Re: Unstableness in grant table block drivers

[Anthony Liguori <aliguori@us.ibm.com>]

Ian Pratt wrote:

>OK, that's news to us - we haven't seen any problems.
>
>It's been tested with dd's and kernel builds, and wasn't expected to be
>a particularly dangerous change.
>
>How you confirmed that disabling the option fixes your problems? Can you
>give a simple recipe to provoke problems?
>
We've had three different systems lose the ability to start domUs.  
Disabling VBD grant tables fixed the problem.  The best reproducable 
example we have is default config on a domU from today's xen-unstable 
snapshot.  /dev/console is not accessible and no valid root is found.

In my own case, it was working fairly well and then it just stopped 
working.  It would die mid-way through boot.  Again, disabling VBD 
grant-tables fixed the problem.  I'm going to look into the problem this 
evening and see if I can get you guys a more reproducable scenario.

>It doesn't seem to be destablizing, at least for us. Possibly there's
>been some feature interaction with later checkins. 
>  
>
Possibly.

>Anyone using the unstable tree should be reading the changelog
>closely...
>  
>
I agree.  I do, but I don't think a lot of people do.  I'm not trying to 
give you guys more work to do :-)  Just a quick note to xen-devel would 
suffice (if you've got an extra second).

Thanks Ian,

Regards,
Anthony Liguori

>Ian
>
>  
>