So to be specific on the whole accessed/dirty bit topic.

My first intention was to ask how to do it presently, if possible.

When I found out it wasn't...I'd like to make it a suggestion for a future
version.

I'm brand new to this list, so is this the proper way to make suggetions?

On Thu, Aug 13, 2015 at 1:47 PM, Raymond Jennings <[email protected]>
wrote:

> On Thu, Aug 13, 2015 at 5:48 AM, Adrian Danis <[email protected]>
> wrote:
>
>> Currently there is no support in seL4 for taking advantage of hardware
>> support for detecting dirty/accessed pages. If you want this then you must
>> emulate this in software by changing the access writes on pages and
>> handling the resulting page faults.
>>
>> The reason for not supporting any underlying hardware features for this
>> is the original, and verified, platform that seL4 was written, an armv6,
>> did not have hardware support for tracking this.
>>
>> Since porting seL4 to x86 and newer ARM architectures that have support
>> for this there has not been any perceived need for this, so it has not been
>> done. There is certainly no reason requesting such information could not be
>> done within the capability model.
>>
>
> This is why I was asking if having mapping rights on the page
> descriptor/page table would be sufficient.  If you can change which
> physical page a virtual address refers to, you could probably also have
> enough privilege to be trusted with dirty/accessed bit.
>
> Is this the sort of "within the capability model" you are referring to?
>
>
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