2.6.24-stable review patch.  If anyone has any objections, please let us know.

------------------
From: Thomas Gleixner <[EMAIL PROTECTED]>

The exception fixup for the futex macros __futex_atomic_op1/2 and
futex_atomic_cmpxchg_inatomic() is missing an entry when the lock
prefix is replaced by a NOP via SMP alternatives.

Chuck Ebert tracked this down from the information provided in:
https://bugzilla.redhat.com/show_bug.cgi?id=429412

A possible solution would be to add another fixup after the
LOCK_PREFIX, so both the LOCK and NOP case have their own entry in the
exception table, but it's not really worth the trouble.

Simply replace LOCK_PREFIX with lock and keep those untouched by SMP
alternatives.

Signed-off-by: Thomas Gleixner <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>

---
 include/asm-x86/futex_32.h |    6 +++---
 include/asm-x86/futex_64.h |    6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

--- a/include/asm-x86/futex_32.h
+++ b/include/asm-x86/futex_32.h
@@ -28,7 +28,7 @@
 "1:    movl    %2, %0\n\
        movl    %0, %3\n"                                       \
        insn "\n"                                               \
-"2:    " LOCK_PREFIX "cmpxchgl %3, %2\n\
+"2:    lock cmpxchgl %3, %2\n\
        jnz     1b\n\
 3:     .section .fixup,\"ax\"\n\
 4:     mov     %5, %1\n\
@@ -68,7 +68,7 @@ futex_atomic_op_inuser (int encoded_op, 
 #endif
                switch (op) {
                case FUTEX_OP_ADD:
-                       __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret,
+                       __futex_atomic_op1("lock xaddl %0, %2", ret,
                                           oldval, uaddr, oparg);
                        break;
                case FUTEX_OP_OR:
@@ -111,7 +111,7 @@ futex_atomic_cmpxchg_inatomic(int __user
                return -EFAULT;
 
        __asm__ __volatile__(
-               "1:     " LOCK_PREFIX "cmpxchgl %3, %1          \n"
+               "1:     lock cmpxchgl %3, %1                    \n"
 
                "2:     .section .fixup, \"ax\"                 \n"
                "3:     mov     %2, %0                          \n"
--- a/include/asm-x86/futex_64.h
+++ b/include/asm-x86/futex_64.h
@@ -27,7 +27,7 @@
 "1:    movl    %2, %0\n\
        movl    %0, %3\n"                                       \
        insn "\n"                                               \
-"2:    " LOCK_PREFIX "cmpxchgl %3, %2\n\
+"2:    "lock cmpxchgl %3, %2\n\
        jnz     1b\n\
 3:     .section .fixup,\"ax\"\n\
 4:     mov     %5, %1\n\
@@ -62,7 +62,7 @@ futex_atomic_op_inuser (int encoded_op, 
                __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
                break;
        case FUTEX_OP_ADD:
-               __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval,
+               __futex_atomic_op1("lock xaddl %0, %2", ret, oldval,
                                   uaddr, oparg);
                break;
        case FUTEX_OP_OR:
@@ -101,7 +101,7 @@ futex_atomic_cmpxchg_inatomic(int __user
                return -EFAULT;
 
        __asm__ __volatile__(
-               "1:     " LOCK_PREFIX "cmpxchgl %3, %1          \n"
+               "1:     lock cmpxchgl %3, %1                    \n"
 
                "2:     .section .fixup, \"ax\"                 \n"
                "3:     mov     %2, %0                          \n"

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