Re: [Xen-devel] [PATCH V4 3/4] Introduce XEN scsiback module

[Juergen Gross <jgross@suse.com>]

On 08/14/2014 10:53 AM, Juergen Gross wrote:
> Nicholas,
>
> just one more question (see below):
>
> On 08/12/2014 11:13 PM, Nicholas A. Bellinger wrote:
>> Hi Juergen & Co,
>>
>> Finally had a chance to review this code.  Comments are inline below..
>>
>> On Fri, 2014-08-08 at 09:49 +0200, jgross@suse.com wrote:
>
> ...
>
>>> +    if (IS_ERR(tv_nexus->tvn_se_sess)) {
>>> +        mutex_unlock(&tpg->tv_tpg_mutex);
>>> +        kfree(tv_nexus);
>>> +        return -ENOMEM;
>>> +    }
>>> +    se_sess = tv_nexus->tvn_se_sess;
>>> +    /*
>>> +     * Since we are running in 'demo mode' this call with generate a
>>> +     * struct se_node_acl for the scsiback struct se_portal_group with
>>> +     * the SCSI Initiator port name of the passed configfs group
>>> 'name'.
>>> +     */
>>> +    tv_nexus->tvn_se_sess->se_node_acl =
>>> core_tpg_check_initiator_node_acl(
>>> +                se_tpg, (unsigned char *)name);
>>> +    if (!tv_nexus->tvn_se_sess->se_node_acl) {
>>> +        mutex_unlock(&tpg->tv_tpg_mutex);
>>> +        pr_debug("core_tpg_check_initiator_node_acl() failed for %s\n",
>>> +             name);
>>> +        goto out;
>>> +    }
>
> Can I drop the call to core_tpg_check_initiator_node_acl() as well?
> Keeping it will result in failing to setup the nexus (which is to be
> expected IMHO).

Obviously I can't. transport_lookup_cmd_lun() calls right at start
spin_lock_irqsave(&se_sess->se_node_acl->device_list_lock, flags);
resulting in a page fault...

I guess the hint to just throw away all the node_acl related stuff has
to be adjusted somehow...

So: what is needed, what can be removed?


Juergen