m68k: Fix assembler constraint to prevent overeager gcc optimisation

Passing the address of a variable as an operand to an asm statement
doesn't mark the value of this variable as used, so gcc may optimize its
initialisation away.  Fix this by using the "m" constraint instead.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
diff --git a/arch/m68k/atari/config.c b/arch/m68k/atari/config.c
index 273c7e8..af78731 100644
--- a/arch/m68k/atari/config.c
+++ b/arch/m68k/atari/config.c
@@ -415,9 +415,9 @@
 					 * FDC val = 4 -> Supervisor only */
 		asm volatile ("\n"
 			"	.chip	68030\n"
-			"	pmove	%0@,%/tt1\n"
+			"	pmove	%0,%/tt1\n"
 			"	.chip	68k"
-			: : "a" (&tt1_val));
+			: : "m" (tt1_val));
 	} else {
 	        asm volatile ("\n"
 			"	.chip	68040\n"
@@ -570,10 +570,10 @@
 			: "d0");
 	} else
 		asm volatile ("\n"
-			"	pmove	%0@,%%tc\n"
+			"	pmove	%0,%%tc\n"
 			"	jmp	%1@"
 			: /* no outputs */
-			: "a" (&tc_val), "a" (reset_addr));
+			: "m" (tc_val), "a" (reset_addr));
 }
 
 
diff --git a/arch/m68k/kernel/process_mm.c b/arch/m68k/kernel/process_mm.c
index 1bc223a..aa4ffb8 100644
--- a/arch/m68k/kernel/process_mm.c
+++ b/arch/m68k/kernel/process_mm.c
@@ -189,8 +189,8 @@
 	current->thread.fs = __USER_DS;
 	if (!FPU_IS_EMU)
 		asm volatile (".chip 68k/68881\n\t"
-			      "frestore %0@\n\t"
-			      ".chip 68k" : : "a" (&zero));
+			      "frestore %0\n\t"
+			      ".chip 68k" : : "m" (zero));
 }
 
 /*
diff --git a/arch/m68k/kernel/process_no.c b/arch/m68k/kernel/process_no.c
index 69c1803..5e1078c 100644
--- a/arch/m68k/kernel/process_no.c
+++ b/arch/m68k/kernel/process_no.c
@@ -163,8 +163,8 @@
 #ifdef CONFIG_FPU
 	if (!FPU_IS_EMU)
 		asm volatile (".chip 68k/68881\n\t"
-			      "frestore %0@\n\t"
-			      ".chip 68k" : : "a" (&zero));
+			      "frestore %0\n\t"
+			      ".chip 68k" : : "m" (zero));
 #endif
 }
 
diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index 89362f2..eb67469 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -552,13 +552,13 @@
 
 #ifdef DEBUG
 		asm volatile ("ptestr %3,%2@,#7,%0\n\t"
-			      "pmove %%psr,%1@"
-			      : "=a&" (desc)
-			      : "a" (&temp), "a" (addr), "d" (ssw));
+			      "pmove %%psr,%1"
+			      : "=a&" (desc), "=m" (temp)
+			      : "a" (addr), "d" (ssw));
 #else
 		asm volatile ("ptestr %2,%1@,#7\n\t"
-			      "pmove %%psr,%0@"
-			      : : "a" (&temp), "a" (addr), "d" (ssw));
+			      "pmove %%psr,%0"
+			      : "=m" (temp) : "a" (addr), "d" (ssw));
 #endif
 		mmusr = temp;
 
@@ -605,20 +605,18 @@
 			       !(ssw & RW) ? "write" : "read", addr,
 			       fp->ptregs.pc, ssw);
 			asm volatile ("ptestr #1,%1@,#0\n\t"
-				      "pmove %%psr,%0@"
-				      : /* no outputs */
-				      : "a" (&temp), "a" (addr));
+				      "pmove %%psr,%0"
+				      : "=m" (temp)
+				      : "a" (addr));
 			mmusr = temp;
 
 			printk ("level 0 mmusr is %#x\n", mmusr);
 #if 0
-			asm volatile ("pmove %%tt0,%0@"
-				      : /* no outputs */
-				      : "a" (&tlong));
+			asm volatile ("pmove %%tt0,%0"
+				      : "=m" (tlong));
 			printk("tt0 is %#lx, ", tlong);
-			asm volatile ("pmove %%tt1,%0@"
-				      : /* no outputs */
-				      : "a" (&tlong));
+			asm volatile ("pmove %%tt1,%0"
+				      : "=m" (tlong));
 			printk("tt1 is %#lx\n", tlong);
 #endif
 #ifdef DEBUG
@@ -668,13 +666,13 @@
 
 #ifdef DEBUG
 	asm volatile ("ptestr #1,%2@,#7,%0\n\t"
-		      "pmove %%psr,%1@"
-		      : "=a&" (desc)
-		      : "a" (&temp), "a" (addr));
+		      "pmove %%psr,%1"
+		      : "=a&" (desc), "=m" (temp)
+		      : "a" (addr));
 #else
 	asm volatile ("ptestr #1,%1@,#7\n\t"
-		      "pmove %%psr,%0@"
-		      : : "a" (&temp), "a" (addr));
+		      "pmove %%psr,%0"
+		      : "=m" (temp) : "a" (addr));
 #endif
 	mmusr = temp;
 
diff --git a/arch/m68k/mm/cache.c b/arch/m68k/mm/cache.c
index 5437fff..5550aa4f 100644
--- a/arch/m68k/mm/cache.c
+++ b/arch/m68k/mm/cache.c
@@ -52,9 +52,9 @@
 		unsigned long *descaddr;
 
 		asm volatile ("ptestr %3,%2@,#7,%0\n\t"
-			      "pmove %%psr,%1@"
-			      : "=a&" (descaddr)
-			      : "a" (&mmusr), "a" (vaddr), "d" (get_fs().seg));
+			      "pmove %%psr,%1"
+			      : "=a&" (descaddr), "=m" (mmusr)
+			      : "a" (vaddr), "d" (get_fs().seg));
 		if (mmusr & (MMU_I|MMU_B|MMU_L))
 			return 0;
 		descaddr = phys_to_virt((unsigned long)descaddr);