Am 05.03.2012 09:59, schrieb Amos Kong: > ----- Original Message ----- >> Am 02.03.2012 20:54, schrieb Laine Stump: >>> On 03/02/2012 05:35 AM, Kevin Wolf wrote: >>>> Am 02.03.2012 10:58, schrieb Amos Kong: >>>>> On 02/03/12 11:38, Amos Kong wrote: >>>>>>>> --- a/net.c >>>>>>>> +++ b/net.c >>>>>>>> @@ -84,7 +84,7 @@ static int get_str_sep(char *buf, int >>>>>>>> buf_size, >>>>>>>> const char **pp, int sep) >>>>>>>> const char *p, *p1; >>>>>>>> int len; >>>>>>>> p = *pp; >>>>>>>> - p1 = strchr(p, sep); >>>>>>>> + p1 = strrchr(p, sep); >>>>>>>> if (!p1) >>>>>>>> return -1; >>>>>>>> len = p1 - p; >>>>>>> And what if the port isn't specified? I think you would >>>>>>> erroneously >>>>>>> interpret the last part of the IP address as port. >>>>> Hi Kevin, port must be specified in '-incoming' parameters and >>>>> migrate >>>>> monitor cmd. >>>>> >>>>> qemu-kvm ... -incoming tcp:$host:$port >>>>> (qemu) migrate -d tcp:$host:$port >>>>> >>>>> >>>>> If use boot up guest by wrong cmdline, qemu will report an error >>>>> msg. >>>>> >>>>> # ./x86_64-softmmu/qemu-system-x86_64 --enable-kvm -boot n >>>>> -incoming >>>>> tcp:2312::8272 -monitor stdio >>>>> qemu-system-x86_64: qemu: getaddrinfo: Name or service not known >>>>> tcp_server_start: Invalid argument >>>>> Migration failed. Exit code tcp:2312::8272(-22), exiting. >>>> Which is because 2312: isn't a valid IP address, right? But what >>>> if you >>>> have something like 2312::1234:8272? If you misinterpret the 8272 >>>> as a >>>> port number, the remaining address is still a valid IPv6 address. >>> >>> This is made irrelevant by PATCH 4/4, which allows for the IP >>> address to >>> be placed inside brackets: >>> >>> [2312::8272]:port >>> >>> (at least it's irrelevant if your documentation *requires* brackets >>> for >>> all numeric ipv6-address:port pairs, which is strongly recommended >>> by >>> RFC 5952). It really is impossible to disambiguate the meaning of >>> the >>> final ":nnnn" unless you require these brackets (or 1) require full >>> specification of all potential colons in the IPv6 address or >>> require >>> that the port *always* be specified, neither of which seem >>> acceptable to >>> me). >> >> Here you're actually explaining why it's not irrelevant. You don't >> want >> to enforce port numbers, so 2312::1234:8272 must be interpreted as an >> IPv6 address without a port. This code however would take 8727 as the >> port and 2312::1234 as the IPv6 address, which is not what you >> expected >> (even after brackets are allowed - they don't make a difference >> because >> the example doesn't use brackets). > > In the migration context, host/port are all necessary, so it's right to parse "8272" to a port. > However, for IPv6 brackets must be mandatory if you require a port. Makes sense. > BTW, the DNS delay issue existed in the past (gethostbyname()), it should be fixed by another patchset. > I will post my V2 (without fix of DNS delay) later. Yes, I agree. Kevin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
