netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ben Hutchings <bhutchings@solarflare.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Jeff Garzik <jgarzik@pobox.com>, <netdev@vger.kernel.org>,
	David Miller <davem@davemloft.net>
Subject: Re: [PATCH] CONFIG_TR/CONFIG_LLC: work around the problem with select
Date: Mon, 6 Feb 2012 13:51:50 +0000	[thread overview]
Message-ID: <1328536310.2751.11.camel@bwh-desktop> (raw)
In-Reply-To: <20120205063139.GB23916@ZenIV.linux.org.uk>

On Sun, 2012-02-05 at 06:31 +0000, Al Viro wrote:
> As it is, with PCI/ISA/MCA/CCW all set to n and PCMCIA set to m
> setting TR to y will set LLC to m, with very unpleasant results -
> net/802/psnap gets picked into obj-y, resulting in the kernel
> that won't link - psnap calls functions from llc.  The cause,
> AFAICS, is that kconfig gets rev_dep for LLC containing
> || TR && (deps for TR)
> and even though TR is boolean, both LLC and PCMCIA are tristate
> and that thing becomes || y && (n || m), i.e. || m.  The reason
> for dependency on PCMCIA is that when none of PCI, ISA, MCA, CCW
> or PCMCIA is set there'll be no tokenring drivers, so there's no
> point building tokenring core.  Proper fix probably belongs in
> kconfig (we need strict and, such that y <strict_and> m would be
> y, so that rev_deps added for tristate selected by bool would
> use that instead of &&; we'd have || TR <strict_and> (deps for TR)
> in this case), but it's a rather intrusive change.  There's an
> easy workaround in case of TR -> LLC select, namely to have a def_bool y
> symbol sitting under if TR and have that symbol selecting LLC.
> Kudos to johill for suggesting that one...
[...]

This is pretty subtle; maybe it warrants a comment above WANT_LLC?

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

  reply	other threads:[~2012-02-06 13:51 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-05  6:31 [PATCH] CONFIG_TR/CONFIG_LLC: work around the problem with select Al Viro
2012-02-06 13:51 ` Ben Hutchings [this message]
2012-02-07 18:06 ` David Miller

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=1328536310.2751.11.camel@bwh-desktop \
    --to=bhutchings@solarflare.com \
    --cc=davem@davemloft.net \
    --cc=jgarzik@pobox.com \
    --cc=netdev@vger.kernel.org \
    --cc=viro@ZenIV.linux.org.uk \
    /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).