File 65b27990-x86-p2m-pt-off-by-1-in-entry-check.patch of Package xen.32845

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File 65b27990-x86-p2m-pt-off-by-1-in-entry-check.patch of Package xen.32845

# Commit 610775d0dd61c1bd2f4720c755986098e6a5bafd
# Date 2024-01-25 16:09:04 +0100
# Author Roger Pau Monné <roger.pau@citrix.com>
# Committer Jan Beulich <jbeulich@suse.com>
x86/p2m-pt: fix off by one in entry check assert

The MMIO RO rangeset overlap check is bogus: the rangeset is inclusive so the
passed end mfn should be the last mfn to be mapped (not last + 1).

Fixes: 6fa1755644d0 ('amd/npt/shadow: replace assert that prevents creating 2M/1G MMIO entries')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@cloud.com>

--- a/xen/arch/x86/mm/p2m-pt.c
+++ b/xen/arch/x86/mm/p2m-pt.c
@@ -564,7 +564,7 @@ static void check_entry(mfn_t mfn, p2m_t
     if ( new == p2m_mmio_direct )
         ASSERT(!mfn_eq(mfn, INVALID_MFN) &&
                !rangeset_overlaps_range(mmio_ro_ranges, mfn_x(mfn),
-                                        mfn_x(mfn) + (1ul << order)));
+                                        mfn_x(mfn) + (1UL << order) - 1));
     else if ( p2m_allows_invalid_mfn(new) || new == p2m_invalid ||
               new == p2m_mmio_dm )
         ASSERT(mfn_valid(mfn) || mfn_eq(mfn, INVALID_MFN));

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File 65b27990-x86-p2m-pt-off-by-1-in-entry-check.patch of Package xen.32845

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