qemu/hw/arm/digic.c
Markus Armbruster 4c315c2766 qdev: Protect device-list-properties against broken devices
Several devices don't survive object_unref(object_new(T)): they crash
or hang during cleanup, or they leave dangling pointers behind.

This breaks at least device-list-properties, because
qmp_device_list_properties() needs to create a device to find its
properties.  Broken in commit f4eb32b "qmp: show QOM properties in
device-list-properties", v2.1.  Example reproducer:

    $ qemu-system-aarch64 -nodefaults -display none -machine none -S -qmp stdio
    {"QMP": {"version": {"qemu": {"micro": 50, "minor": 4, "major": 2}, "package": ""}, "capabilities": []}}
    { "execute": "qmp_capabilities" }
    {"return": {}}
    { "execute": "device-list-properties", "arguments": { "typename": "pxa2xx-pcmcia" } }
    qemu-system-aarch64: /home/armbru/work/qemu/memory.c:1307: memory_region_finalize: Assertion `((&mr->subregions)->tqh_first == ((void *)0))' failed.
    Aborted (core dumped)
    [Exit 134 (SIGABRT)]

Unfortunately, I can't fix the problems in these devices right now.
Instead, add DeviceClass member cannot_destroy_with_object_finalize_yet
to mark them:

* Hang during cleanup (didn't debug, so I can't say why):
  "realview_pci", "versatile_pci".

* Dangling pointer in cpus: most CPUs, plus "allwinner-a10", "digic",
  "fsl,imx25", "fsl,imx31", "xlnx,zynqmp", because they create such
  CPUs

* Assert kvm_enabled(): "host-x86_64-cpu", host-i386-cpu",
  "host-powerpc64-cpu", "host-embedded-powerpc-cpu",
  "host-powerpc-cpu" (the powerpc ones can't currently reach the
  assertion, because the CPUs are only registered when KVM is enabled,
  but the assertion is arguably in the wrong place all the same)

Make qmp_device_list_properties() fail cleanly when the device is so
marked.  This improves device-list-properties from "crashes, hangs or
leaves dangling pointers behind" to "fails".  Not a complete fix, just
a better-than-nothing work-around.  In the above reproducer,
device-list-properties now fails with "Can't list properties of device
'pxa2xx-pcmcia'".

This also protects -device FOO,help, which uses the same machinery
since commit ef52358 "qdev-monitor: include QOM properties in -device
FOO, help output", v2.2.  Example reproducer:

    $ qemu-system-aarch64 -machine none -device pxa2xx-pcmcia,help

Before:

    qemu-system-aarch64: .../memory.c:1307: memory_region_finalize: Assertion `((&mr->subregions)->tqh_first == ((void *)0))' failed.

After:

    Can't list properties of device 'pxa2xx-pcmcia'

Cc: "Andreas Färber" <afaerber@suse.de>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Anthony Green <green@moxielogic.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Jia Liu <proljc@gmail.com>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: qemu-ppc@nongnu.org
Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1443689999-12182-10-git-send-email-armbru@redhat.com>
2015-10-09 15:25:57 +02:00

122 lines
3.4 KiB
C

/*
* QEMU model of the Canon DIGIC SoC.
*
* Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com>
*
* This model is based on reverse engineering efforts
* made by CHDK (http://chdk.wikia.com) and
* Magic Lantern (http://www.magiclantern.fm) projects
* contributors.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include "hw/arm/digic.h"
#define DIGIC4_TIMER_BASE(n) (0xc0210000 + (n) * 0x100)
#define DIGIC_UART_BASE 0xc0800000
static void digic_init(Object *obj)
{
DigicState *s = DIGIC(obj);
DeviceState *dev;
int i;
object_initialize(&s->cpu, sizeof(s->cpu), "arm946-" TYPE_ARM_CPU);
object_property_add_child(obj, "cpu", OBJECT(&s->cpu), NULL);
for (i = 0; i < DIGIC4_NB_TIMERS; i++) {
#define DIGIC_TIMER_NAME_MLEN 11
char name[DIGIC_TIMER_NAME_MLEN];
object_initialize(&s->timer[i], sizeof(s->timer[i]), TYPE_DIGIC_TIMER);
dev = DEVICE(&s->timer[i]);
qdev_set_parent_bus(dev, sysbus_get_default());
snprintf(name, DIGIC_TIMER_NAME_MLEN, "timer[%d]", i);
object_property_add_child(obj, name, OBJECT(&s->timer[i]), NULL);
}
object_initialize(&s->uart, sizeof(s->uart), TYPE_DIGIC_UART);
dev = DEVICE(&s->uart);
qdev_set_parent_bus(dev, sysbus_get_default());
object_property_add_child(obj, "uart", OBJECT(&s->uart), NULL);
}
static void digic_realize(DeviceState *dev, Error **errp)
{
DigicState *s = DIGIC(dev);
Error *err = NULL;
SysBusDevice *sbd;
int i;
object_property_set_bool(OBJECT(&s->cpu), true, "reset-hivecs", &err);
if (err != NULL) {
error_propagate(errp, err);
return;
}
object_property_set_bool(OBJECT(&s->cpu), true, "realized", &err);
if (err != NULL) {
error_propagate(errp, err);
return;
}
for (i = 0; i < DIGIC4_NB_TIMERS; i++) {
object_property_set_bool(OBJECT(&s->timer[i]), true, "realized", &err);
if (err != NULL) {
error_propagate(errp, err);
return;
}
sbd = SYS_BUS_DEVICE(&s->timer[i]);
sysbus_mmio_map(sbd, 0, DIGIC4_TIMER_BASE(i));
}
object_property_set_bool(OBJECT(&s->uart), true, "realized", &err);
if (err != NULL) {
error_propagate(errp, err);
return;
}
sbd = SYS_BUS_DEVICE(&s->uart);
sysbus_mmio_map(sbd, 0, DIGIC_UART_BASE);
}
static void digic_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
dc->realize = digic_realize;
/*
* Reason: creates an ARM CPU, thus use after free(), see
* arm_cpu_class_init()
*/
dc->cannot_destroy_with_object_finalize_yet = true;
}
static const TypeInfo digic_type_info = {
.name = TYPE_DIGIC,
.parent = TYPE_DEVICE,
.instance_size = sizeof(DigicState),
.instance_init = digic_init,
.class_init = digic_class_init,
};
static void digic_register_types(void)
{
type_register_static(&digic_type_info);
}
type_init(digic_register_types)