nordahl wrote:
> :> Hey, Matt
> :>
> :> While you're at it, could you have a look at PR kern/46176 ? =)
> :>
> :> At least would you tell me if you have the same problem with your
> :> device(s)
> :
> :The umass cam interaction is questionable.
> :I've seen lots of problems caused by this.
> :As I have problems with my device caused by this too I already placed it on
> :my todo list.
>
> The panic described in 46176 has happened to me on -current. On
> -stable I have managed (very easily) to get the CAM layer vs UMASS
> layer into a confused state where the CAM layer thinks it is still
> attached but the UMASS layer thinks it has detached / cleaned everything
> out. In both cases it appears that memory is being freed by one side
> which is still being used by the other side but I haven't tracked down
> the exact cause.
The umass driver uses a single sim for all umass devices.
There are a lot of workarounds and bugs introduced because of this.
Also there is a small static limit (IIRC 3) in the number of instances
supported.
You could see a difference in behavour, if you have another umass
device connected.
I wouldn't be surprised if this problem belongs here too.
My guess would be because umass disconnects the sim on the last
instance but tells cam to rescan the pseudo bus.
My intention is to rewrite the parts of umass to use multiple sims
so LUNs and many instances actually work and hopefully a lot of other
problems like this can be solved too.
BTW: I've seen such disconnect/reconnect problems with -stable too,
but without a panic.
--
B.Walter COSMO-Project http://www.cosmo-project.de
ticso@cicely.de Usergroup info@cosmo-project.de
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20021219172612.GI29286>