From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Limpach <chris@pin.lu>
Subject: pagetable pinning question
Date: Tue, 3 Feb 2004 20:21:22 +0100
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Hi!

I want to use pinning for the L1/L2 pagetables.  The currently activated
pagetable maps itself and that works great.  But I (or rather whoever wrote
the pagetable code) also wants to map inactive pagetables and this doesn't
work because of the following check in get_twisted_l2_table:
    if ( (l2v >> PAGE_SHIFT) != entry_pfn )
    {
        MEM_LOG("L2 tables may not map _other_ L2 tables!\n");

Are there counting or protection issues why this is disallowed or was it
just not needed for Linux/Windows?

I guess a work around would be to switch to the inactive pagetable and
switch back when the mapping is no longer needed...

    christian



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