Re: [Nbd] [PATCH 2/2] nbd: Disallow ioctls on disconnected block device

Pranay Srivastava
2016-07-16T13:31:52Z

On Sat, Jul 16, 2016 at 4:56 PM, Wouter Verhelst <w@uter.be> wrote:
> On Sat, Jul 16, 2016 at 03:38:40PM +0530, Pranay Srivastava wrote:
>> Okay. So how about we include some negotiated key which goes in with every
>> request which the server could maintain for clients that can be checked while
>> resetting the connection with the same server?
>
> Wut?
>
>> So am I correct that this situation can
>> indeed happen or the server will throw an error back to client in case
>> the troubled
>> nbd-client is trying to reconnect to the original server but requests
>> are going to
>> another server?
>>
>> If yes to above query then what is the best effort we can do to avoid
>> such scenarios?
>
> Tell userspace not to do stupid things?
>
> This isn't a problem. The kernel assumes that whatever userspace does,
> once the connection is set up again everything's the way it was before.
> If that's not true, then userspace is to blame, not kernel space.
>
> Adding a "key" which we need to pass is going to make things wildly more
> complicated for no benefit.
Okay.
So let things roll for timeout but stop for disconnect.
>
> --
> < ron> I mean, the main *practical* problem with C++, is there's like a dozen
> people in the world who think they really understand all of its rules,
> and pretty much all of them are just lying to themselves too.
> -- #debian-devel, OFTC, 2016-02-12

--
---P.K.S