[MPTCP] Patch does not apply

[MPTCP] Patch does not apply

[Rao Shoaib]

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I am unable to apply the 6th patch.

rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am 
"/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs - 
Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
Applying: mptcp: Add MPTCP socket stubs
.git/rebase-apply/patch:87: new blank line at EOF.
+
warning: 1 line adds whitespace errors.

rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am 
"/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and 
structs for MPTCP - Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 
2018-03-28 1618.eml"
Applying: tcp: expose tcp routines and structs for MPTCP
error: patch failed: include/net/inet_common.h:35
error: include/net/inet_common.h: patch does not apply
Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
The copy of the patch that failed is found in: .git/rebase-apply/patch
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git remote -v
origin 
https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git (fetch)
origin 
https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git (push)

Shoaib

Re: [MPTCP] Patch does not apply

[Rao Shoaib]

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On 03/30/2018 11:25 AM, Krystad, Peter wrote:
>
>>> I think the intention with this patchset was to show how the struct prot
>>> and exposing MPTCP fully at the socket layer allows to simplify things.
>> It does  not, Look at my patch, compare and post.
> I did look at your patchset. This one has ~200 lines of code change in
> net/ipv4/*.c, a very low impact, yours is >1000. While yours has more
> functionality this one is simpler, in the sense of having less obvious
> impact to TCP code.
Hi Peter,

No offense to you and Mat.
If I were to implement the same level of functionality I would make the 
same number of changes. I can take RDS code right now and create an 
MPTCP connection. That is all this patch does.

>
>>> Creation of a real struct socket for subflows is also going to help a lot,
>>> as that's the path forward to enable proper lock-separation. We can't take the
>>> meta-socket lock in the TCP-stack as I mentioned in my review to your
>>> patchset.
>>>
>>>
>>> So, in that sense for the above two points, the patchset is very useful as
>>> it shows how MPTCP fits in such a model.
>> It does not show anything because it does nothing.
> I beg to differ. The point of this patchset is to show, not do. We had
> direct feedback from the netdev maintainers that "something like KCM"
> would be of interest to them, this is an attempt at that.
>
KCM, RDS do not change TCP, they use it, as it is. KCM uses eBPF instead 
of adding code to TCP. MPTCP requires mucking with TCP processing, there 
is a lot of difference. If you can use KCM than please use it, even 
better if eBPF can be used. I am not sure about direct input from 
upstream. I am aware that a statement was made "maybe we can use KCM" 
and the response was, that would be great, that is the obvious response 
because the proposal is to use an existing functionality and it is 
implied that no mucking with TCP will be done.

The code is not there. I looked at MPTCP specific processing and do not 
see any change compared to the default implementation. There is talk 
about creating an interface to push the arguments up, once you keep 
adding these small changes, we will be where we are. All the interfaces 
needed are already present and they are very clean. Just look at the Rx 
path, after my cleanup it literally has no MPTCP specific code. I can 
even narrow down the branch taken in tcp_v4_rcv.

This is getting personal and controversial so I am going to refrain from 
any other comment. If you can provide a detailed design doc that sites 
the issues and the resolution I will be happy to review it. It would 
also be good to compare the two approaches.

Regards,

Shoaib

Re: [MPTCP] Patch does not apply

[Krystad, Peter]

