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Date: Fri, 31 Jul 2015 10:41:07 +0100
From: David Vrabel <david.vrabel@citrix.com>
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To: Andy Lutomirski <luto@kernel.org>, X86 ML <x86@kernel.org>,
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	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: [Xen-devel] [PATCH v6 1/4] x86/xen: Probe target addresses in
 set_aliased_prot before the hypercall
References: <cover.1438291540.git.luto@kernel.org>
 <0b0e55b995cda11e7829f140b833ef932fcabe3a.1438291540.git.luto@kernel.org>
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On 30/07/15 22:31, Andy Lutomirski wrote:
> The update_va_mapping hypercall can fail if the VA isn't present in
> the guest's page tables.  Under certain loads, this can result in an
> OOPS when the target address is in unpopulated vmap space.
> 
> While we're at it, add comments to help explain what's going on.
> 
> This isn't a great long-term fix.  This code should probably be
> changed to use something like set_memory_ro.

Reviewed-by: David Vrabel <david.vrabel@citrix.com>

Thanks.

David