Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-02 Thread Rick Jones
On 04/01/2016 07:21 PM, Eric Dumazet wrote: On Fri, 2016-04-01 at 22:16 -0400, David Miller wrote: From: Alexander Duyck Date: Fri, 1 Apr 2016 12:58:41 -0700 RFC 6864 is pretty explicit about this, IPv4 ID used only for fragmentation.

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-02 Thread Alexander Duyck
On Fri, Apr 1, 2016 at 7:16 PM, David Miller wrote: > From: Alexander Duyck > Date: Fri, 1 Apr 2016 12:58:41 -0700 > >> RFC 6864 is pretty explicit about this, IPv4 ID used only for >> fragmentation. https://tools.ietf.org/html/rfc6864#section-4.1

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Eric Dumazet
On Sat, 2016-04-02 at 10:19 +0800, Herbert Xu wrote: > On Fri, Apr 01, 2016 at 07:15:33PM -0700, Eric Dumazet wrote: > > On Sat, 2016-04-02 at 09:57 +0800, Herbert Xu wrote: > > > > > > We could easily fix that by adding a feature bit to control this, > > > something like SKB_GSO_TCP_FIXEDID. > >

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Eric Dumazet
On Fri, 2016-04-01 at 22:16 -0400, David Miller wrote: > From: Alexander Duyck > Date: Fri, 1 Apr 2016 12:58:41 -0700 > > > RFC 6864 is pretty explicit about this, IPv4 ID used only for > > fragmentation. https://tools.ietf.org/html/rfc6864#section-4.1 > > > > The

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Herbert Xu
On Fri, Apr 01, 2016 at 07:15:33PM -0700, Eric Dumazet wrote: > On Sat, 2016-04-02 at 09:57 +0800, Herbert Xu wrote: > > > > We could easily fix that by adding a feature bit to control this, > > something like SKB_GSO_TCP_FIXEDID. > > I understood the patch allowed to aggregate 4 segments having

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread David Miller
From: Alexander Duyck Date: Fri, 1 Apr 2016 12:58:41 -0700 > RFC 6864 is pretty explicit about this, IPv4 ID used only for > fragmentation. https://tools.ietf.org/html/rfc6864#section-4.1 > > The goal with this change is to try and keep most of the existing >

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Eric Dumazet
On Sat, 2016-04-02 at 09:57 +0800, Herbert Xu wrote: > Eric Dumazet wrote: > > > > I do not particularly care, but it is worth mentioning that GRO+TSO > > would not be idempotent anymore. > > We could easily fix that by adding a feature bit to control this, > something

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Herbert Xu
Eric Dumazet wrote: > > I do not particularly care, but it is worth mentioning that GRO+TSO > would not be idempotent anymore. We could easily fix that by adding a feature bit to control this, something like SKB_GSO_TCP_FIXEDID. Cheers, -- Email: Herbert Xu

RE: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Subash Abhinov Kasiviswanathan
| For transmit we can leave the IP ID code as is. For receive we should not be | snooping into the IP ID for any frames that have the DF bit set as devices | that have adopted RFC 6864 on their transmit path will end up causing issues. Currently, GRO does not coalesce TCP packets originating

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Alexander Duyck
On Fri, Apr 1, 2016 at 12:24 PM, David Miller wrote: > From: Eric Dumazet > Date: Fri, 01 Apr 2016 11:49:03 -0700 > >> For example, TCP stack tracks per socket ID generation, even if it >> sends DF=1 frames. Damn useful for tcpdump analysis and drop

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread David Miller
From: Eric Dumazet Date: Fri, 01 Apr 2016 11:49:03 -0700 > For example, TCP stack tracks per socket ID generation, even if it > sends DF=1 frames. Damn useful for tcpdump analysis and drop > inference. Thanks for mentioning this, I never considered this use case. > With

Re: [net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Eric Dumazet
On Fri, 2016-04-01 at 11:05 -0700, Alexander Duyck wrote: > RFC 6864 states that the IPv4 ID field MUST NOT be used for purposes other > than fragmentation and reassembly. Currently we are looking at this field > as a way of identifying what frames can be aggregated and which cannot for > GRO.

[net PATCH 2/2] ipv4/GRO: Make GRO conform to RFC 6864

2016-04-01 Thread Alexander Duyck
RFC 6864 states that the IPv4 ID field MUST NOT be used for purposes other than fragmentation and reassembly. Currently we are looking at this field as a way of identifying what frames can be aggregated and which cannot for GRO. While this is valid for frames that do not have DF set, it is