linux-kernel - Re: [PATCH 5/5] PCI: st: disable IO support

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: <20141217140131.607a1ac7@lxorguk.ukuu.org.uk>
Date:	Wed, 17 Dec 2014 14:01:31 +0000
From:	One Thousand Gnomes <gnomes@...rguk.ukuu.org.uk>
To:	Gabriel FERNANDEZ <gabriel.fernandez@...com>
Cc:	Rob Herring <robh+dt@...nel.org>, Pawel Moll <pawel.moll@....com>,
	Mark Rutland <mark.rutland@....com>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Kumar Gala <galak@...eaurora.org>,
	Srinivas Kandagatla <srinivas.kandagatla@...il.com>,
	Maxime Coquelin <maxime.coquelin@...com>,
	Patrice Chotard <patrice.chotard@...com>,
	Russell King <linux@....linux.org.uk>,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Mohit Kumar <mohit.kumar@...com>,
	Jingoo Han <jg1.han@...sung.com>,
	Grant Likely <grant.likely@...aro.org>,
	Gabriel Fernandez <gabriel.fernandez@...aro.org>,
	Fabrice Gasnier <fabrice.gasnier@...com>,
	Arnd Bergmann <arnd@...db.de>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	Thierry Reding <treding@...dia.com>,
	Minghuan Lian <Minghuan.Lian@...escale.com>,
	Magnus Damm <damm@...nsource.se>,
	Will Deacon <will.deacon@....com>,
	Tanmay Inamdar <tinamdar@....com>,
	Murali Karicheri <m-karicheri2@...com>,
	Kishon Vijay Abraham I <kishon@...com>,
	Pratyush Anand <pratyush.anand@...com>,
	Sachin Kamat <sachin.kamat@...sung.com>,
	Andrew Lunn <andrew@...n.ch>,
	Liviu Dudau <Liviu.Dudau@....com>,
	Srikanth Thokala <sthokal@...inx.com>,
	devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, kernel@...inux.com,
	linux-pci@...r.kernel.org, Lee Jones <lee.jones@...aro.org>
Subject: Re: [PATCH 5/5] PCI: st: disable IO support

On Wed, 17 Dec 2014 11:34:46 +0100
Gabriel FERNANDEZ <gabriel.fernandez@...com> wrote:

> sti SoCs PCIe IPs are built around DesignWare IP Core.
> But in these SoCs, PCIe IP doesn't support IO.
> By default, when no IO space is provided, a default one is assigned.
> 
> Add an empty IO resource to the bus, and disable IO by default.

As a point of PCI pedantry I don't think this is quite sufficient. PCI
has a weird corner case where I/O resources are implied rather than
allocated.

For IDE/SATA you may need to something like

	if (class == PCI_CLASS_STORAGE_IDE) {
		u8 progif;
		pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
		progif |= 5;
		pci_write_config_byte(dev, PCI_CLASS_PROG, &progif);
	}

so that any adapter is kicked out of legacy mode and doesn't get implied
I/O resources and interrupts. I don't know if that case matters for your
usage.


--
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/