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On Thu, 2018-03-29 at 12:01 -0700, Rao Shoaib wrote:
> 
> On 03/29/2018 11:12 AM, Christoph Paasch wrote:
> > On 29/03/18 - 10:41:08, Rao Shoaib wrote:
> > > On 03/29/2018 08:40 AM, Mat Martineau wrote:
> > > > On Wed, 28 Mar 2018, Rao Shoaib wrote:
> > > > > I am unable to apply the 6th patch.
> > > > > 
> > > > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am
> > > > > "/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs
> > > > > - Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28
> > > > > 1618.eml"
> > > > > Applying: mptcp: Add MPTCP socket stubs
> > > > > .git/rebase-apply/patch:87: new blank line at EOF.
> > > > > +
> > > > > warning: 1 line adds whitespace errors.
> > > > > 
> > > > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am
> > > > > "/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and
> > > > > structs for MPTCP - Mat Martineau
> > > > > <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
> > > > > Applying: tcp: expose tcp routines and structs for MPTCP
> > > > > error: patch failed: include/net/inet_common.h:35
> > > > > error: include/net/inet_common.h: patch does not apply
> > > > > Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
> > > > > The copy of the patch that failed is found in: .git/rebase-apply/patch
> > > > > When you have resolved this problem, run "git am --continue".
> > > > > If you prefer to skip this patch, run "git am --skip" instead.
> > > > > To restore the original branch and stop patching, run "git am --abort".
> > > > > 
> > > > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git
> > > > > remote -v
> > > > > origin
> > > > > https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
> > > > > (fetch)
> > > > > origin
> > > > > https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
> > > > > (push)
> > > > 
> > > > If you cloned my git.kernel.org repo (which appears to be the case from
> > > > your 'git remote -v' output), you shouldn't need to apply the patches
> > > > from email. Instead:
> > > > 
> > > > $ git checkout -t origin/mptcp-proposal
> > > > 
> > > > will get you the commits directly from the git server.
> > > > 
> > > > 
> > > > Just to be specific, to apply the patches from email instead of directly
> > > > checking out, you would clone
> > > > https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git and
> > > > apply the patches to that repository. In addition, I'm not 100% sure
> > > > 'git am' understands .eml files - the man page for the latest git
> > > > release mentions maildir, mbox, mboxrd, stgit, stgit-series and hg as
> > > > supported email formats.
> > > > 
> > > > Hope this helps!
> > > > 
> > > > -- 
> > > > Mat Martineau
> > > > Intel OTC
> > > 
> > > Hi Mat,
> > > 
> > > For some reason that was not clear to me, anyways I just looked at the
> > > patches and I am sorry to say I do not see any thing special about the
> > > patch.
> > > 
> > > For example the patch uses
> > > 
> > > +       .conn_request      = subflow_conn_request,
> > > +       .syn_recv_sock     = subflow_syn_recv_sock,
> > > 
> > > The original implementation used
> > > 
> > >          .conn_request      = mptcp_conn_request,
> > >          .syn_recv_sock     = tcp_v4_syn_recv_sock,
> > > 
> > > subflow_syn_recv_sock() calls tcp_v4_syn_recv_sock()
> > > 
> > > The patch handles options exactly the same way as they have always been
> > > handled. Old implementation had struct mptcp_request_sock the patch has
> > > struct subflow_request_sock.
> > > 
> > > The patch is incomplete as it can not exchange any data using MPTCP. I see
> > > no reason to use this approach, we have a working implementation and that
> > > should be used and improved upon.
> > 
> > I think the intention with this patchset was to show how the struct prot
> > and exposing MPTCP fully at the socket layer allows to simplify things.
> 
> It does  not, Look at my patch, compare and post.

I did look at your patchset. This one has ~200 lines of code change in
net/ipv4/*.c, a very low impact, yours is >1000. While yours has more
functionality this one is simpler, in the sense of having less obvious
impact to TCP code.

> > 
> > Creation of a real struct socket for subflows is also going to help a lot,
> > as that's the path forward to enable proper lock-separation. We can't take the
> > meta-socket lock in the TCP-stack as I mentioned in my review to your
> > patchset.
> > 
> > 
> > So, in that sense for the above two points, the patchset is very useful as
> > it shows how MPTCP fits in such a model.
> 
> It does not show anything because it does nothing.

I beg to differ. The point of this patchset is to show, not do. We had
direct feedback from the netdev maintainers that "something like KCM"
would be of interest to them, this is an attempt at that.

Regards,

Peter.
 
