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* [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests
@ 2015-09-21 13:09 Boris Ostrovsky
  2015-09-21 15:30 ` Konrad Rzeszutek Wilk
  2015-09-28 13:24 ` [Xen-devel] " David Vrabel
  0 siblings, 2 replies; 3+ messages in thread
From: Boris Ostrovsky @ 2015-09-21 13:09 UTC (permalink / raw)
  To: konrad.wilk, david.vrabel; +Cc: xen-devel, linux-kernel, boris.ostrovsky

For PV guests these registers are set up by hypervisor and thus
should not be written by the guest. The comment in xen_write_msr_safe()
says so but we still write the MSRs, causing the hypervisor to
print a warning.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
 arch/x86/xen/enlighten.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 30d12af..1f1dbd2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1077,6 +1077,7 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 		/* Fast syscall setup is all done in hypercalls, so
 		   these are all ignored.  Stub them out here to stop
 		   Xen console noise. */
+		break;
 
 	default:
 		if (!pmu_msr_write(msr, low, high, &ret))
-- 
2.1.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests
  2015-09-21 13:09 [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests Boris Ostrovsky
@ 2015-09-21 15:30 ` Konrad Rzeszutek Wilk
  2015-09-28 13:24 ` [Xen-devel] " David Vrabel
  1 sibling, 0 replies; 3+ messages in thread
From: Konrad Rzeszutek Wilk @ 2015-09-21 15:30 UTC (permalink / raw)
  To: Boris Ostrovsky; +Cc: david.vrabel, xen-devel, linux-kernel

On Mon, Sep 21, 2015 at 09:09:28AM -0400, Boris Ostrovsky wrote:
> For PV guests these registers are set up by hypervisor and thus
> should not be written by the guest. The comment in xen_write_msr_safe()
> says so but we still write the MSRs, causing the hypervisor to
> print a warning.
> 
> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

> ---
>  arch/x86/xen/enlighten.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
> index 30d12af..1f1dbd2 100644
> --- a/arch/x86/xen/enlighten.c
> +++ b/arch/x86/xen/enlighten.c
> @@ -1077,6 +1077,7 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
>  		/* Fast syscall setup is all done in hypercalls, so
>  		   these are all ignored.  Stub them out here to stop
>  		   Xen console noise. */
> +		break;
>  
>  	default:
>  		if (!pmu_msr_write(msr, low, high, &ret))
> -- 
> 2.1.0
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [Xen-devel] [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests
  2015-09-21 13:09 [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests Boris Ostrovsky
  2015-09-21 15:30 ` Konrad Rzeszutek Wilk
@ 2015-09-28 13:24 ` David Vrabel
  1 sibling, 0 replies; 3+ messages in thread
From: David Vrabel @ 2015-09-28 13:24 UTC (permalink / raw)
  To: Boris Ostrovsky, konrad.wilk, david.vrabel; +Cc: xen-devel, linux-kernel

On 21/09/15 14:09, Boris Ostrovsky wrote:
> For PV guests these registers are set up by hypervisor and thus
> should not be written by the guest. The comment in xen_write_msr_safe()
> says so but we still write the MSRs, causing the hypervisor to
> print a warning.

Applied to for-linus-4.3, thanks.

David

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2015-09-28 13:24 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2015-09-21 13:09 [PATCH] xen/x86: Don't try to write syscall-related MSRs for PV guests Boris Ostrovsky
2015-09-21 15:30 ` Konrad Rzeszutek Wilk
2015-09-28 13:24 ` [Xen-devel] " David Vrabel

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