Re: [Qemu-devel] [PATCH v3 0/3] nonblocking connect address handling cleanup

[Markus Armbruster]

Orit Wasserman <address@hidden> writes:

> On 09/20/2012 04:19 PM, Markus Armbruster wrote:
>> Orit Wasserman <address@hidden> writes:
>> 
>>> Changes from v2:
>>>     - remove the use of getnameinfo
>>>     - remove errp for inet_connect_addr
>>>     - remove QemuOpt "block"
>>>     - fix errors in wait_for_connect 
>>>     - pass ConnectState as a parameter to allow concurrent connect ops
>>>
>>> getaddrinfo can give us a list of addresses, but we only try to
>>> connect to the first one. If that fails we never proceed to
>>> the next one.  This is common on desktop setups that often have ipv6
>>> configured but not actually working.
>>> A simple way to reproduce the problem is migration:
>>> for the destination use -incoming tcp:0:4444, run migrate -d
>>> tcp:localhost:4444
>>> migration will fail on hosts that have both IPv4 and IPV6 address
>>> for localhost.
>>>
>>> To fix this, refactor address resolution code and make
>>> inet_nonblocking_connect
>>> retry connection with a different address.
>> 
>> Almost there for connect.
>> 
>> I'm afraid we have a similar problem with listen: we bind only on the
>> first address that works.  Shouldn't we bind all of them?
>> 
>> http://www.akkadia.org/drepper/userapi-ipv6.html
>> 
> yes listen should be fixed but lets do it in a separate patch set.

Absolutely.