| Message ID | 1470735603-13511-1-git-send-email-rcojocaru@bitdefender.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 08/09/2016 12:40 PM, Razvan Cojocaru wrote: > Vm_event_vcpu_pause() needs to use vcpu_pause_nosync() in order > for the current vCPU to not get stuck. A consequence of this is > that the custom vm_event response handlers will not always see > the real vCPU state in v->arch.user_regs. This patch makes sure > that the state is always synchronized in vm_event_resume, before > any handlers have been called. This problem especially affects > vm_event_set_registers(). > > Signed-off-by: Razvan Cojocaru <rcojocaru@bitdefender.com> > --- > xen/common/vm_event.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/xen/common/vm_event.c b/xen/common/vm_event.c > index 941345b..22cafd4 100644 > --- a/xen/common/vm_event.c > +++ b/xen/common/vm_event.c > @@ -388,6 +388,12 @@ void vm_event_resume(struct domain *d, struct vm_event_domain *ved) > v = d->vcpu[rsp.vcpu_id]; > > /* > + * Make sure the vCPU state has been synchronized for the custom > + * handlers. > + */ > + sync_vcpu_execstate(v); > + > + /* > * In some cases the response type needs extra handling, so here > * we call the appropriate handlers. > */ > Actually, reading the email Tim has sent in the meantime, I should only call sync_vcpu_execstate() if I know for sure that the vCPU is paused. My tests have passed because all the events I subscribed to were requiring the vCPU to be paused, but obviously that's not always the case. Will wait for more input, then submit V2. Thanks, Razvan
diff --git a/xen/common/vm_event.c b/xen/common/vm_event.c index 941345b..22cafd4 100644 --- a/xen/common/vm_event.c +++ b/xen/common/vm_event.c @@ -388,6 +388,12 @@ void vm_event_resume(struct domain *d, struct vm_event_domain *ved) v = d->vcpu[rsp.vcpu_id]; /* + * Make sure the vCPU state has been synchronized for the custom + * handlers. + */ + sync_vcpu_execstate(v); + + /* * In some cases the response type needs extra handling, so here * we call the appropriate handlers. */
Vm_event_vcpu_pause() needs to use vcpu_pause_nosync() in order for the current vCPU to not get stuck. A consequence of this is that the custom vm_event response handlers will not always see the real vCPU state in v->arch.user_regs. This patch makes sure that the state is always synchronized in vm_event_resume, before any handlers have been called. This problem especially affects vm_event_set_registers(). Signed-off-by: Razvan Cojocaru <rcojocaru@bitdefender.com> --- xen/common/vm_event.c | 6 ++++++ 1 file changed, 6 insertions(+)