From c5941bc786984acdd0a6a354b6182f6887d40391 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti <mtosatti@redhat.com> Date: Fri, 29 Jan 2010 19:43:09 -0200 Subject: [PATCH] KVM: PIT: control word is write-only RH-Author: Marcelo Tosatti <mtosatti@redhat.com> Message-id: <20100129194309.GB17352@amt.cnet> Patchwork-id: 6799 O-Subject: [RHEL 5.5 5.4.z] KVM: PIT: control word is write-only Bugzilla: 553126 RH-Acked-by: Glauber Costa <glommer@redhat.com> RH-Acked-by: Gleb Natapov <gleb@redhat.com> RH-Acked-by: Juan Quintela <quintela@redhat.com> PIT control word (address 0x43) is write-only, reads are undefined. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Bugzilla: 553126 Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> --- arch/x86/kvm/i8254.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 7fc515d..4cc536a 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -419,6 +419,9 @@ static void pit_ioport_read(struct kvm_io_device *this, struct kvm_kpit_channel_state *s; addr &= KVM_PIT_CHANNEL_MASK; + if (addr == 3) + return; + s = &pit_state->channels[addr]; mutex_lock(&pit_state->lock); -- 1.6.3.rc4.29.g8146