From: James Nylen <jnylen@gmail.com>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>,
linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] `iwlist scan` fails with many networks available
Date: Tue, 13 Aug 2019 00:43:02 +0000 [thread overview]
Message-ID: <CABVa4Nga1vyvyWNpTTJLa44rZo8wu4-bE=mXX1nZgvzktbSq6A@mail.gmail.com> (raw)
In-Reply-To: <f7de98001849bc98a0a084d2ffc369f4d9772d52.camel@sipsolutions.net>
>I suppose we could consider applying a workaround like this if it has a
>condition checking that the buffer passed in is the maximum possible
>buffer (65535 bytes, due to iw_point::length being u16)
This is what the latest patch does (attached to my email from
yesterday / https://lkml.org/lkml/2019/8/10/452 ).
If you'd like to apply it, I'm happy to make any needed revisions.
Otherwise I'm going to have to keep patching my kernels for this
issue, unfortunately I don't have the time to try to get wicd to
migrate to a better solution.
On 8/11/19, Johannes Berg <johannes@sipsolutions.net> wrote:
> On Sun, 2019-08-11 at 02:08 +0000, James Nylen wrote:
>> In 5.x it's still possible for `ieee80211_scan_results` (`iwlist
>> scan`) to fail when too many wireless networks are available. This
>> code path is used by `wicd`.
>>
>> Previously: https://lkml.org/lkml/2017/4/2/192
>
> This has been known for probably a decade or longer. I don't know why
> 'wicd' still insists on using wext, unless it's no longer maintained at
> all. nl80211 doesn't have this problem at all, and I think gives more
> details about the networks found too.
>
>> I've been applying this updated patch to my own kernels since 2017 with
>> no issues. I am sure it is not the ideal way to solve this problem, but
>> I'm making my fix available in case it helps others.
>
> I don't think silently dropping data is a good solution.
>
> I suppose we could consider applying a workaround like this if it has a
> condition checking that the buffer passed in is the maximum possible
> buffer (65535 bytes, due to iw_point::length being u16), but below that
> -E2BIG serves well-written implementations as an indicator that they
> need to retry with a bigger buffer.
>
>> Please advise on next steps or if this is a dead end.
>
> I think wireless extensions are in fact a dead end and all software
> (even 'wicd', which seems to be the lone holdout) should migrate to
> nl80211 instead.
>
> johannes
>
>
next prev parent reply other threads:[~2019-08-13 0:43 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CABVa4NgWMkJuyB1P5fwQEYHwqBRiySE+fGQpMKt8zbp+xJ8+rw@mail.gmail.com>
2019-08-11 2:08 ` [PATCH] `iwlist scan` fails with many networks available James Nylen
2019-08-11 6:25 ` Johannes Berg
2019-08-13 0:43 ` James Nylen [this message]
2019-08-21 7:59 ` Johannes Berg
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