lkml.org 
[lkml]   [2016]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.4 001/137] x86/mm: Fix types used in pgprot cacheability flags translations
    Date
    4.4-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Jan Beulich <JBeulich@suse.com>

    commit 3625c2c234ef66acf21a72d47a5ffa94f6c5ebf2 upstream.

    For PAE kernels "unsigned long" is not suitable to hold page protection
    flags, since _PAGE_NX doesn't fit there. This is the reason for quite a
    few W+X pages getting reported as insecure during boot (observed namely
    for the entire initrd range).

    Fixes: 281d4078be ("x86: Make page cache mode a real type")
    Signed-off-by: Jan Beulich <jbeulich@suse.com>
    Reviewed-by: Juergen Gross <JGross@suse.com>
    Link: http://lkml.kernel.org/r/56A7635602000078000CAFF1@prv-mh.provo.novell.com
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    arch/x86/include/asm/pgtable_types.h | 6 ++----
    1 file changed, 2 insertions(+), 4 deletions(-)

    --- a/arch/x86/include/asm/pgtable_types.h
    +++ b/arch/x86/include/asm/pgtable_types.h
    @@ -363,20 +363,18 @@ static inline enum page_cache_mode pgpro
    }
    static inline pgprot_t pgprot_4k_2_large(pgprot_t pgprot)
    {
    + pgprotval_t val = pgprot_val(pgprot);
    pgprot_t new;
    - unsigned long val;

    - val = pgprot_val(pgprot);
    pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
    ((val & _PAGE_PAT) << (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));
    return new;
    }
    static inline pgprot_t pgprot_large_2_4k(pgprot_t pgprot)
    {
    + pgprotval_t val = pgprot_val(pgprot);
    pgprot_t new;
    - unsigned long val;

    - val = pgprot_val(pgprot);
    pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
    ((val & _PAGE_PAT_LARGE) >>
    (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));

    \
     
     \ /
      Last update: 2016-02-24 05:21    [W:4.020 / U:0.080 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site