From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@suse.com>
Subject: Re: RFC: removing hardcoded "modprobe blktap" in
	xencommons
Date: Mon, 15 Jul 2013 15:13:19 +0100
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	<51E40240.5010108@eu.citrix.com>
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To: Wei Liu <wei.liu2@citrix.com>, George Dunlap <george.dunlap@eu.citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>, xen-devel@lists.xen.org
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>>> On 15.07.13 at 16:08, George Dunlap <george.dunlap@eu.citrix.com> wrote:
> On 15/07/13 10:38, Wei Liu wrote:
>> On Mon, Jul 15, 2013 at 10:34:02AM +0100, Jan Beulich wrote:
>>>>>> On 15.07.13 at 10:26, Wei Liu <wei.liu2@citrix.com> wrote:
>>>> So my point is, if every driver follows the kernel convention
>>>> (open(/dev/XYZ) would cause the module to load automatically) there then
>>>> would be minimal changes to libxl. It is unmaintained kernel modules
>>>> like blktap makes it not feasible to make things simplier.
>>>>
>>>> (Wild guess below, correct me if I'm wrong)
>>>>
>>>> Say, if we could make it just like open(blkback_char_dev), the loading
>>>> is just a one-liner and doesn't need to be using libxl's AO interface.
>>> Once again - most if not all backends don't fit that model - blktap
>>> as said doesn't and neither blkback nor netback don't as they don't
>>> create any /dev nodes.
>>>
>> OK, I get what you mean.
>>
>>> Backend module loading might be triggerable through xenstore
>>> node watches...
>>>
>> Sure.
> 
> If we did something like this, we'd still have to have the modprobes in 
> xencommons for older kernels; we'd just have to have a way to disable it 
> for newer kernels.

Oh, I was actually thinking of user space (tool stack) watches. But
then again I'm not really sure this idea would work out at all...

Jan