linux-kernel - Re: [PATCH v8 1/4] firmware: introduce sysfs driver for QEMU's fw

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: <20160221151050-mutt-send-email-mst@redhat.com>
Date:	Sun, 21 Feb 2016 15:14:00 +0200
From:	"Michael S. Tsirkin" <mst@...hat.com>
To:	"Gabriel L. Somlo" <somlo@....edu>
Cc:	gregkh@...uxfoundation.org, robh+dt@...nel.org, pawel.moll@....com,
	mark.rutland@....com, ijc+devicetree@...lion.org.uk,
	galak@...eaurora.org, arnd@...db.de, lersek@...hat.com,
	ralf@...ux-mips.org, rmk+kernel@....linux.org.uk, eric@...olt.net,
	hanjun.guo@...aro.org, zajec5@...il.com, sudeep.holla@....com,
	agross@...eaurora.org, linux-api@...r.kernel.org,
	linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
	qemu-devel@...gnu.org, imammedo@...hat.com,
	peter.maydell@...aro.org, leif.lindholm@...aro.org,
	ard.biesheuvel@...aro.org, pbonzini@...hat.com, kraxel@...hat.com,
	ehabkost@...hat.com, luto@...capital.net, stefanha@...il.com,
	revol@...e.fr, matt@...eblueprint.co.uk, rth@...ddle.net
Subject: Re: [PATCH v8 1/4] firmware: introduce sysfs driver for QEMU's
 fw_cfg device

On Sun, Feb 21, 2016 at 08:06:17AM -0500, Gabriel L. Somlo wrote:
> > So for all arches which support ACPI, I think this driver
> > should just rely on ACPI.
> 
> There was a discussion about that a few versions ago, and IIRC the
> conclusion was not to expect the firmware to contend for fw_cfg access
> after the guest kernel boots:
> 
> https://lkml.org/lkml/2015/10/5/283

Interesting. Igor wanted to do this again recently ...
I'll think it over and get back to you/list on this.

> (I even had a prototype version doing what you suggested, but per the above
> reference decided to drop it -- which IMHO is for the better, since otherwise
> I'd have had to ifdef between ACPI and non-ACPI versions of the driver --
> see https://lkml.org/lkml/2015/11/4/534 )

I'm not sure I get it - won't you only ifdef the accessor function?

-- 
MST