netdev - Re: [External] Re: [PATCH 0/7] Introduce vdpa management tool

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 1 Dec 2020 14:25:05 +0800
From:   Jason Wang <jasowang@...hat.com>
To:     Yongji Xie <xieyongji@...edance.com>
Cc:     Parav Pandit <parav@...dia.com>,
        virtualization@...ts.linux-foundation.org,
        "Michael S. Tsirkin" <mst@...hat.com>, elic@...dia.com,
        netdev@...r.kernel.org
Subject: Re: [External] Re: [PATCH 0/7] Introduce vdpa management tool


On 2020/11/30 下午3:07, Yongji Xie wrote:
>>> Thanks for adding me, Jason!
>>>
>>> Now I'm working on a v2 patchset for VDUSE (vDPA Device in Userspace)
>>> [1]. This tool is very useful for the vduse device. So I'm considering
>>> integrating this into my v2 patchset. But there is one problem：
>>>
>>> In this tool, vdpa device config action and enable action are combined
>>> into one netlink msg: VDPA_CMD_DEV_NEW. But in vduse case, it needs to
>>> be splitted because a chardev should be created and opened by a
>>> userspace process before we enable the vdpa device (call
>>> vdpa_register_device()).
>>>
>>> So I'd like to know whether it's possible (or have some plans) to add
>>> two new netlink msgs something like: VDPA_CMD_DEV_ENABLE and
>>> VDPA_CMD_DEV_DISABLE to make the config path more flexible.
>>>
>> Actually, we've discussed such intermediate step in some early
>> discussion. It looks to me VDUSE could be one of the users of this.
>>
>> Or I wonder whether we can switch to use anonymous inode(fd) for VDUSE
>> then fetching it via an VDUSE_GET_DEVICE_FD ioctl?
>>
> Yes, we can. Actually the current implementation in VDUSE is like
> this.  But seems like this is still a intermediate step. The fd should
> be binded to a name or something else which need to be configured
> before.


The name could be specified via the netlink. It looks to me the real 
issue is that until the device is connected with a userspace, it can't 
be used. So we also need to fail the enabling if it doesn't opened.

Thanks


>
> Thanks,
> Yongji
>