On 11/14/17 1:24 PM, Jon Maloy wrote: > > >> -----Original Message----- >> From: netdev-ow...@vger.kernel.org [mailto:netdev- >> ow...@vger.kernel.org] On Behalf Of David Ahern >> Sent: Tuesday, November 14, 2017 15:18 >> To: Jon Maloy <jon.ma...@ericsson.com>; netdev@vger.kernel.org; Jiri >> Pirko <j...@resnulli.us> >> Cc: David Miller (da...@davemloft.net) <da...@davemloft.net> >> Subject: Re: Broken netlink ABI >> >> On 11/14/17 1:15 PM, David Ahern wrote: >>> On 11/14/17 12:19 PM, Jon Maloy wrote: >>>> When I give the command: >>>> ~$ tipc node set addr 1.1.2 >>>> >>>> I get the following response: >>>> >>>> error: Numerical result out of range >>>> Unable to get TIPC nl family id (module loaded?) error, message >>>> initialisation failed >>> >>> tipc is sending a u32 for the family attribute when it should be a u16: >>> >>> diff --git a/tipc/msg.c b/tipc/msg.c >>> index 22c22226bb20..dc09d05048f3 100644 >>> --- a/tipc/msg.c >>> +++ b/tipc/msg.c >>> @@ -125,7 +125,7 @@ static int get_family(void) >>> genl->cmd = CTRL_CMD_GETFAMILY; >>> genl->version = 1; >>> >>> - mnl_attr_put_u32(nlh, CTRL_ATTR_FAMILY_ID, GENL_ID_CTRL); >>> + mnl_attr_put_u16(nlh, CTRL_ATTR_FAMILY_ID, GENL_ID_CTRL); >>> mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, >>> TIPC_GENL_V2_NAME); >>> >>> if ((err = msg_query(nlh, family_id_cb, &nl_family))) >>> >>> With the above change the tipc command runs fine. > > I can fix that, but that that doesn't change the fact that binaries that have > been around and worked flawlessly for years now all by sudden have stopped > working.
The command has to be broken on some platforms (big endian?); it is sending a u32 value which is truncated to u16 by the kernel. > Whether the user is doing right or wrong, that if for me the very definition > of a broken ABI, and is unacceptable. > > Either you have to remove the test in your patch, or you can try to identify > tipc and devlink in the code and exempt those from your test. > DaveM: opinions? I expected fallout like this. Should I just log a warning telling users they are running broken commands?