> 
> Rao.
> 
> > 
> > 
> > Christoph
> > 
> 
> _______________________________________________
> mptcp mailing list
> mptcp(a)lists.01.org
> https://lists.01.org/mailman/listinfo/mptcp

Re: [MPTCP] Patch does not apply

[Rao Shoaib]

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On 03/29/2018 11:12 AM, Christoph Paasch wrote:
> On 29/03/18 - 10:41:08, Rao Shoaib wrote:
>> On 03/29/2018 08:40 AM, Mat Martineau wrote:
>>> On Wed, 28 Mar 2018, Rao Shoaib wrote:
>>>> I am unable to apply the 6th patch.
>>>>
>>>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am
>>>> "/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs
>>>> - Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28
>>>> 1618.eml"
>>>> Applying: mptcp: Add MPTCP socket stubs
>>>> .git/rebase-apply/patch:87: new blank line at EOF.
>>>> +
>>>> warning: 1 line adds whitespace errors.
>>>>
>>>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am
>>>> "/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and
>>>> structs for MPTCP - Mat Martineau
>>>> <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
>>>> Applying: tcp: expose tcp routines and structs for MPTCP
>>>> error: patch failed: include/net/inet_common.h:35
>>>> error: include/net/inet_common.h: patch does not apply
>>>> Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
>>>> The copy of the patch that failed is found in: .git/rebase-apply/patch
>>>> When you have resolved this problem, run "git am --continue".
>>>> If you prefer to skip this patch, run "git am --skip" instead.
>>>> To restore the original branch and stop patching, run "git am --abort".
>>>>
>>>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git
>>>> remote -v
>>>> origin
>>>> https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
>>>> (fetch)
>>>> origin
>>>> https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
>>>> (push)
>>> If you cloned my git.kernel.org repo (which appears to be the case from
>>> your 'git remote -v' output), you shouldn't need to apply the patches
>>> from email. Instead:
>>>
>>> $ git checkout -t origin/mptcp-proposal
>>>
>>> will get you the commits directly from the git server.
>>>
>>>
>>> Just to be specific, to apply the patches from email instead of directly
>>> checking out, you would clone
>>> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git and
>>> apply the patches to that repository. In addition, I'm not 100% sure
>>> 'git am' understands .eml files - the man page for the latest git
>>> release mentions maildir, mbox, mboxrd, stgit, stgit-series and hg as
>>> supported email formats.
>>>
>>> Hope this helps!
>>>
>>> -- 
>>> Mat Martineau
>>> Intel OTC
>> Hi Mat,
>>
>> For some reason that was not clear to me, anyways I just looked at the
>> patches and I am sorry to say I do not see any thing special about the
>> patch.
>>
>> For example the patch uses
>>
>> +       .conn_request      = subflow_conn_request,
>> +       .syn_recv_sock     = subflow_syn_recv_sock,
>>
>> The original implementation used
>>
>>          .conn_request      = mptcp_conn_request,
>>          .syn_recv_sock     = tcp_v4_syn_recv_sock,
>>
>> subflow_syn_recv_sock() calls tcp_v4_syn_recv_sock()
>>
>> The patch handles options exactly the same way as they have always been
>> handled. Old implementation had struct mptcp_request_sock the patch has
>> struct subflow_request_sock.
>>
>> The patch is incomplete as it can not exchange any data using MPTCP. I see
>> no reason to use this approach, we have a working implementation and that
>> should be used and improved upon.
> I think the intention with this patchset was to show how the struct prot
> and exposing MPTCP fully at the socket layer allows to simplify things.
It does  not, Look at my patch, compare and post.
>
> Creation of a real struct socket for subflows is also going to help a lot,
> as that's the path forward to enable proper lock-separation. We can't take the
> meta-socket lock in the TCP-stack as I mentioned in my review to your
> patchset.
>
>
> So, in that sense for the above two points, the patchset is very useful as
> it shows how MPTCP fits in such a model.
It does not show anything because it does nothing.

Rao.

