From: Eric Dumazet <eric.dumazet@gmail.com>
To: Saeed Mahameed <saeedm@mellanox.com>,
Jason Gunthorpe <jgg@ziepe.ca>,
Jianchao Wang <jianchao.w.wang@oracle.com>
Cc: tariqt@mellanox.com, junxiao.bi@oracle.com,
netdev@vger.kernel.org, linux-rdma@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net/mlx4_en: ensure rx_desc updating reaches HW before prod db updating
Date: Fri, 12 Jan 2018 13:21:59 -0800 [thread overview]
Message-ID: <1515792119.131759.52.camel@gmail.com> (raw)
In-Reply-To: <e902138a-3508-3504-51e5-46152cc2fb31@mellanox.com>
On Fri, 2018-01-12 at 13:01 -0800, Saeed Mahameed wrote:
> which is better to grasp ?:
>
> update_doorbell() {
> dma_wmb();
> ring->db = prod;
> }
This one is IMO the most secure one (least surprise)
Considering the time it took to discover this bug, I would really play
safe.
But obviously I do not maintain mlx4.
next prev parent reply other threads:[~2018-01-12 21:21 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-12 3:42 [PATCH] net/mlx4_en: ensure rx_desc updating reaches HW before prod db updating Jianchao Wang
2018-01-12 3:42 ` Jianchao Wang
2018-01-12 16:32 ` Jason Gunthorpe
[not found] ` <20180112163247.GB15974-uk2M96/98Pc@public.gmane.org>
2018-01-12 16:46 ` Eric Dumazet
2018-01-12 16:46 ` Eric Dumazet
2018-01-12 19:53 ` Saeed Mahameed
[not found] ` <85116e56-52b1-944d-6ee2-916ccfc3a7a6-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
2018-01-12 20:16 ` Eric Dumazet
2018-01-12 20:16 ` Eric Dumazet
2018-01-12 21:01 ` Saeed Mahameed
2018-01-12 21:21 ` Eric Dumazet [this message]
[not found] ` <e902138a-3508-3504-51e5-46152cc2fb31-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
2018-01-13 19:15 ` Jason Gunthorpe
2018-01-13 19:15 ` Jason Gunthorpe
2018-01-14 2:40 ` jianchao.wang
[not found] ` <a40e44f4-106b-1075-8f92-f7741508372c-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-14 9:47 ` Tariq Toukan
2018-01-14 9:47 ` Tariq Toukan
2018-01-15 5:50 ` jianchao.wang
[not found] ` <fea0aa1c-b68e-9485-3826-2dfad7824911-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-19 15:16 ` jianchao.wang
2018-01-19 15:16 ` jianchao.wang
[not found] ` <53b1ac4d-a294-eb98-149e-65d7954243da-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-19 15:49 ` Eric Dumazet
2018-01-19 15:49 ` Eric Dumazet
2018-01-21 9:31 ` Tariq Toukan
[not found] ` <dfc02a48-7d2a-56da-dc4e-d90a9fcc559c-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
2018-01-21 16:24 ` Tariq Toukan
2018-01-21 16:24 ` Tariq Toukan
2018-01-21 16:43 ` Eric Dumazet
[not found] ` <1516552998.3478.5.camel-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2018-01-22 2:40 ` jianchao.wang
2018-01-22 2:40 ` jianchao.wang
2018-01-22 15:47 ` Jason Gunthorpe
2018-01-23 3:25 ` jianchao.wang
2018-01-22 2:12 ` jianchao.wang
[not found] ` <c8b0955b-a3fc-afe2-2c67-e655ca2ee6f6-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-25 3:27 ` jianchao.wang
2018-01-25 3:27 ` jianchao.wang
[not found] ` <532b4d71-e2eb-35f3-894e-1c3288e7bc3f-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-25 3:55 ` Eric Dumazet
2018-01-25 3:55 ` Eric Dumazet
[not found] ` <1516852543.3715.43.camel-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2018-01-25 6:25 ` jianchao.wang
2018-01-25 6:25 ` jianchao.wang
[not found] ` <89066a75-43db-0f62-f171-70b0abaa8ea0-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2018-01-25 9:54 ` Tariq Toukan
2018-01-25 9:54 ` Tariq Toukan
[not found] ` <918db4ec-8c3c-aafa-4be6-0e00a99632e2-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
2018-01-27 12:41 ` jianchao.wang
2018-01-27 12:41 ` jianchao.wang
[not found] ` <d9883261-e93e-400a-757c-3a81d8b6aca1@mellanox.com>
2019-01-02 1:43 ` jianchao.wang
2018-01-21 20:40 ` Jason Gunthorpe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1515792119.131759.52.camel@gmail.com \
--to=eric.dumazet@gmail.com \
--cc=jgg@ziepe.ca \
--cc=jianchao.w.wang@oracle.com \
--cc=junxiao.bi@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=saeedm@mellanox.com \
--cc=tariqt@mellanox.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.