From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Laight Date: Fri, 13 Sep 2019 08:36:22 +0000 Subject: RE: [PATCH net-next 5/5] sctp: add spt_pathcpthld in struct sctp_paddrthlds Message-Id: List-Id: References: <604e6ac718c29aa5b1a8c4b164a126b82bc42a2f.1568015756.git.lucien.xin@gmail.com> <9fc7ca1598e641cda3914840a4416aab@AcuMS.aculab.com> <1e5c3163e6c649b09137eeb62d193d87@AcuMS.aculab.com> <20190911125609.GC3499@localhost.localdomain> <20190912225154.GF3499@localhost.localdomain> In-Reply-To: <20190912225154.GF3499@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: 'Marcelo Ricardo Leitner' , Xin Long Cc: network dev , "linux-sctp@vger.kernel.org" , Neil Horman , "davem@davemloft.net" From: Marcelo Ricardo Leitner > Sent: 12 September 2019 23:52 ... > Here it is more visible. If net->...ps_retrans is disabled, remaining > fields (currently just this one, but as we are extending it now, we > have to think about the possibility of more as well) will be ignored, > we and we may not want that. The only real way to add additional fields is to change the name of the structure - that way recompiled programs still work. You could require that programs zero the entire structure - but that is difficult to verify. And, in this case, it seems that the default has to be 0xffff rather than 0 - which is, in itself, horrid. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)