linux-kernel - Re: [PATCH v7 03/60] sparc/PCI: Unify pci_register

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: <1445485662.2935.17.camel@kernel.crashing.org>
Date:	Thu, 22 Oct 2015 14:47:42 +1100
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	David Miller <davem@...emloft.net>, yinghai@...nel.org
Cc:	helgaas@...nel.org, bhelgaas@...gle.com,
	weiyang@...ux.vnet.ibm.com, linux@....tj, wangyijing@...wei.com,
	khalid.aziz@...cle.com, linux-pci@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v7 03/60] sparc/PCI: Unify pci_register_region()

On Wed, 2015-10-21 at 18:27 -0700, David Miller wrote:
> From: Yinghai Lu <yinghai@...nel.org>
> Date: Wed, 21 Oct 2015 11:16:53 -0700
> 
> > otherwise we need to compare res with pbm->mem_space or pbm
> ->mem64_space
> > to get direct parent for request_resource_conflict() calling in
> > pci_register_legacy_regions().
> 
> Right, this is the issue.
> 
> On sparc64, the cpu physical base address used for accessing 64-bit
> and non-64-bit memory spaces is different.
> 
> And that's why the resource values will be different.

This is the same on power btw, we have separate PowerBus windows to the
PHB that get mapped respectively to 32-bit PCI MMIO and 64-bit PCI
MMIO. The former gets "remapped" to generates 0-based PCI cycles, while
the latter is 1:1. So the offset between CPU and PCI changes depending
on which window you hit.

Cheers,
Ben.

--
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/