[Qemu-devel] Re: [PATCH] Reboot CPU on triple fault

[Jan Kiszka]

Kevin Wolf wrote:
> Jamie Lokier schrieb:
>> Kevin Wolf wrote:
>>> And honestly, a message on stderr really shouldn't hurt those 286 folks.
>> For old MS-DOS apps / OSes, I have the impression this can happen
>> hundreds of times per second.  It's part of task context switching and
>> BIOS calls.
> 
> I have to admit that I'm all but an 286 PM expert. What exactly is a
> triple fault doing there? If it leads to a reset as implemented here, I
> can hardly imagine that it is of much use in regular context switching.

According to my current information, the triple fault will make the
processor issue a shutdown cycle on its external bus. This is obviously
detected by many PC boards, which then issue a hard reset.

Jan

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