linux-kernel - Re: Subject: [PATCH] x86/pci: Detect mmconfig on nVidia MCP55 -v2

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]

Message-ID: <9ae48b020902111400pa9bc287s12dbbb38bad9866d@mail.gmail.com>
Date:	Wed, 11 Feb 2009 14:00:35 -0800
From:	Ed Swierk <eswierk@...stanetworks.com>
To:	Yinghai Lu <yinghai@...nel.org>
Cc:	jbarnes@...tuousgeek.org, Ingo Molnar <mingo@...e.hu>,
	hpa@...or.com, linux-kernel@...r.kernel.org,
	linux-pci@...r.kernel.org
Subject: Re: Subject: [PATCH] x86/pci: Detect mmconfig on nVidia MCP55 -v2

On Tue, Feb 10, 2009 at 9:05 PM, Yinghai Lu <yinghai@...nel.org> wrote:
> try to make thing simple.
> for system: with AMD Fam10h, and MCP55 + 2 IO55
> amd fam10h cpu: said it needs [0,0]
> mcp55: said it need [0,255]
> io55 #1: said it need [0x40, 0x40+255], then u8 end_bus_number = 0x3f
> io55 #2: said it need [0x80, 0x80+255], then u8 end_bus_number = 0x7f
> MMIO route in NBs is right.

Oh, I misinterpreted your earlier comment--I thought you were
referring to 0x40, 0x80, 0xc0 as devfns, not bus numbers. The MCP55 is
on device 0 on our board as well.

> but MCFG is right... so just use that.
>
> when acpi=off, if check_and_enable_amd_mconf, it will forcely to make
> amd fam10h cpu: said it needs [0,255] and pci_mmcfg_config_num = 1
> so mcp55 mconf is not used.

OK, I'm just pointing out that the existing mmconfig hostbridge
detection code overrides ACPI MCFG. Past commit comments suggest that
the hostbridge registers are more trustworthy than ACPI on some
boards.

--Ed
--
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/