From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH] x86/HVM: Fixed the bug which cause the
 nested hvm guest fail to boot
Date: Mon, 18 Aug 2014 12:26:00 +0100
Message-ID: <53F1E2C8.3090506@citrix.com>
References: <1408360314-25784-1-git-send-email-liangx.z.li@intel.com>
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To: Liliang <liangx.z.li@intel.com>, xen-devel@lists.xen.org
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On 18/08/14 12:11, Liliang wrote:
> From: Li Liang <liangx.z.li@intel.com>
>
> The function memory_type_changed should not be called in hvm_set_guest_pat.
> or the cache will be flushed excessively and make the nested guest very slowly,
> just like blocked.
>
> Signed-off-by: Li Liang <liangx.z.li@intel.com>

Whyso?  Without it, the caching types are likely wrong, especially after
setting pat.

~Andrew

> ---
>  xen/arch/x86/hvm/hvm.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
> index d40c48e..1a0534b 100644
> --- a/xen/arch/x86/hvm/hvm.c
> +++ b/xen/arch/x86/hvm/hvm.c
> @@ -257,7 +257,6 @@ int hvm_set_guest_pat(struct vcpu *v, u64 guest_pat)
>      if ( !hvm_funcs.set_guest_pat(v, guest_pat) )
>          v->arch.hvm_vcpu.pat_cr = guest_pat;
>  
> -    memory_type_changed(v->domain);
>  
>      return 1;
>  }