Re: [PATCH v3 04/12] Add "handle page fault" PV helper.

From: H. Peter Anvin
Date: Mon Jan 18 2010 - 03:38:24 EST


On 01/17/2010 06:44 AM, Gleb Natapov wrote:
On Thu, Jan 14, 2010 at 06:31:07PM +0100, Peter Zijlstra wrote:
On Tue, 2010-01-05 at 16:12 +0200, Gleb Natapov wrote:
Allow paravirtualized guest to do special handling for some page faults.

The patch adds one 'if' to do_page_fault() function. The call is patched
out when running on physical HW. I ran kernbech on the kernel with and
without that additional 'if' and result were rawly the same:

So why not program a different handler address for the #PF/#GP faults
and avoid the if all together?
I would gladly use fault vector reserved by x86 architecture, but I am
not sure Intel will be happy about it.


That's what it's there for... see Peter Z.'s response.

-hpa
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