Re: [RFC PATCH v2 09/16] hw/core/machine: Remove the dynamic sysbus devices type check

From: Alistair Francis <alistair23@gmail.com>
To: Damien Hedde <damien.hedde@greensocs.com>
Cc: "qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>,
	"Peter Maydell" <peter.maydell@linaro.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	"David Hildenbrand" <david@redhat.com>,
	"Peter Xu" <peterx@redhat.com>,
	mirela.grujic@greensocs.com,
	"Alistair Francis" <Alistair.Francis@wdc.com>,
	"Gerd Hoffmann" <kraxel@redhat.com>,
	"Ani Sinha" <ani@anisinha.ca>, "Eric Blake" <eblake@redhat.com>,
	"Stefano Stabellini" <sstabellini@kernel.org>,
	"open list:X86" <xen-devel@lists.xenproject.org>,
	"Paul Durrant" <paul@xen.org>,
	"Markus Armbruster" <armbru@redhat.com>,
	"Anthony Perard" <anthony.perard@citrix.com>,
	"Marc-André Lureau" <marcandre.lureau@redhat.com>,
	"Eduardo Habkost" <ehabkost@redhat.com>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	"Eric Auger" <eric.auger@redhat.com>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"open list:RISC-V" <qemu-riscv@nongnu.org>,
	"Daniel P. Berrangé" <berrange@redhat.com>,
	"Mark Burton" <mark.burton@greensocs.com>,
	"Edgar Iglesias" <edgari@xilinx.com>,
	"Igor Mammedov" <imammedo@redhat.com>
Subject: Re: [RFC PATCH v2 09/16] hw/core/machine: Remove the dynamic sysbus devices type check
Date: Wed, 13 Oct 2021 09:07:37 +1000	[thread overview]
Message-ID: <CAKmqyKNeUz7BTxhJTKnhTnEnONRJLJ8V-CaCZ3E5OA2G8eeP4A@mail.gmail.com> (raw)
In-Reply-To: <20210922161405.140018-10-damien.hedde@greensocs.com>

On Thu, Sep 23, 2021 at 2:23 AM Damien Hedde <damien.hedde@greensocs.com> wrote:
>
> Now that we check sysbus device types during device creation, we
> can remove the check done in the machine init done notifier.
> This was the only thing done by this notifier, so we remove the
> whole sysbus_notifier structure of the MachineState.
>
> Note: This notifier was checking all /peripheral and /peripheral-anon
> sysbus devices. Now we only check those added by -device cli option or
> device_add qmp command when handling the command/option. So if there
> are some devices added in one of these containers manually (eg in
> machine C code), these will not be checked anymore.
> This use case does not seem to appear apart from
> hw/xen/xen-legacy-backend.c (it uses qdev_set_id() and in this case,
> not for a sysbus device, so it's ok).
>
> Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>

Acked-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  include/hw/boards.h |  1 -
>  hw/core/machine.c   | 27 ---------------------------
>  2 files changed, 28 deletions(-)
>
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 934443c1cd..ccbc40355a 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -311,7 +311,6 @@ typedef struct CpuTopology {
>  struct MachineState {
>      /*< private >*/
>      Object parent_obj;
> -    Notifier sysbus_notifier;
>
>      /*< public >*/
>
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index 1a18912dc8..521438e90a 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -571,18 +571,6 @@ bool machine_class_is_dynamic_sysbus_dev_allowed(MachineClass *mc,
>      return allowed;
>  }
>
> -static void validate_sysbus_device(SysBusDevice *sbdev, void *opaque)
> -{
> -    MachineState *machine = opaque;
> -    MachineClass *mc = MACHINE_GET_CLASS(machine);
> -
> -    if (!device_is_dynamic_sysbus(mc, DEVICE(sbdev))) {
> -        error_report("Option '-device %s' cannot be handled by this machine",
> -                     object_class_get_name(object_get_class(OBJECT(sbdev))));
> -        exit(1);
> -    }
> -}
> -
>  static char *machine_get_memdev(Object *obj, Error **errp)
>  {
>      MachineState *ms = MACHINE(obj);
> @@ -598,17 +586,6 @@ static void machine_set_memdev(Object *obj, const char *value, Error **errp)
>      ms->ram_memdev_id = g_strdup(value);
>  }
>
> -static void machine_init_notify(Notifier *notifier, void *data)
> -{
> -    MachineState *machine = MACHINE(qdev_get_machine());
> -
> -    /*
> -     * Loop through all dynamically created sysbus devices and check if they are
> -     * all allowed.  If a device is not allowed, error out.
> -     */
> -    foreach_dynamic_sysbus_device(validate_sysbus_device, machine);
> -}
> -
>  HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
>  {
>      int i;
> @@ -1030,10 +1007,6 @@ static void machine_initfn(Object *obj)
>                                          "Table (HMAT)");
>      }
>
> -    /* Register notifier when init is done for sysbus sanity checks */
> -    ms->sysbus_notifier.notify = machine_init_notify;
> -    qemu_add_machine_init_done_notifier(&ms->sysbus_notifier);
> -
>      /* default to mc->default_cpus */
>      ms->smp.cpus = mc->default_cpus;
>      ms->smp.max_cpus = mc->default_cpus;
> --
> 2.33.0
>
>