From mboxrd@z Thu Jan 1 00:00:00 1970 From: Doug Ledford Subject: Re: [PATCH] net/smc: mark as BROKEN due to remote memory exposure Date: Tue, 16 May 2017 15:28:19 -0400 Message-ID: <1494962899.3259.141.camel@redhat.com> References: <1494955244.3259.130.camel@redhat.com> <20170516.133644.850927380166261577.davem@davemloft.net> <1494957802.3259.131.camel@redhat.com> <20170516.145249.871010194359061722.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20170516.145249.871010194359061722.davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: David Miller Cc: Bart.VanAssche-XdAiOPVOjttBDgjK7y7TUQ@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, hch-jcswGhMUV9g@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ubraun-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Tue, 2017-05-16 at 14:52 -0400, David Miller wrote: > From: Doug Ledford > Date: Tue, 16 May 2017 14:03:22 -0400 > > > On Tue, 2017-05-16 at 13:36 -0400, David Miller wrote: > >> From: Doug Ledford > >> Date: Tue, 16 May 2017 13:20:44 -0400 > >>  > >> > Anyway, we're just talking out what happened, when what we > really > >> need > >> > to focus on is moving forward.  Again, your thoughts on marking > SMC > >> > EXPERIMENTAL until it's fixed up and unfreezing the API in case > we > >> need > >> > to adjust it to work on different link layers? > >>  > >> Something like: > >>  > >>         http://patchwork.ozlabs.org/patch/762803/ > >>  > >> with the addition of the EXPERIMENTAL dependency? > >>  > >> Sure. > >  > > Perfect.  I assume you'll submit it since it's in your patchworks? > > Ok I applied the patch referenced above, but we don't actually have > an EXPERIMENTAL symbol.  The closest thing we have is BROKEN and > even in this situation that's a bit harsh. I hadn't realized EXPERIMENTAL was gone.  Which is too bad, because that's entirely appropriate in this case, and would have had the desired side effect of keeping it out of any non-cutting edge distros and warning people of possible API changes.  With EXPERIMENTAL gone, the closest thing we have is drivers/staging, since that tends to imply some of the same consequences.  I know you think BROKEN is overly harsh, but I'm not sure we should just do nothing.  How about we take a few days to let some of the RDMA people closely review the 143 page (egads!) rfc (http://www.rfc-editor.org/info/rfc7609) to see if we think it can be fixed to use multiple link layers with the existing API in place or if it will require something other than AF_SMC.  If we need to break API, then I think we should either fix it ASAP and send that fix to the 4.11 stable series (which probably violates the normative stable patch size/scope) or if the fix will take longer than this kernel cycle, then move it to staging both here and in 4.11 stable, and fix it there and then move it back.  Something like that would prevent the kind of API flappage we ought not do.... -- Doug Ledford     GPG KeyID: B826A3330E572FDD     Key fingerprint = AE6B 1BDA 122B 23B4 265B  1274 B826 A333 0E57 2FDD -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:40738 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751272AbdEPT22 (ORCPT ); Tue, 16 May 2017 15:28:28 -0400 Message-ID: <1494962899.3259.141.camel@redhat.com> Subject: Re: [PATCH] net/smc: mark as BROKEN due to remote memory exposure From: Doug Ledford To: David Miller Cc: Bart.VanAssche@sandisk.com, torvalds@linux-foundation.org, hch@lst.de, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, stable@vger.kernel.org, ubraun@linux.vnet.ibm.com Date: Tue, 16 May 2017 15:28:19 -0400 In-Reply-To: <20170516.145249.871010194359061722.davem@davemloft.net> References: <1494955244.3259.130.camel@redhat.com> <20170516.133644.850927380166261577.davem@davemloft.net> <1494957802.3259.131.camel@redhat.com> <20170516.145249.871010194359061722.davem@davemloft.net> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: On Tue, 2017-05-16 at 14:52 -0400, David Miller wrote: > From: Doug Ledford > Date: Tue, 16 May 2017 14:03:22 -0400 > > > On Tue, 2017-05-16 at 13:36 -0400, David Miller wrote: > >> From: Doug Ledford > >> Date: Tue, 16 May 2017 13:20:44 -0400 > >>  > >> > Anyway, we're just talking out what happened, when what we > really > >> need > >> > to focus on is moving forward.  Again, your thoughts on marking > SMC > >> > EXPERIMENTAL until it's fixed up and unfreezing the API in case > we > >> need > >> > to adjust it to work on different link layers? > >>  > >> Something like: > >>  > >>         http://patchwork.ozlabs.org/patch/762803/ > >>  > >> with the addition of the EXPERIMENTAL dependency? > >>  > >> Sure. > >  > > Perfect.  I assume you'll submit it since it's in your patchworks? > > Ok I applied the patch referenced above, but we don't actually have > an EXPERIMENTAL symbol.  The closest thing we have is BROKEN and > even in this situation that's a bit harsh. I hadn't realized EXPERIMENTAL was gone.  Which is too bad, because that's entirely appropriate in this case, and would have had the desired side effect of keeping it out of any non-cutting edge distros and warning people of possible API changes.  With EXPERIMENTAL gone, the closest thing we have is drivers/staging, since that tends to imply some of the same consequences.  I know you think BROKEN is overly harsh, but I'm not sure we should just do nothing.  How about we take a few days to let some of the RDMA people closely review the 143 page (egads!) rfc (http://www.rfc-editor.org/info/rfc7609) to see if we think it can be fixed to use multiple link layers with the existing API in place or if it will require something other than AF_SMC.  If we need to break API, then I think we should either fix it ASAP and send that fix to the 4.11 stable series (which probably violates the normative stable patch size/scope) or if the fix will take longer than this kernel cycle, then move it to staging both here and in 4.11 stable, and fix it there and then move it back.  Something like that would prevent the kind of API flappage we ought not do.... -- Doug Ledford     GPG KeyID: B826A3330E572FDD     Key fingerprint = AE6B 1BDA 122B 23B4 265B  1274 B826 A333 0E57 2FDD