Re: [PATCH] sockets: Use SOMAXCONN for Unix socket listen()

[Eric Blake <eblake@redhat.com>]

On 2/5/21 3:55 AM, Daniel P. Berrangé wrote:

>> +++ b/util/qemu-sockets.c
>> @@ -1059,7 +1059,7 @@ int unix_listen(const char *str, Error **errp)
>>
>>      saddr = g_new0(UnixSocketAddress, 1);
>>      saddr->path = g_strdup(str);
>> -    sock = unix_listen_saddr(saddr, 1, errp);
>> +    sock = unix_listen_saddr(saddr, SOMAXCONN, errp);
>>      qapi_free_UnixSocketAddress(saddr);
>>      return sock;
>>  }
> 
> This method is a legacy back compat function, only used by the QEMU
> guest agent, so this can't explain the NBD problems, which use the
> QIONetListener class.
> 
> IOW, the problem is in the qemu-nbd.c / blockdev-nbd.c code I believe

D'oh. Serves me right for trying to guess the spot using just a grep on
listen() rather than running under gdb with a breakpoint to find the
actual backtrace.  v2 posted with a slightly changed subject line, and
this time tested to actually work.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org