s390/process: fix sfpc inline assembly

commit e47994dd44bcb4a77b4152bd0eada585934703c0 upstream.

The sfpc inline assembly within execve_tail() may incorrectly set bits
28-31 of the sfpc instruction to a value which is not zero.
These bits however are currently unused and therefore should be zero
so we won't get surprised if these bits will be used in the future.

Therefore remove the second operand from the inline assembly.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 53088e208427f1b79b2471e735ec2faede2b7d94..2ba12263f8d48001d875d5f1782e2305a16f6f58 100644 (file)
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -250,7 +250,7 @@ asmlinkage void execve_tail(void)
 {
        current->thread.fp_regs.fpc = 0;
        if (MACHINE_HAS_IEEE)
-               asm volatile("sfpc %0,%0" : : "d" (0));
+               asm volatile("sfpc %0" : : "d" (0));
 }
 
 /*