From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mukesh Rathor <mukesh.rathor@oracle.com>
Subject: HYBRID: max_mapped_pfn in ept_set_entry()
Date: Wed, 28 Mar 2012 17:08:10 -0700
Message-ID: <20120328170810.332f0b93@mantra.us.oracle.com>
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Hi guys,

I've a question. For my hybrid (PV in HVM) dom0 I do 1-1 mapping for 
mmio pages.  So, gpfn 000fbf23 maps to 000fbf23 in EPT. The
max_mapped_pfn is not adjusted in ept_set_entry() because the mfn is
not valid: 

    if ( mfn_valid(mfn_x(mfn)) &&
         (gfn + (1UL << order) - 1 > p2m->max_mapped_pfn) )
         p2m->max_mapped_pfn = gfn + (1UL << order) - 1;

As a result, clear_mmio_p2m_entry() fails because ept_get_entry() fails
because:
    if ( gfn > p2m->max_mapped_pfn )
            goto out;


I'm trying to figure the right thing to do here. Should I just change
the "gfn > p2m->max_mapped_pfn" in ept_get_entry() to check for
INVALID_MFN? I really shouldn't be adjusting max_mapped_pfn for MMIO
pages, right?

thanks,
Mukesh