From eb60be3dd870aecfa47bed1118069680389c15f7 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 11 Apr 2013 12:07:55 +0200 Subject: [PATCH] x86: don't pass negative time to gtime_to_gtsc() scale_delta(), which is being called by that function, doesn't cope with that. Also print a warning message, so hopefully we can eventually figure why occasionally a negative value results from the calculation in the first place. Signed-off-by: Jan Beulich Acked-by: Keir Fraser --- xen/arch/x86/time.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c index b403f4711e..6e94847a49 100644 --- a/xen/arch/x86/time.c +++ b/xen/arch/x86/time.c @@ -854,7 +854,16 @@ static void __update_vcpu_system_time(struct vcpu *v, int force) if ( is_hvm_domain(d) ) { struct pl_time *pl = &v->domain->arch.hvm_domain.pl_time; + stime += pl->stime_offset + v->arch.hvm_vcpu.stime_offset; + if ( (s64)stime < 0 ) + { + printk(XENLOG_G_WARNING "d%dv%d: bogus time %" PRId64 + " (offsets %" PRId64 "/%" PRId64 ")\n", + d->domain_id, v->vcpu_id, stime, + pl->stime_offset, v->arch.hvm_vcpu.stime_offset); + stime = 0; + } } tsc_stamp = gtime_to_gtsc(d, stime); } -- 2.39.5