Gabriel Paubert wrote:
>> And shouldn't CR3 be intitialized in case anyone actually wants to
>> switch back to the kernel TSS?
>
> For now no, since the only task gate ever taken (double fault), never
> returns (you don't want to update the TSS's CR3 field on every
> switch_to() so you would have to do it in the task gate return
> path, as well as having a correct LDT field).
I want to write a TSS-based debug exception handler that just does
an iret when it gets invoked. For now it looks easier to just keep
CR3 up-to-date on every switch.
> However, returning from a task gate is so much fraught with races wrt
> segment registers that the best thing to do is to avoid it.
Even with interrupts off?
------
Chuck
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This archive was generated by hypermail 2b29 : Wed Apr 30 2003 - 22:00:33 EST