>
>
> Christoph
>

Re: [MPTCP] Patch does not apply

[Christoph Paasch]

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On 29/03/18 - 10:41:08, Rao Shoaib wrote:
> On 03/29/2018 08:40 AM, Mat Martineau wrote:
> > On Wed, 28 Mar 2018, Rao Shoaib wrote:
> > > I am unable to apply the 6th patch.
> > > 
> > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am
> > > "/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs
> > > - Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28
> > > 1618.eml"
> > > Applying: mptcp: Add MPTCP socket stubs
> > > .git/rebase-apply/patch:87: new blank line at EOF.
> > > +
> > > warning: 1 line adds whitespace errors.
> > > 
> > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am
> > > "/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and
> > > structs for MPTCP - Mat Martineau
> > > <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
> > > Applying: tcp: expose tcp routines and structs for MPTCP
> > > error: patch failed: include/net/inet_common.h:35
> > > error: include/net/inet_common.h: patch does not apply
> > > Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
> > > The copy of the patch that failed is found in: .git/rebase-apply/patch
> > > When you have resolved this problem, run "git am --continue".
> > > If you prefer to skip this patch, run "git am --skip" instead.
> > > To restore the original branch and stop patching, run "git am --abort".
> > > 
> > > rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git
> > > remote -v
> > > origin
> > > https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
> > > (fetch)
> > > origin
> > > https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git
> > > (push)
> > 
> > If you cloned my git.kernel.org repo (which appears to be the case from
> > your 'git remote -v' output), you shouldn't need to apply the patches
> > from email. Instead:
> > 
> > $ git checkout -t origin/mptcp-proposal
> > 
> > will get you the commits directly from the git server.
> > 
> > 
> > Just to be specific, to apply the patches from email instead of directly
> > checking out, you would clone
> > https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git and
> > apply the patches to that repository. In addition, I'm not 100% sure
> > 'git am' understands .eml files - the man page for the latest git
> > release mentions maildir, mbox, mboxrd, stgit, stgit-series and hg as
> > supported email formats.
> > 
> > Hope this helps!
> > 
> > -- 
> > Mat Martineau
> > Intel OTC
> Hi Mat,
> 
> For some reason that was not clear to me, anyways I just looked at the
> patches and I am sorry to say I do not see any thing special about the
> patch.
> 
> For example the patch uses
> 
> +       .conn_request      = subflow_conn_request,
> +       .syn_recv_sock     = subflow_syn_recv_sock,
> 
> The original implementation used
> 
>         .conn_request      = mptcp_conn_request,
>         .syn_recv_sock     = tcp_v4_syn_recv_sock,
> 
> subflow_syn_recv_sock() calls tcp_v4_syn_recv_sock()
> 
> The patch handles options exactly the same way as they have always been
> handled. Old implementation had struct mptcp_request_sock the patch has
> struct subflow_request_sock.
> 
> The patch is incomplete as it can not exchange any data using MPTCP. I see
> no reason to use this approach, we have a working implementation and that
> should be used and improved upon.

I think the intention with this patchset was to show how the struct prot
and exposing MPTCP fully at the socket layer allows to simplify things.

Creation of a real struct socket for subflows is also going to help a lot,
as that's the path forward to enable proper lock-separation. We can't take the
meta-socket lock in the TCP-stack as I mentioned in my review to your
patchset.


So, in that sense for the above two points, the patchset is very useful as
it shows how MPTCP fits in such a model.


Christoph

Re: [MPTCP] Patch does not apply

[Rao Shoaib]

