lkml.org 
[lkml]   [2018]   [Aug]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.18 74/79] x86/speculation/l1tf: Invert all not present mappings
    Date
    4.18-stable review patch.  If anyone has any objections, please let me know.

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

    From: Andi Kleen <ak@linux.intel.com>

    For kernel mappings PAGE_PROTNONE is not necessarily set for a non present
    mapping, but the inversion logic explicitely checks for !PRESENT and
    PROT_NONE.

    Remove the PROT_NONE check and make the inversion unconditional for all not
    present mappings.

    Signed-off-by: Andi Kleen <ak@linux.intel.com>
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    arch/x86/include/asm/pgtable-invert.h | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/arch/x86/include/asm/pgtable-invert.h
    +++ b/arch/x86/include/asm/pgtable-invert.h
    @@ -6,7 +6,7 @@

    static inline bool __pte_needs_invert(u64 val)
    {
    - return (val & (_PAGE_PRESENT|_PAGE_PROTNONE)) == _PAGE_PROTNONE;
    + return !(val & _PAGE_PRESENT);
    }

    /* Get a mask to xor with the page table entry to get the correct pfn. */

    \
     
     \ /
      Last update: 2018-08-14 20:10    [W:4.050 / U:0.224 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site