From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Benjamin LaHaise <bcrl@kvack.org>
Cc: Vincent Sanders <vincent.sanders@collabora.co.uk>,
David Miller <davem@davemloft.net>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: AF_BUS socket address family
Date: Sat, 30 Jun 2012 13:52:40 +0100 [thread overview]
Message-ID: <20120630135240.41dbaacf@pyramind.ukuu.org.uk> (raw)
In-Reply-To: <20120630001350.GS21968@kvack.org>
On Fri, 29 Jun 2012 20:13:50 -0400
Benjamin LaHaise <bcrl@kvack.org> wrote:
> On Sat, Jun 30, 2012 at 12:42:30AM +0100, Vincent Sanders wrote:
> > The current users are suffering from the issues outlined in my
> > introductory mail all the time. These issues are caused by emulating an
> > IPC system over AF_UNIX in userspace.
>
> Nothing in your introductory statements indicate how your requirements
> can't be met through a hybrid socket + shared memory solution. The IPC
> facilities of the kernel are already quite rich, and sufficient for
> building many kinds of complex systems. What's so different about DBus'
> requirements?
dbus wants to
- multicast
- pass file handles
- never lose an event
- be fast
- have a security model
The security model makes a shared memory hack impractical, the file
handle passing means at least some of it needs to be AF_UNIX. The event
loss handling/speed argue for putting it in kernel.
I'm not convinced AF_BUS entirely sorts this either. In particular the
failure case dbus currently has to handle for not losing events allows it
to identify who in a "group" has jammed the bus by not listening (eg by
locking up). This information appears to be lost in the AF_BUS case and
that's slightly catastrophic for error recovery.
Alan
next prev parent reply other threads:[~2012-06-30 12:52 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-29 16:45 AF_BUS socket address family Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 01/15] net: bus: Add " Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 02/15] net: bus: Add documentation for AF_BUS Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 03/15] net: bus: Add AF_BUS socket and address definitions Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 04/15] security: Add Linux Security Modules hook for AF_BUS sockets Vincent Sanders
2012-07-09 3:32 ` James Morris
2012-07-09 18:02 ` Paul Moore
2012-06-29 16:45 ` [PATCH net-next 05/15] security: selinux: Add AF_BUS socket SELinux hooks Vincent Sanders
2012-07-09 18:38 ` Paul Moore
2012-06-29 16:45 ` [PATCH net-next 06/15] netfilter: Add NFPROTO_BUS hook constant for AF_BUS socket family Vincent Sanders
2012-07-01 2:15 ` Jan Engelhardt
2012-06-29 16:45 ` [PATCH net-next 07/15] scm: allow AF_BUS sockets to send ancillary data Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 08/15] net: bus: Add implementation of Bus domain sockets Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 09/15] net: bus: Add garbage collector for AF_BUS sockets Vincent Sanders
2012-07-02 17:44 ` Ben Hutchings
2012-07-03 12:11 ` Alban Crequy
2012-06-29 16:45 ` [PATCH net-next 10/15] net: bus: Add the AF_BUS socket address family to KBuild Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 11/15] netlink: connector: implement cn_netlink_reply Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 12/15] netlink: connector: Add idx and val identifiers for netfilter D-Bus Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 13/15] netfilter: nfdbus: Add D-bus message parsing Vincent Sanders
2012-06-29 17:11 ` Pablo Neira Ayuso
2012-07-02 15:43 ` Javier Martinez Canillas
2012-07-04 17:30 ` Pablo Neira Ayuso
2012-07-05 17:54 ` Javier Martinez Canillas
2012-06-29 16:45 ` [PATCH net-next 14/15] netfilter: nfdbus: Add D-bus match rule implementation Vincent Sanders
2012-06-29 16:45 ` [PATCH net-next 15/15] netfilter: add netfilter D-Bus module Vincent Sanders
2012-06-29 18:16 ` AF_BUS socket address family Chris Friesen
2012-06-29 19:33 ` Ben Hutchings
2012-06-29 18:45 ` Casey Schaufler
2012-06-29 23:22 ` Vincent Sanders
2012-06-29 22:36 ` David Miller
2012-06-29 23:12 ` Vincent Sanders
2012-06-29 23:18 ` David Miller
2012-06-29 23:42 ` Vincent Sanders
2012-06-29 23:50 ` David Miller
2012-06-30 0:09 ` Vincent Sanders
2012-06-30 13:12 ` Alan Cox
2012-07-01 0:33 ` David Miller
2012-07-01 14:16 ` Alan Cox
2012-07-01 21:45 ` David Miller
2012-06-30 0:13 ` Benjamin LaHaise
2012-06-30 12:52 ` Alan Cox [this message]
2012-07-02 14:51 ` Vincent Sanders
2012-07-02 4:49 ` Chris Friesen
2012-07-05 21:06 ` Jan Engelhardt
2012-07-06 18:27 ` Chris Friesen
2012-06-30 20:41 ` Hans-Peter Jansen
2012-07-02 16:46 ` Alban Crequy
2012-07-05 7:59 ` Linus Walleij
2012-07-05 16:01 ` Daniel Walker
-- strict thread matches above, loose matches on Subject: below --
2012-07-02 15:18 Javier Martinez Canillas
2012-07-03 16:52 ` Chris Friesen
2012-07-03 17:18 ` Chris Friesen
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