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Date: Mon, 25 Oct 2010 18:58:03 +0200
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 1/2] Keep track of ISA ports ISA device is
	using in qdev.
Message-ID: <20101025165803.GB31633@redhat.com>
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To: Markus Armbruster <armbru@redhat.com>
Cc: qemu-devel@nongnu.org

On Mon, Oct 25, 2010 at 05:06:51PM +0200, Markus Armbruster wrote:
> Gleb Natapov <gleb@redhat.com> writes:
> 
> > Prevent two devices from claiming the same io port.
> 
> Really?
> 
> Your new check for double-claim is in the new isa_init_ioport(), which
> is for ISADevice only.  Thus, only qdevified ISA devices can opt for
> this protection, by calling isa_init_ioport().  It doesn't protect from
> devices who don't or can't opt in, such as PCI devices.
> 
I didn't claim different. This obviously works only for ISA qdev
devices.

> Anyway, we already check for double-claim in
> register_ioport_{read,write}().  The check has issues --- hw_error() is
> wrong there for hot plug.  But it's where the check should be, isn't it?
You don't like double-claim checking? Forget about it (all 3 lines
of code). The real point of the patch is to have ISA resources used
by devices to be stored in common place (ISADevice) which allows
get_dev_path() to be implemented.

--
			Gleb.