Re: [Qemu-devel] [6453] x86: Issue reset on triple faults (Jan Kiszka)

[Kevin Wolf <kwolf@suse.de>]

Jan Kiszka schrieb:
> Kevin Wolf wrote:
>> Anthony Liguori schrieb:
>>> Revision: 6453
>>>           http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6453
>>> Author:   aliguori
>>> Date:     2009-01-26 19:54:36 +0000 (Mon, 26 Jan 2009)
>>>
>>> Log Message:
>>> -----------
>>> x86: Issue reset on triple faults (Jan Kiszka)
>>>
>>> As discussed a few times on this list: A triple fault causes a system
>>> reset on x86, and some guests make use of this (e.g. 386BSD). To keep
>>> the chance of tracing unexpected resets, log them if CPU_LOG_RESET is
>>> set.
>>>
>>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>>
>>> Modified Paths:
>>> --------------
>>>     trunk/target-i386/op_helper.c
>>>
>>> Modified: trunk/target-i386/op_helper.c
>>> ===================================================================
>>> --- trunk/target-i386/op_helper.c	2009-01-26 19:54:31 UTC (rev 6452)
>>> +++ trunk/target-i386/op_helper.c	2009-01-26 19:54:36 UTC (rev 6453)
>>> @@ -1251,6 +1251,9 @@
>>>      }
>>>  }
>>>  
>>> +/* This should come from sysemu.h - if we could include it here... */
>>> +void qemu_system_reset_request(void);
>>> +
>>>  /*
>>>   * Check nested exceptions and change to double or triple fault if
>>>   * needed. It should only be called, if this is not an interrupt.
>>> @@ -1267,9 +1270,19 @@
>>>      qemu_log_mask(CPU_LOG_INT, "check_exception old: 0x%x new 0x%x\n",
>>>                  env->old_exception, intno);
>>>  
>>> -    if (env->old_exception == EXCP08_DBLE)
>>> -        cpu_abort(env, "triple fault");
>>> +#if !defined(CONFIG_USER_ONLY)
>>> +    if (env->old_exception == EXCP08_DBLE) {
>>> +        if (env->hflags & HF_SVMI_MASK)
>>> +            helper_vmexit(SVM_EXIT_SHUTDOWN, 0); /* does not return */
>>>  
>>> +        if (loglevel & CPU_LOG_RESET)
>>> +            fprintf(logfile, "Triple fault\n");
>> I think this one should use the new logging macros as well.
> 
> Or in other words:
> 
> --------->
> 
> Use new logging API.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> 
> diff --git a/target-i386/op_helper.c b/target-i386/op_helper.c
> index 8cf3bb2..edf569e 100644
> --- a/target-i386/op_helper.c
> +++ b/target-i386/op_helper.c
> @@ -1275,7 +1275,7 @@ static int check_exception(int intno, int *error_code)
>          if (env->hflags & HF_SVMI_MASK)
>              helper_vmexit(SVM_EXIT_SHUTDOWN, 0); /* does not return */
>  
> -        if (loglevel & CPU_LOG_RESET)
> +        if (qemu_loglevel_mask(CPU_LOG_RESET))
>              fprintf(logfile, "Triple fault\n");
>  
>          qemu_system_reset_request();

Well, no. There's still a fprintf on logfile. ;-)

qemu_log_mask(CPU_LOG_RESET, "Triple fault\n") should do the right thing.

Kevin