Re: [PATCH v4 3/3] memory_hotplug.c: send DEVICE_UNPLUG_ERROR in acpi_memory_hotplug_write()

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 08 Jul 2021 15:08:57 +0200
Markus Armbruster <armbru@redhat.com> wrote:

> Daniel Henrique Barboza <danielhb413@gmail.com> writes:
> 
> > MEM_UNPLUG_ERROR is deprecated since the introduction of
> > DEVICE_UNPLUG_ERROR. Keep emitting both while the deprecation of
> > MEM_UNPLUG_ERROR is pending.
> >
> > CC: Michael S. Tsirkin <mst@redhat.com>
> > CC: Igor Mammedov <imammedo@redhat.com>
> > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
> > ---
> >  hw/acpi/memory_hotplug.c | 13 +++++++++++--
> >  1 file changed, 11 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/acpi/memory_hotplug.c b/hw/acpi/memory_hotplug.c
> > index af37889423..fb9f4d2de7 100644
> > --- a/hw/acpi/memory_hotplug.c
> > +++ b/hw/acpi/memory_hotplug.c
> > @@ -8,6 +8,7 @@
> >  #include "qapi/error.h"
> >  #include "qapi/qapi-events-acpi.h"
> >  #include "qapi/qapi-events-machine.h"
> > +#include "qapi/qapi-events-qdev.h"
> >  
> >  #define MEMORY_SLOTS_NUMBER          "MDNR"
> >  #define MEMORY_HOTPLUG_IO_REGION     "HPMR"
> > @@ -177,9 +178,17 @@ static void acpi_memory_hotplug_write(void *opaque, hwaddr addr, uint64_t data,
> >              /* call pc-dimm unplug cb */
> >              hotplug_handler_unplug(hotplug_ctrl, dev, &local_err);
> >              if (local_err) {
> > +                const char *error_pretty = error_get_pretty(local_err);
> > +
> >                  trace_mhp_acpi_pc_dimm_delete_failed(mem_st->selector);
> > -                qapi_event_send_mem_unplug_error(dev->id,
> > -                                                 error_get_pretty(local_err));
> > +
> > +                /*
> > +                 * Send both MEM_UNPLUG_ERROR and DEVICE_UNPLUG_ERROR
> > +                 * while the deprecation of MEM_UNPLUG_ERROR is
> > +                 * pending.
> > +                 */
> > +                qapi_event_send_mem_unplug_error(dev->id, error_pretty);
> > +                qapi_event_send_device_unplug_error(dev->id, error_pretty);
> >                  error_free(local_err);
> >                  break;
> >              }  
> 
> Same question as for PATCH 2: can dev->id be null?
only theoretically (if memory device were created directly without
using device_add), which as far as I know is not the case as all
memory devices are created using -device/device_add so far.

( for device_add case see qdev_device_add->qdev_set_id where
  'id' is set to user provided or to generated "device[%d]" value)