linux-wireless.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Michael Büsch" <m@bues.ch>
To: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Rui Salvaterra <rsalvaterra@gmail.com>,
	linux-wireless@vger.kernel.org, b43-dev@lists.infradead.org
Subject: Re: [BUG?] b43: can't connect to WPA3 network (nohwcrypt=1)
Date: Fri, 22 May 2020 12:19:10 +0200	[thread overview]
Message-ID: <20200522121910.254aefc1@wiggum> (raw)
In-Reply-To: <f6152cd7-1043-dde2-7fc1-634d8b07a231@lwfinger.net>

[-- Attachment #1: Type: text/plain, Size: 2049 bytes --]

On Thu, 21 May 2020 16:47:41 -0500
Larry Finger <Larry.Finger@lwfinger.net> wrote:

> On 5/21/20 3:23 PM, Rui Salvaterra wrote:
> > On Thu, 21 May 2020 at 20:19, Rui Salvaterra <rsalvaterra@gmail.com> wrote:  
> >>
> >> Sure, I'll give it a spin. I'm now compiling the kernel for the laptop
> >> with the other b43 card (BCM4311).  
> > 
> > Nope, kmsg is clean. I'm pretty sure the condition is evaluating to
> > false because we do have the firmware, it's just that the crypto
> > engine doesn't support the required algo.
> > Is hardware encryption an all-or-nothing thing in mac80211? Wouldn't
> > it be possible use the hardware as much as possible and fall back to
> > software only for the unsupported features? (I guess the answer is
> > "no, because the firmware gets in the way", but I had to ask.)
> >   
> 
> My first failure indicates the mac80211 needs to know from the start that 
> software encryption is to be used. The only places that the driver makes note of 
> the nohwcrypt is in b43_op_set_key() where it returns -ENOSPC, and our new one 
> where MFP_CAPABLE is set. Otherwise, the packet flags indicate that encryption 
> is not needed.


Thank you all very much for benchmarking this.

As we see, hwcrypto has a major effect on CPU load.
But I'm still in favor of changing the default to nohwcrypt=1.
That would be a trade off between a wifi that does work with "bad"
performance vs. a wifi that does not work at all by default. It would
not stop people from enabling hwcrypto again.

But I'm also wondering, if we can dynamically decide whether to allow
hwcrypto.
Can't we set the MFP-flag all the time and then in b43_op_set_key
decide whether we allow hwcrypto or not? As far as I remember mac80211
falls back to sw-crypto, if an error is returned from the key op. So it
would "just" be a matter of detecting whether MFP is actually being
used in the network we are trying to connect to from within the key op.
Is that information available somewhere in mac80211?

-- 
Michael

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

  reply	other threads:[~2020-05-22 10:20 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-19 14:18 [BUG?] b43: can't connect to WPA3 network (nohwcrypt=1) Rui Salvaterra
2020-05-19 20:30 ` Larry Finger
2020-05-19 20:36   ` Rui Salvaterra
2020-05-19 23:13     ` Rui Salvaterra
2020-05-20  0:16       ` Larry Finger
2020-05-20  8:24         ` Rui Salvaterra
2020-05-20 10:55           ` Rui Salvaterra
2020-05-20 20:08             ` Larry Finger
2020-05-20 20:28               ` Rui Salvaterra
2020-05-20 20:56                 ` Larry Finger
2020-05-21  8:35                   ` Rui Salvaterra
2020-05-21  9:07                     ` Rui Salvaterra
2020-05-21 10:46                       ` Michael Büsch
2020-05-21 11:30                         ` Rui Salvaterra
2020-05-21 11:40                           ` Michael Büsch
2020-05-21 14:10                             ` Larry Finger
2020-05-21 14:52                             ` Rui Salvaterra
2020-05-21 16:17                               ` Rui Salvaterra
2020-05-21 18:59                                 ` Larry Finger
2020-05-21 19:19                                   ` Rui Salvaterra
2020-05-21 20:23                                     ` Rui Salvaterra
2020-05-21 21:47                                       ` Larry Finger
2020-05-22 10:19                                         ` Michael Büsch [this message]
2020-05-22 11:49                                           ` Kalle Valo
2020-05-22 13:46                                             ` Rui Salvaterra
2020-05-22 18:02                                               ` Larry Finger
2020-05-22 20:04                                                 ` Rui Salvaterra
2020-05-22 20:40                                                 ` Rui Salvaterra
2020-05-22 21:06                                                   ` Larry Finger
2020-05-23  0:35                                                     ` Rui Salvaterra
2020-05-23 21:17                                                     ` Rafał Miłecki
2020-05-25  6:56                                                       ` Kalle Valo
2020-05-22 17:15                                             ` Larry Finger

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=20200522121910.254aefc1@wiggum \
    --to=m@bues.ch \
    --cc=Larry.Finger@lwfinger.net \
    --cc=b43-dev@lists.infradead.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=rsalvaterra@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).