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    Subject[patch 13/29] ARM: fix fls() for 64-bit arguments
    2.6.25-stable review patch.  If anyone has any objections, please let us 
    know.

    ------------------
    From: Andrew Morton <akpm@linux-foundation.org>

    commit 0c65f459ce6c8bd873a61b3ae1e57858ab1debf3 upstream

    arm's fls() is implemented as a macro, causing it to misbehave when passed
    64-bit arguments. Fix.

    Cc: Nickolay Vinogradov <nickolay@protei.ru>
    Tested-by: Krzysztof Halasa <khc@pm.waw.pl>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    include/asm-arm/bitops.h | 9 ++++++++-
    1 file changed, 8 insertions(+), 1 deletion(-)

    --- a/include/asm-arm/bitops.h
    +++ b/include/asm-arm/bitops.h
    @@ -277,9 +277,16 @@ static inline int constant_fls(int x)
    * the clz instruction for much better code efficiency.
    */

    -#define fls(x) \
    +#define __fls(x) \
    ( __builtin_constant_p(x) ? constant_fls(x) : \
    ({ int __r; asm("clz\t%0, %1" : "=r"(__r) : "r"(x) : "cc"); 32-__r; }) )
    +
    +/* Implement fls() in C so that 64-bit args are suitably truncated */
    +static inline int fls(int x)
    +{
    + return __fls(x);
    +}
    +
    #define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
    #define __ffs(x) (ffs(x) - 1)
    #define ffz(x) __ffs( ~(x) )
    --


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