Re: [PATCH] dm transaction manager: handle space map checker failure

[Vivek Goyal <vgoyal@redhat.com>]

On Wed, Jun 20, 2012 at 05:20:10PM -0400, Vivek Goyal wrote:
> On Wed, Jun 20, 2012 at 03:24:59PM -0400, Mike Snitzer wrote:
> > If CONFIG_DM_DEBUG_SPACE_MAPS is enabled and dm_sm_checker_create()
> > fails, dm_tm_create_internal() would still return success even though it
> > cleaned up all resources it was supposed to have created.
> > 
> > Fix the space map checker code to return an appropriate ERR_PTR and have
> > dm_tm_create_internal() check for it with IS_ERR.
> > 
> 
> I tested the patch and it works. It fails gracefully instead of segfaulting.
> 
> device-mapper: reload ioctl failed: Cannot allocate memory
> 
> I still do get waring though about large memory allocation. That's a
> separate issue though.

I put a trace_printk() in ca_create() to see how much memory we are trying
to allocated using kzalloc. And answer is 10485760. Number of blocks
obtained from space map is 2621440. I think this might be happening because 
my metadata device size is 10G.

Thanks
Vivek