linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Johannes Berg <johannes@sipsolutions.net>
To: Takashi Iwai <tiwai@suse.de>
Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>,
	linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: systemd-rfkill regression on 5.11 and later kernels
Date: Fri, 19 Mar 2021 23:15:14 +0100	[thread overview]
Message-ID: <14f7bbfea8a17dcd12e7d40641198063428d19b3.camel@sipsolutions.net> (raw)
In-Reply-To: <9db9d9ae751a50c9fd1da1ee3bd4c564546ce1c5.camel@sipsolutions.net> (sfid-20210318_121746_242488_98446BA5)

On Thu, 2021-03-18 at 12:16 +0100, Johannes Berg wrote:
> > Yeah, that's a dilemma.  An oft-seen trick is to add more bytes for
> > the future use, e.g. extend to 16 bytes and fill 0 for the remaining.
> 
> Yeah, I guess I could stick a reserved[15] there, it's small enough.

Actually, that doesn't really help anything either.

If today I require that the reserved bytes are sent as 0 by userspace,
then any potential expansion that requires userspace to set it will
break when userspace does it and runs on an old kernel.

If I don't require the reserved bytes to be set to 0 then somebody will
invariably get it wrong and send garbage, and then we again cannot
extend it.

So ... that all seems pointless. I guess I'll send the patch as it is
now.

johannes


      reply	other threads:[~2021-03-19 22:15 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-18  8:27 systemd-rfkill regression on 5.11 and later kernels Takashi Iwai
2021-03-18  9:26 ` Emmanuel Grumbach
2021-03-18  9:36 ` Johannes Berg
2021-03-18 10:07   ` Takashi Iwai
2021-03-18 10:50     ` Johannes Berg
2021-03-18 11:11       ` Takashi Iwai
2021-03-18 11:16         ` Johannes Berg
2021-03-19 22:15           ` Johannes Berg [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=14f7bbfea8a17dcd12e7d40641198063428d19b3.camel@sipsolutions.net \
    --to=johannes@sipsolutions.net \
    --cc=emmanuel.grumbach@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=tiwai@suse.de \
    /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).