From: Roger Pau Monné Date: Mon, 17 Jun 2013 09:12:41 +0000 (+0200) Subject: x86/vtsc: update vcpu_time in hvm_set_guest_time X-Git-Tag: 4.1.6-rc1~18 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=8b94e436ed3f83e899f5b0cc403461f95750964b;p=xen.git x86/vtsc: update vcpu_time in hvm_set_guest_time 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 master commit: 32c864a35ece2c24a336d183869a546798a4b241 master date: 2013-06-05 10:03:08 +0200 --- diff --git a/xen/arch/x86/hvm/vpt.c b/xen/arch/x86/hvm/vpt.c index 7056769ea3..52fb086876 100644 --- a/xen/arch/x86/hvm/vpt.c +++ b/xen/arch/x86/hvm/vpt.c @@ -56,7 +56,19 @@ 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)