diff options
| author | Richard W.M. Jones <rjones@redhat.com> | 2010-09-24 16:08:06 +0100 |
|---|---|---|
| committer | Blue Swirl <blauwirbel@gmail.com> | 2010-12-12 13:10:55 +0000 |
| commit | 36888c6335422f07bbc50bf3443a39f24b90c7c6 (patch) | |
| tree | dc83339d92d931d8e3e96c82052e507975d40ac6 /hw/wdt_ib700.c | |
| parent | 962630f207a33b7de4316022884b5241e05491cd (diff) | |
Watchdog: disable watchdog timer when hard-rebooting a guest.
This commit causes the watchdog timer to be reset when a guest is
hard-rebooted.
The failure case previously was as follows:
(a) guest boots, watchdog is enabled
(b) guest does a reset eg:
echo 'b' > /proc/sysrq-trigger
(note that an ordinary /sbin/reboot wouldn't hit this case
since as the watchdog daemon is shut down, the daemon would
properly disable the watchdog device)
(c) the reboot takes longer than the remaining time on the
watchdog
(d) the watchdog therefore fires during the reboot
(e) probably the VM would just reboot again at this point which
is pretty benign, but it could depend on the action that the
user had selected for the watchdog
Now we use the qdev reset function to register a reset handler
which disables the timer. Note the handler is called _either_
just after init _or_ when the guest reboots.
In the i6300esb case there is a small refactoring of the code so
that the device's internal state is now fully restored to defaults
on a reboot.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Diffstat (limited to 'hw/wdt_ib700.c')
| -rw-r--r-- | hw/wdt_ib700.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/hw/wdt_ib700.c b/hw/wdt_ib700.c index c34687bcac..b6235ebe52 100644 --- a/hw/wdt_ib700.c +++ b/hw/wdt_ib700.c @@ -97,6 +97,8 @@ static int wdt_ib700_init(ISADevice *dev) { IB700State *s = DO_UPCAST(IB700State, dev, dev); + ib700_debug("watchdog init\n"); + s->timer = qemu_new_timer(vm_clock, ib700_timer_expired, s); register_ioport_write(0x441, 2, 1, ib700_write_disable_reg, s); register_ioport_write(0x443, 2, 1, ib700_write_enable_reg, s); @@ -104,16 +106,26 @@ static int wdt_ib700_init(ISADevice *dev) return 0; } +static void wdt_ib700_reset(DeviceState *dev) +{ + IB700State *s = DO_UPCAST(IB700State, dev.qdev, dev); + + ib700_debug("watchdog reset\n"); + + qemu_del_timer(s->timer); +} + static WatchdogTimerModel model = { .wdt_name = "ib700", .wdt_description = "iBASE 700", }; static ISADeviceInfo wdt_ib700_info = { - .qdev.name = "ib700", - .qdev.size = sizeof(IB700State), - .qdev.vmsd = &vmstate_ib700, - .init = wdt_ib700_init, + .qdev.name = "ib700", + .qdev.size = sizeof(IB700State), + .qdev.vmsd = &vmstate_ib700, + .qdev.reset = wdt_ib700_reset, + .init = wdt_ib700_init, }; static void wdt_ib700_register_devices(void) |