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    Subject[038/145] sparc64: Fix sun4u execute bit check in TSB I-TLB load.
    2.6.32-stable review patch.  If anyone has any objections, please let me know.

    ----------------
    From: David S. Miller <davem@davemloft.net>

    [ Upstream commit 1f474646fdc36b457606bbcd6a3592e6cbd31ac4 ]

    Thanks to testcase and report from Brad Spengler:

    --------------------
    #include <stdio.h>

    typedef int (* _wee)(void);

    int main(void)
    {
    char buf[8] = { '\x81', '\xc7', '\xe0', '\x08', '\x81', '\xe8',
    '\x00', '\x00' };
    _wee wee;
    printf("%p\n", &buf);
    wee = (_wee)&buf;
    wee();

    return 0;
    }
    --------------------

    TSB I-tlb load code tries to use andcc to check the _PAGE_EXEC_4U bit,
    but that's bit 12 so it gets sign extended all the way up to bit 63
    and the test nearly always passes as a result.

    Use sethi to fix the bug.

    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    arch/sparc/kernel/tsb.S | 6 ++++--
    1 file changed, 4 insertions(+), 2 deletions(-)

    --- a/arch/sparc/kernel/tsb.S
    +++ b/arch/sparc/kernel/tsb.S
    @@ -191,10 +191,12 @@ tsb_dtlb_load:

    tsb_itlb_load:
    /* Executable bit must be set. */
    -661: andcc %g5, _PAGE_EXEC_4U, %g0
    - .section .sun4v_1insn_patch, "ax"
    +661: sethi %hi(_PAGE_EXEC_4U), %g4
    + andcc %g5, %g4, %g0
    + .section .sun4v_2insn_patch, "ax"
    .word 661b
    andcc %g5, _PAGE_EXEC_4V, %g0
    + nop
    .previous

    be,pn %xcc, tsb_do_fault



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