Re: [Qemu-devel] [PATCH 1/2] qem-xen: add later wakeup logic when qemu wakeup

[Stefano Stabellini]

On Tue, 3 Sep 2013, Liu, Jinsong wrote:
> Anthony PERARD wrote:
> > On 01/09/13 10:51, Liu, Jinsong wrote:
> >> From 86ad3bb83a984ad7bbc00b81d6a0bfc1abc543ca Mon Sep 17 00:00:00
> >> 2001 
> >> From: Liu Jinsong <address@hidden>
> >> Date: Sun, 1 Sep 2013 23:39:14 +0800
> >> Subject: [PATCH 1/2] qemu-xen: add later wakeup logic when qemu
> >> wakeup 
> >> 
> >> Currently HVM S3 has a bug coming from the difference between
> >> qemu-traditioanl and qemu-xen. For qemu-traditional, the way
> >> to resume from hvm s3 is via 'xl trigger' command. However,
> >> for qemu-xen, the way to resume from hvm s3 inherited from
> >> standard qemu, i.e. via QMP, and it doesn't work under Xen.
> >> 
> >> The root cause is, for qemu-xen, 'xl trigger' command didn't reset
> >> devices, while QMP didn't unpause hvm domain though they did qemu
> >> system reset.
> >> 
> >> We have two qemu-xen patches and one xl patch to fix the HVM S3 bug.
> >> This patch is the qemu-xen patch 1. It provides a later wakeup
> >> notifier 
> >> and a register function, and notifies the later wakeup list when
> >> qemu wakup by 'xl trigger' command.
> >> 
> >> Signed-off-by: Liu Jinsong <address@hidden>
> >> ---
> >>  sysemu.h |    1 +
> >>  vl.c     |    8 ++++++++
> >>  2 files changed, 9 insertions(+), 0 deletions(-)
> >> 
> >> diff --git a/sysemu.h b/sysemu.h
> >> index b71f244..4dbcab7 100644
> >> --- a/sysemu.h
> >> +++ b/sysemu.h
> >> @@ -49,6 +49,7 @@ void qemu_register_suspend_notifier(Notifier
> >>  *notifier); void qemu_system_wakeup_request(WakeupReason reason);
> >>  void qemu_system_wakeup_enable(WakeupReason reason, bool enabled);
> >>  void qemu_register_wakeup_notifier(Notifier *notifier);
> >> +void qemu_register_later_wakeup_notifier(Notifier *notifier);
> >>  void qemu_system_shutdown_request(void);
> >>  void qemu_system_powerdown_request(void);
> >>  void qemu_register_powerdown_notifier(Notifier *notifier);
> >> diff --git a/vl.c b/vl.c
> >> index 5314f55..1c4842d 100644
> >> --- a/vl.c
> >> +++ b/vl.c
> >> @@ -1478,6 +1478,8 @@ static NotifierList suspend_notifiers =
> >>      NOTIFIER_LIST_INITIALIZER(suspend_notifiers);
> >>  static NotifierList wakeup_notifiers =
> >>      NOTIFIER_LIST_INITIALIZER(wakeup_notifiers);
> >> +static NotifierList later_wakeup_notifiers =
> >> +    NOTIFIER_LIST_INITIALIZER(later_wakeup_notifiers);
> >>  static uint32_t wakeup_reason_mask = ~0;
> >>  static RunState vmstop_requested = RUN_STATE_MAX;
> >> 
> >> @@ -1668,6 +1670,11 @@ void qemu_register_wakeup_notifier(Notifier
> >>      *notifier) notifier_list_add(&wakeup_notifiers, notifier);  }
> >> 
> >> +void qemu_register_later_wakeup_notifier(Notifier *notifier) +{
> >> +    notifier_list_add(&later_wakeup_notifiers, notifier); +}
> >> +
> >>  void qemu_system_killed(int signal, pid_t pid)
> >>  {
> >>      shutdown_signal = signal;
> >> @@ -1744,6 +1751,7 @@ static bool main_loop_should_exit(void)
> >>          cpu_synchronize_all_states();
> >>          qemu_system_reset(VMRESET_SILENT);
> >>          resume_all_vcpus();
> >> +        notifier_list_notify(&later_wakeup_notifiers, NULL);
> >>          monitor_protocol_event(QEVENT_WAKEUP, NULL);      }
> >>      if (qemu_powerdown_requested()) {
> >> 
> > 
> > The patch those not apply properly to QEMU (upstream) but it just
> > because the file sysemu.h have been moved to include/sysemu/sysemu.h
> > 
> > Once this is fix:
> > Acked-by: Anthony PERARD <address@hidden>
> 
> Yes. The patches are for qemu-xen tree, to fix xen hvm s3 issue.
> 
> Where should the 2 patches be checked in? qemu upstream (then backport to 
> qemu-xen tree), or, qemu-xen tree?

In general patches should go to qemu upstream first and then
be backported to qemu-xen.