• Jeremy Fitzhardinge's avatar
    x86: define PTE_MASK in a universally useful way · 2bd3a99c
    Jeremy Fitzhardinge authored
    Define PTE_MASK so that it contains a meaningful value for all x86
    pagetable configurations.  Previously it was defined as a "long" which
    means that it was too short to cover a 32-bit PAE pte entry.
    
    It is now defined as a pteval_t, which is an integer type long enough
    to contain a full pte (or pmd, pud, pgd).
    
    This fixes an Xorg crash on 32-bit x86 with PAE due to corruption of the
    NX bit in mprotect due to the incorrect type/value of PTE_MASK reported
    by Hugh Dickins:
    
      "Yes, thanks Jeremy: I've checked that each stage builds and runs X on
       my boxes here, x86_32 and x86_32+PAE and x86_64.  (So even 1/8 is
       enough to fix the PAT pte_modify issue, though 2/8 then fixes
       compiler warnings.)"
    Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
    Tested-by: default avatarHugh Dickins <hugh@veritas.com>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    2bd3a99c
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