linux-kernel - Re: arch/x86/Kconfig selects invalid HAVE_READQ, HAVE

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

Date:	Sun, 19 Apr 2009 20:08:52 -0600
From:	Robert Hancock <hancockrwd@...il.com>
To:	Roland Dreier <rdreier@...co.com>
CC:	Ingo Molnar <mingo@...e.hu>, "H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	"Robert P. J. Day" <rpjday@...shcourse.ca>,
	Hitoshi Mitake <h.mitake@...il.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: arch/x86/Kconfig selects invalid HAVE_READQ, HAVE_WRITEQ vars

Roland Dreier wrote:
>  > Also, atomicity might not be possible to guarantee on the bus level: 
>  > say the device sits on a 32-bit PCI bus. (No matter what instruction 
>  > the CPU gets, a readq/writeq there has to be done as two 32-bit bus 
>  > accesses.)
> 
> Well, the conventional PCI devices I know of with 64-bit registers were
> PCI-X cards, keyed so they would only fit into a 64-bit slot.  And of
> course there is no such thing as 32-bit PCI Express.

It's quite possible to use most 64-bit PCI-X cards in a 32-bit slot, 
with the 64-bit part of the card not plugged into anything. It's 
supposed to work (as long as the card can handle the voltage the slot uses).
--
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/