RE: Calculating kernel logical address ..

[Imran Badr]

-----Original Message-----
From: Manfred Spraul [mailto:[e-mail]]
Sent: Monday, September 09, 2002 2:02 PM
To: Imran Badr; [e-mail]
Subject: RE: Calculating kernel logical address ..

>>As long as you can be sure they won't spontaneously vanish on you.
>
>>--
>>Daniel
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>
>
> down(&current->mm->mmap_sem) would help.
>

>Wrong. Acquiring the mmap semaphore does NOT prevent the swapper from
>swapping out pages.

>Only the page_table_lock prevents the swapper from touching a task.

>--
>	Manfred

I think you missed the whole context of the discussion. The next step is to
call get_user_pages() which takes appropriate actions to prevent page swaps.

Thanks,
Imran.