How to disable all GEOM tasting?

[Rotate 13]

On Tue, 30 Jul 2013 16:41:14 -0500, Brooks Davis <brooks at freebsd.org> wrote:

> On Mon, Jul 29, 2013 at 05:14:04PM +0000, Rotate 13 wrote:
>> How to disable *all* GEOM tasting of newly-attached devices?  I looked
>> through the manuals, searched web, grepped sysctl -ad.  I only find
>> sysctl to disable all tasting for graid (kern.geom.raid.enable).
>>
>> Example, if I have removable drive I want to pop in and access from
>> userland with open("/dev/foo0", O_RDONLY); without various GEOM
>> modules first trying to understand.
>
> As far as I know there is no way to do this, but the existence of
> partition tables shouldn't have any effect on your ability to open the raw
> device as long as you haven't configured something in devd or similar to
> open those partitions.
>
> -- Brooks

Thanks for reply.

Any pointer to look in sources for where triggers the tasting?  I
understand each GEOM has the taste code of its own...  but something
must start it all when device is inserted.

I am comfortable reading/writing C code but definitely not kernel
hacker.  Much easier with small hint in right direction!