linux-kernel - Re: Userspace I/O driver core

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20061216144813.GA29028@gallifrey>
Date:	Sat, 16 Dec 2006 14:48:13 +0000
From:	"Dr. David Alan Gilbert" <linux@...blig.org>
To:	Arjan van de Ven <arjan@...radead.org>
Cc:	Avi Kivity <avi@...o.co.il>, Greg KH <greg@...ah.com>,
	linux-kernel@...r.kernel.org, tglx@...utronix.de
Subject: Re: Userspace I/O driver core

* Arjan van de Ven (arjan@...radead.org) wrote:
> 
> > I understand one still has to write a kernel driver to shut up the irq.  
> > How about writing a small bytecode interpreter to make event than 
> > unnecessary?
> 
> if you do that why not do a real driver.

Because perhaps it is potentially very simple - i.e.
if most of these drivers turn out to be:

if (*loc1 & mask)
{
   *loc2=value;
   flag we have an interrupt
}

then all you actually need to do is provide a way to
specify loc1, mask, loc2 and value.  You could provide
a small handful of mechanisms to suit most simple pieces of hardware
and also provide a definition for the hardware designers to say
'if you make your interrupt registers like this then the software
is dead easy'.  A bytecode interpreter seems a little overkill
unless you think that two or three levels of that type of test/mask
could cope with 90%+ of the cases.
There are probably lots of people reinventing the wheel for simple IO 
boards and the hardware guys will be making it up each time as well.

Dave
-- 
 -----Open up your eyes, open up your mind, open up your code -------   
/ Dr. David Alan Gilbert    | Running GNU/Linux on Alpha,68K| Happy  \ 
\ gro.gilbert @ treblig.org | MIPS,x86,ARM,SPARC,PPC & HPPA | In Hex /
 \ _________________________|_____ http://www.treblig.org   |_______/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/