[Qemu-devel] [PATCH v4] bugfix: vm halt when in reset looping

[Qemu-devel] [PATCH v4] bugfix: vm halt when in reset looping

[hangaohuai]

reset mc146818rtc device when RESET event happens.

Fix the problem:
  1. Guest boot the second cpu, set CMOS_RESET_CODE 0x0a to protect selfboot;
  2. VM being reset by others, hmp_system_reset;
  3. seabios resume check the CMOS_RESET_CODE, if 0x0a, jump to the BDA
     resume execution by jump via 40h:0067h;
  4. Guest halt;

Signed-off-by: hangaohuai <hangaohuai@huawei.com>
---
 hw/timer/mc146818rtc.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index da209d0..637f872 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -946,11 +946,23 @@ static Property mc146818rtc_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+static void rtc_resetdev(DeviceState *d)
+{
+    RTCState *s = MC146818_RTC(d);
+
+    /* Reason: VM do suspend self will set 0xfe
+     * Reset any values other than 0xfe(Guest suspend case) */
+    if (s->cmos_data[0x0f] != 0xfe) {
+        s->cmos_data[0x0f] = 0x00;
+    }
+}
+
 static void rtc_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     dc->realize = rtc_realizefn;
+    dc->reset = rtc_resetdev;
     dc->vmsd = &vmstate_rtc;
     dc->props = mc146818rtc_properties;
     /* Reason: needs to be wired up by rtc_init() */
-- 
1.8.3.1

Re: [Qemu-devel] [PATCH v4] bugfix: vm halt when in reset looping

[Gonglei (Arei)]

>
> From: Hangaohuai
> Sent: Monday, December 19, 2016 2:04 PM
> To: qemu-devel@nongnu.org
> Cc: mst@redhat.com; pbonzini@redhat.com; Gonglei (Arei); Hangaohuai
> Subject: [PATCH v4] bugfix: vm halt when in reset looping
> 
> reset mc146818rtc device when RESET event happens.
> 
> Fix the problem:
>   1. Guest boot the second cpu, set CMOS_RESET_CODE 0x0a to protect
> selfboot;
>   2. VM being reset by others, hmp_system_reset;
>   3. seabios resume check the CMOS_RESET_CODE, if 0x0a, jump to the BDA
>      resume execution by jump via 40h:0067h;
>   4. Guest halt;
> 
> Signed-off-by: hangaohuai <hangaohuai@huawei.com>
> ---
>  hw/timer/mc146818rtc.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 

Reviewed-by: Gonglei <arei.gonglei@huawei.com>

Paolo, could you pls pick up this patch?

Thanks,
-Gonglei

> diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
> index da209d0..637f872 100644
> --- a/hw/timer/mc146818rtc.c
> +++ b/hw/timer/mc146818rtc.c
> @@ -946,11 +946,23 @@ static Property mc146818rtc_properties[] = {
>      DEFINE_PROP_END_OF_LIST(),
>  };
> 
> +static void rtc_resetdev(DeviceState *d)
> +{
> +    RTCState *s = MC146818_RTC(d);
> +
> +    /* Reason: VM do suspend self will set 0xfe
> +     * Reset any values other than 0xfe(Guest suspend case) */
> +    if (s->cmos_data[0x0f] != 0xfe) {
> +        s->cmos_data[0x0f] = 0x00;
> +    }
> +}
> +
>  static void rtc_class_initfn(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> 
>      dc->realize = rtc_realizefn;
> +    dc->reset = rtc_resetdev;
>      dc->vmsd = &vmstate_rtc;
>      dc->props = mc146818rtc_properties;
>      /* Reason: needs to be wired up by rtc_init() */
> --
> 1.8.3.1
> 

Re: [Qemu-devel] [PATCH v4] bugfix: vm halt when in reset looping

[Paolo Bonzini]

On 09/01/2017 10:08, Gonglei (Arei) wrote:
>>
>> From: Hangaohuai
>> Sent: Monday, December 19, 2016 2:04 PM
>> To: qemu-devel@nongnu.org
>> Cc: mst@redhat.com; pbonzini@redhat.com; Gonglei (Arei); Hangaohuai
>> Subject: [PATCH v4] bugfix: vm halt when in reset looping
>>
>> reset mc146818rtc device when RESET event happens.
>>
>> Fix the problem:
>>   1. Guest boot the second cpu, set CMOS_RESET_CODE 0x0a to protect
>> selfboot;
>>   2. VM being reset by others, hmp_system_reset;
>>   3. seabios resume check the CMOS_RESET_CODE, if 0x0a, jump to the BDA
>>      resume execution by jump via 40h:0067h;
>>   4. Guest halt;
>>
>> Signed-off-by: hangaohuai <hangaohuai@huawei.com>
>> ---
>>  hw/timer/mc146818rtc.c | 12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
> 
> Reviewed-by: Gonglei <arei.gonglei@huawei.com>
> 
> Paolo, could you pls pick up this patch?

Yes, it's queued.  Maybe this week--sorry for the delay.

Paolo

> Thanks,
> -Gonglei
> 
>> diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
>> index da209d0..637f872 100644
>> --- a/hw/timer/mc146818rtc.c
>> +++ b/hw/timer/mc146818rtc.c
>> @@ -946,11 +946,23 @@ static Property mc146818rtc_properties[] = {
>>      DEFINE_PROP_END_OF_LIST(),
>>  };
>>
>> +static void rtc_resetdev(DeviceState *d)
>> +{
>> +    RTCState *s = MC146818_RTC(d);
>> +
>> +    /* Reason: VM do suspend self will set 0xfe
>> +     * Reset any values other than 0xfe(Guest suspend case) */
>> +    if (s->cmos_data[0x0f] != 0xfe) {
>> +        s->cmos_data[0x0f] = 0x00;
>> +    }
>> +}
>> +
>>  static void rtc_class_initfn(ObjectClass *klass, void *data)
>>  {
>>      DeviceClass *dc = DEVICE_CLASS(klass);
>>
>>      dc->realize = rtc_realizefn;
>> +    dc->reset = rtc_resetdev;
>>      dc->vmsd = &vmstate_rtc;
>>      dc->props = mc146818rtc_properties;
>>      /* Reason: needs to be wired up by rtc_init() */
>> --
>> 1.8.3.1
>>
>