From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] remove static declaration from wall clock version
Date: Thu, 26 Feb 2009 20:50:26 +0100
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To: Glauber Costa <glommer@redhat.com>
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On Thursday 26 February 2009, Glauber Costa wrote:
> @@ -548,15 +548,13 @@ static int do_set_msr(struct kvm_vcpu *vcpu, un=
signed index, u64 *data)
> =A0
> =A0static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock=
)
> =A0{
> -=A0=A0=A0=A0=A0=A0=A0static int version;
> +=A0=A0=A0=A0=A0=A0=A0int version =3D 1;
> =A0=A0=A0=A0=A0=A0=A0=A0struct pvclock_wall_clock wc;
> =A0=A0=A0=A0=A0=A0=A0=A0struct timespec now, sys, boot;
> =A0
> =A0=A0=A0=A0=A0=A0=A0=A0if (!wall_clock)
> =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0return;
> =A0
> -=A0=A0=A0=A0=A0=A0=A0version++;
> -
> =A0=A0=A0=A0=A0=A0=A0=A0kvm_write_guest(kvm, wall_clock, &version, si=
zeof(version));
> =A0
> =A0=A0=A0=A0=A0=A0=A0=A0/*

Doesn't this mean that kvm_write_guest now writes an uninitialized valu=
e
to the guest?

I think what you need here is a 'static atomic_t version;' so you can
do an atomic_inc instead of the ++.

	Arnd <><