From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: irq_guest_eoi_timer interaction with MSI
Date: Tue, 25 Nov 2008 08:40:13 +0000
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	<C5516830.1F905%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>
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>>> Keir Fraser <keir.fraser@eu.citrix.com> 25.11.08 09:30 >>>
>On 25/11/08 08:15, "Jan Beulich" <jbeulich@novell.com> wrote:
>
>>> The fixmap stuff is a bit ugly and I would just have done a
>>> map_domain_page_global() for 32-bit Xen (good enough as far as I'm
>>> concerned). I'm not dead set against your approach if you like it very =
much,
>>> though.
>>=20
>> But just as map_domain_page(), map_domain_page_global() can't be used
>> out of IRQ context...
>
>I would have kept the page mapped from when it was registered until =
domain
>death. Same as we do for guest-registered vcpu_info.

Oh, I indeed didn't consider that option. The question is - does it scale?
2Mb doesn't seem all that much for a global pool, but otoh it's perhaps
unlikely that 32-bit hypervisors would have to manage too large an
amount of domains/vCPU-s. So yes, I'll go that route.

Jan