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On 03/29/2018 08:40 AM, Mat Martineau wrote:
>
> Hi Rao -
>
> On Wed, 28 Mar 2018, Rao Shoaib wrote:
>
>> I am unable to apply the 6th patch.
>>
>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am 
>> "/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs - 
>> Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 
>> 1618.eml"
>> Applying: mptcp: Add MPTCP socket stubs
>> .git/rebase-apply/patch:87: new blank line at EOF.
>> +
>> warning: 1 line adds whitespace errors.
>>
>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am 
>> "/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and 
>> structs for MPTCP - Mat Martineau 
>> <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
>> Applying: tcp: expose tcp routines and structs for MPTCP
>> error: patch failed: include/net/inet_common.h:35
>> error: include/net/inet_common.h: patch does not apply
>> Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
>> The copy of the patch that failed is found in: .git/rebase-apply/patch
>> When you have resolved this problem, run "git am --continue".
>> If you prefer to skip this patch, run "git am --skip" instead.
>> To restore the original branch and stop patching, run "git am --abort".
>>
>> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git 
>> remote -v
>> origin 
>> https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git 
>> (fetch)
>> origin 
>> https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git 
>> (push)
>
> If you cloned my git.kernel.org repo (which appears to be the case 
> from your 'git remote -v' output), you shouldn't need to apply the 
> patches from email. Instead:
>
> $ git checkout -t origin/mptcp-proposal
>
> will get you the commits directly from the git server.
>
>
> Just to be specific, to apply the patches from email instead of 
> directly checking out, you would clone 
> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git and 
> apply the patches to that repository. In addition, I'm not 100% sure 
> 'git am' understands .eml files - the man page for the latest git 
> release mentions maildir, mbox, mboxrd, stgit, stgit-series and hg as 
> supported email formats.
>
> Hope this helps!
>
> -- 
> Mat Martineau
> Intel OTC
Hi Mat,

For some reason that was not clear to me, anyways I just looked at the 
patches and I am sorry to say I do not see any thing special about the 
patch.

For example the patch uses

+       .conn_request      = subflow_conn_request,
+       .syn_recv_sock     = subflow_syn_recv_sock,

The original implementation used

         .conn_request      = mptcp_conn_request,
         .syn_recv_sock     = tcp_v4_syn_recv_sock,

subflow_syn_recv_sock() calls tcp_v4_syn_recv_sock()

The patch handles options exactly the same way as they have always been 
handled. Old implementation had struct mptcp_request_sock the patch has 
struct subflow_request_sock.

The patch is incomplete as it can not exchange any data using MPTCP. I 
see no reason to use this approach, we have a working implementation and 
that should be used and improved upon.

Shoaib

Re: [MPTCP] Patch does not apply

[Mat Martineau]

[-- Attachment #1: Type: text/plain, Size: 2242 bytes --]


Hi Rao -

On Wed, 28 Mar 2018, Rao Shoaib wrote:

> I am unable to apply the 6th patch.
>
> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux.old(master)$git am 
> "/tmp/mails/[MPTCP] [RFC PATCH 03_16] mptcp: Add MPTCP socket stubs - Mat 
> Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 1618.eml"
> Applying: mptcp: Add MPTCP socket stubs
> .git/rebase-apply/patch:87: new blank line at EOF.
> +
> warning: 1 line adds whitespace errors.
>
> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master)$git am 
> "/tmp/mails/[MPTCP] [RFC PATCH 06_16] tcp: expose tcp routines and structs 
> for MPTCP - Mat Martineau <mathew.j.martineau(a)linux.intel.com> - 2018-03-28 
> 1618.eml"
> Applying: tcp: expose tcp routines and structs for MPTCP
> error: patch failed: include/net/inet_common.h:35
> error: include/net/inet_common.h: patch does not apply
> Patch failed at 0001 tcp: expose tcp routines and structs for MPTCP
> The copy of the patch that failed is found in: .git/rebase-apply/patch
> When you have resolved this problem, run "git am --continue".
> If you prefer to skip this patch, run "git am --skip" instead.
> To restore the original branch and stop patching, run "git am --abort".
>
> rshoaib(a)caduceus5:/home/mptcp/sock_mptcp/linux(master|AM 1/1)$git remote -v
> origin https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git 
> (fetch)
> origin https://git.kernel.org/pub/scm/linux/kernel/git/martineau/linux.git 
> (push)

If you cloned my git.kernel.org repo (which appears to be the case from 
your 'git remote -v' output), you shouldn't need to apply the patches from 
email. Instead:

$ git checkout -t origin/mptcp-proposal

will get you the commits directly from the git server.


Just to be specific, to apply the patches from email instead of directly 
checking out, you would clone 
https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git and 
apply the patches to that repository. In addition, I'm not 100% sure 'git 
am' understands .eml files - the man page for the latest git release 
mentions maildir, mbox, mboxrd, stgit, stgit-series and hg as supported 
email formats.

Hope this helps!

--
Mat Martineau
Intel OTC