netdev - Re: [PATCH net-next v3 13/14] dibs: Move data path to dibs layer: manual merge

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <74368a5c-48ac-4f8e-a198-40ec1ed3cf5f@kernel.org>
Date: Wed, 24 Sep 2025 10:07:35 +0100
From: Matthieu Baerts <matttbe@...nel.org>
To: Alexandra Winter <wintera@...ux.ibm.com>,
 Sidraya Jayagond <sidraya@...ux.ibm.com>
Cc: Julian Ruess <julianr@...ux.ibm.com>,
 Aswin Karuvally <aswin@...ux.ibm.com>, Halil Pasic <pasic@...ux.ibm.com>,
 Mahanta Jambigi <mjambigi@...ux.ibm.com>, Tony Lu
 <tonylu@...ux.alibaba.com>, Wen Gu <guwen@...ux.alibaba.com>,
 linux-rdma@...r.kernel.org, netdev@...r.kernel.org,
 linux-s390@...r.kernel.org, Heiko Carstens <hca@...ux.ibm.com>,
 Vasily Gorbik <gor@...ux.ibm.com>, Alexander Gordeev
 <agordeev@...ux.ibm.com>, Christian Borntraeger <borntraeger@...ux.ibm.com>,
 Sven Schnelle <svens@...ux.ibm.com>, Simon Horman <horms@...nel.org>,
 Eric Biggers <ebiggers@...nel.org>, Ard Biesheuvel <ardb@...nel.org>,
 Herbert Xu <herbert@...dor.apana.org.au>,
 Harald Freudenberger <freude@...ux.ibm.com>,
 Konstantin Shkolnyy <kshk@...ux.ibm.com>,
 Dan Williams <dan.j.williams@...el.com>, Dave Jiang <dave.jiang@...el.com>,
 Jonathan Cameron <Jonathan.Cameron@...wei.com>,
 Shannon Nelson <sln@...main.com>, Geert Uytterhoeven <geert@...ux-m68k.org>,
 Jason Gunthorpe <jgg@...pe.ca>, "D. Wythe" <alibuda@...ux.alibaba.com>,
 Dust Li <dust.li@...ux.alibaba.com>, Wenjia Zhang <wenjia@...ux.ibm.com>,
 David Miller <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>,
 Paolo Abeni <pabeni@...hat.com>, Eric Dumazet <edumazet@...gle.com>,
 Andrew Lunn <andrew+netdev@...n.ch>, Stephen Rothwell <sfr@...b.auug.org.au>
Subject: Re: [PATCH net-next v3 13/14] dibs: Move data path to dibs layer:
 manual merge

Hi Alexandra, Sidraya,

On 18/09/2025 12:04, Alexandra Winter wrote:
> Use struct dibs_dmb instead of struct smc_dmb and move the corresponding
> client tables to dibs_dev. Leave driver specific implementation details
> like sba in the device drivers.
> 
> Register and unregister dmbs via dibs_dev_ops. A dmb is dedicated to a
> single client, but a dibs device can have dmbs for more than one client.
> 
> Trigger dibs clients via dibs_client_ops->handle_irq(), when data is
> received into a dmb. For dibs_loopback replace scheduling an smcd receive
> tasklet with calling dibs_client_ops->handle_irq().
> 
> For loopback devices attach_dmb(), detach_dmb() and move_data() need to
> access the dmb tables, so move those to dibs_dev_ops in this patch as well.
> 
> Remove remaining definitions of smc_loopback as they are no longer
> required, now that everything is in dibs_loopback.
> 
> Note that struct ism_client and struct ism_dev are still required in smc
> until a follow-on patch moves event handling to dibs. (Loopback does not
> use events).

FYI, we got a conflict when merging 'net' in 'net-next' in the MPTCP
tree due to this patch applied in 'net':

  a35c04de2565 ("net/smc: fix warning in smc_rx_splice() when calling
get_page()")

and this one from 'net-next':

  cc21191b584c ("dibs: Move data path to dibs layer")

----- Generic Message -----
The best is to avoid conflicts between 'net' and 'net-next' trees but if
they cannot be avoided when preparing patches, a note about how to fix
them is much appreciated.
The conflict has been resolved on our side[1] and the resolution we
suggest is attached to this email. Please report any issues linked to
this conflict resolution as it might be used by others. If you worked on
the mentioned patches, don't hesitate to ACK this conflict resolution.
---------------------------

Regarding this conflict, I hope the resolution is correct. The patch
from 'net' was modifying 'net/smc/smc_loopback.c' in
smc_lo_register_dmb() and __smc_lo_unregister_dmb(). I applied the same
modifications in 'drivers/dibs/dibs_loopback.c', in
dibs_lo_register_dmb() and __dibs_lo_unregister_dmb(). In net-next,
kfree(cpu_addr) was used instead of kvfree(cpu_addr), but this was done
on purpose. Also, I had to include mm.h to be able to build this driver.
I also attached a simple diff of the modifications I did.

Does that look OK to both of you?

Note: no rerere cache is available for this kind of conflicts.

Cheers,
Matt

[1] https://github.com/multipath-tcp/mptcp_net-next/commit/af2dbdbb0a91
-- 
Sponsored by the NGI0 Core fund.

View attachment "af2dbdbb0a91d92af6248888b566b8b154ebce6d.patch" of type "text/x-patch" (9619 bytes)

View attachment "conflict_dibs.patch" of type "text/x-patch" (1658 bytes)