From 32c864a35ece2c24a336d183869a546798a4b241 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Roger=20Pau=20Monn=C3=A9?= Date: Wed, 5 Jun 2013 10:03:08 +0200 Subject: [PATCH] x86/vtsc: update vcpu_time in hvm_set_guest_time MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When using a vtsc, hvm_set_guest_time changes hvm_vcpu.stime_offset, which is used in the vcpu time structure to calculate the tsc_timestamp, so after updating stime_offset we need to propagate the change to vcpu_time in order for the guest to get the right time if using the PV clock. Signed-off-by: Roger Pau Monné Reviewed-by: George Dunlap --- xen/arch/x86/hvm/vpt.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/hvm/vpt.c b/xen/arch/x86/hvm/vpt.c index 8dee662130..1961bda6a3 100644 --- a/xen/arch/x86/hvm/vpt.c +++ b/xen/arch/x86/hvm/vpt.c @@ -57,7 +57,19 @@ u64 hvm_get_guest_time(struct vcpu *v) void hvm_set_guest_time(struct vcpu *v, u64 guest_time) { - v->arch.hvm_vcpu.stime_offset += guest_time - hvm_get_guest_time(v); + u64 offset = guest_time - hvm_get_guest_time(v); + + if ( offset ) + { + v->arch.hvm_vcpu.stime_offset += offset; + /* + * If hvm_vcpu.stime_offset is updated make sure to + * also update vcpu time, since this value is used to + * calculate the TSC. + */ + if ( v == current ) + update_vcpu_system_time(v); + } } static int pt_irq_vector(struct periodic_time *pt, enum hvm_intsrc src) -- 2.30.2