From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: KVM: x86: update masterclock when kvmclock_offset is calculated
Date: Fri, 23 Aug 2013 12:00:46 +0200
Message-ID: <521732CE.9070309@redhat.com>
References: <20130820182012.GA814@amt.cnet> <521644D0.9050902@redhat.com>
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	kvm-devel <kvm@vger.kernel.org>, Gleb Natapov <gleb@redhat.com>
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Il 22/08/2013 19:05, Paolo Bonzini ha scritto:
> Il 20/08/2013 20:20, Marcelo Tosatti ha scritto:
>>
>> The offset to add to the hosts monotonic time, kvmclock_offset, is
>> calculated against the monotonic time at KVM_SET_CLOCK ioctl time.
>>
>> Request a master clock update at this time, to reduce a potentially
>> unbounded difference between the values of the masterclock and
>> the clock value used to calculate kvmclock_offset.
>>
>> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>>
>> Index: linux-2.6-kvmclock-fixes/arch/x86/kvm/x86.c
>> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> --- linux-2.6-kvmclock-fixes.orig/arch/x86/kvm/x86.c
>> +++ linux-2.6-kvmclock-fixes/arch/x86/kvm/x86.c
>> @@ -3806,6 +3806,7 @@ long kvm_arch_vm_ioctl(struct file *filp
>>  		delta =3D user_ns.clock - now_ns;
>>  		local_irq_enable();
>>  		kvm->arch.kvmclock_offset =3D delta;
>> +		kvm_gen_update_masterclock(kvm);
>>  		break;
>>  	}
>>  	case KVM_GET_CLOCK: {
>=20
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

Actually, what commit is this patch based on?  You are calling the=20
function at line 3799, but it is only declared at line 5786, and this=20
causes:

/root/kvm-kmod/x86/x86.c: In function =91kvm_arch_vm_ioctl=92:
/root/kvm-kmod/x86/x86.c:3799:3: error: implicit declaration of functio=
n =91kvm_gen_update_masterclock=92
/root/kvm-kmod/x86/x86.c: At top level:
/root/kvm-kmod/x86/x86.c:5786:13: warning: conflicting types for =91kvm=
_gen_update_masterclock=92
/root/kvm-kmod/x86/x86.c:5786:13: error: static declaration of =91kvm_g=
en_update_masterclock=92 follows non-static declaration
/root/kvm-kmod/x86/x86.c:3799:3: note: previous implicit declaration of=
 =91kvm_gen_update_masterclock=92 was here

Paolo