From: Boris Ostrovsky Date: Mon, 21 Sep 2015 13:09:28 +0000 (-0400) Subject: xen/x86: Don't try to write syscall-related MSRs for PV guests X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2ecf91b6d8b0ee8ef38aa7ea2a0fe0cd57b6ca50;p=linux-beck.git xen/x86: Don't try to write syscall-related MSRs for PV guests 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 Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: David Vrabel --- diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 30d12afe52ed..1f1dbd2949a4 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))