From: Paolo Abeni <pabeni@redhat.com>
To: Andrew Lunn <andrew@lunn.ch>, Yeounsu Moon <yyyynoom@gmail.com>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>,
"David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: dlink: mask rx_coalesce/rx_timeout before writing RxDMAIntCtrl
Date: Tue, 30 Dec 2025 11:57:37 +0100 [thread overview]
Message-ID: <73f3d573-c093-469b-ac7e-36fdb7832933@redhat.com> (raw)
In-Reply-To: <ca3335ea-b9cd-4158-91a3-758cba9df804@lunn.ch>
On 12/23/25 10:43 AM, Andrew Lunn wrote:
> On Tue, Dec 23, 2025 at 09:10:06AM +0900, Yeounsu Moon wrote:
>> RxDMAIntCtrl encodes rx_coalesce in the low 16 bits
>> and rx_timeout in the high 16 bits. If either value exceeds
>> the field width, the current code may truncate the value and/or
>> corrupt adjacent bits when programming the register.
>>
>> Mask both values to 16 bits and cast to u32 before shifting
>> so only the intended fields are written.
>
> It would be better to do range checks in rio_probe1() and call
> netdev_err() and return -EINVAL?
>
> Anybody trying to use very large values then gets an error message
> rather than it working, but not as expected.
I'm not sure we can do such change: any eventual user with bad setting
will get a broken setup after kernel update. I think we should avoid
such regression, and use something similar to this patch.
@Yeounsu: the type cast in the current patch is not needed, please drop
it, thanks!
Paolo
prev parent reply other threads:[~2025-12-30 10:57 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-23 0:10 [PATCH net] net: dlink: mask rx_coalesce/rx_timeout before writing RxDMAIntCtrl Yeounsu Moon
2025-12-23 9:43 ` Andrew Lunn
2025-12-27 8:55 ` Yeounsu Moon
2025-12-30 10:57 ` Paolo Abeni [this message]
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=73f3d573-c093-469b-ac7e-36fdb7832933@redhat.com \
--to=pabeni@redhat.com \
--cc=andrew+netdev@lunn.ch \
--cc=andrew@lunn.ch \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=yyyynoom@gmail.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).