Re: [Nbd] found bug in nbd-server.c, handle_info()

[Alex Bligh <alex@...872...>]

> On 12 May 2017, at 09:20, Wouter Verhelst <w@...112...> wrote:
> 
> Hi Greg,
> 
> On Thu, May 11, 2017 at 09:53:54AM -0400, Menke, Gregory D. (GSFC-582.0)[Arctic Slope Technical Services, Inc.] wrote:
>> Thanks Wouter,
>> 
>> I'm chasing another issue seen both on the trunk and 3.15.2 where an 
>> apparent deadlock occurs, leaving the nbd device jammed until the 
>> filesystem op, client and server are SIGKILLed at which point the mount 
>> can be cleaned up.  In this case the tcp connection is running thru an 
>> ssh tunnel over a wan,
> 
> In that case, you're stacking TCP over TCP, which does not work very
> well. See http://sites.inka.de/~W1011/devel/tcp-tcp.html for a pretty
> good (technical) explanation on why that is the case.

I don't think that's write. nbd over an ssh tunnel over tcp only
has one tcp layer (the one transporting ssh).

-- 
Alex Bligh