linux-kernel - Re: [PATCH] PCI: Always set prefetchable base/limit upper32 registers

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:	Mon, 30 Nov 2009 16:58:38 -0700
From:	Grant Grundler <grundler@...isc-linux.org>
To:	Yinghai Lu <yinghai@...nel.org>
Cc:	Alex Williamson <alex.williamson@...com>, jbarnes@...tuousgeek.org,
	linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] PCI: Always set prefetchable base/limit upper32
	registers

On Mon, Nov 30, 2009 at 01:52:03PM -0800, Yinghai Lu wrote:
> if HW state that reg is only 32bit pref,
> why should we care about the upper 32bit?

pref_mem64 describes the resource, not the HW.

All the PCI specs define Type 1 configuration space with Prefetchable Memory
register as 64-bit. Even if the Type 1 (PCI Bridge) HW ignores this register.
See "7.5.3. Type 1 Configuration Space Header" of PCI EXPRESS BASE
SPECIFICATION, REV. 1.1.

> looks like that your bridge device need quirk to clear that so called
> upper 32bit for it.

Hrm...I don't think this is a quirk. PCI spec defines 64-bit PrefMem
window register regardless of what type of resource we program into it.

hth,
grant
--
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/