Re: bcache-3.2 branch

[Kent Overstreet <koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>]

On Wed, Jun 20, 2012 at 10:08:51PM +1000, Joseph Glanville wrote:
> Hi Kent and list,
> 
> I have pulled down the latest bcache code and have been playing around
> with it when I noticed that I am having issues starting Xen virtual
> machines using bcache + LVM.
> What is interesting is the QEMU storage emulation in userspace is able
> to access the device fine however blkback kernel module which uses the
> device directly seems to fail.
> How would I go about debugging any of this?
> 
> Older versions of bcache work fine so it's a regression as far as I can tell.

Hey, sorry for the delay - I just got back from my first sort-of
vacation in... awhile :P

I'm pretty sure I know the approximate source of the regression - I
fairly recently reworked some code in the generic block layer to handle
arbitrary size bios (which enabled some major cleanups in the bcache
code). I've chased down a few bugs with that code since then.

Got some logs for me to look at? Or did you want me to give you pointers
on debugging kernel code? :)

> 
> Joseph.
> 
> -- 
> CTO | Orion Virtualisation Solutions | www.orionvm.com.au
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