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Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Sorry, meant to push out this batch earlier this weekend"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, fpu, amd: Clear exceptions in AMD FXSAVE workaround
  ftrace/x86: Load ftrace_ops in parameter not the variable holding it
Linus Torvalds 11 years ago
parent
commit
061f49ec2d
3 changed files with 10 additions and 9 deletions
  1. 7 6
      arch/x86/include/asm/fpu-internal.h
  2. 2 2
      arch/x86/kernel/entry_32.S
  3. 1 1
      arch/x86/kernel/entry_64.S

+ 7 - 6
arch/x86/include/asm/fpu-internal.h

@@ -293,12 +293,13 @@ static inline int restore_fpu_checking(struct task_struct *tsk)
 	/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
 	   is pending.  Clear the x87 state here by setting it to fixed
 	   values. "m" is a random variable that should be in L1 */
-	alternative_input(
-		ASM_NOP8 ASM_NOP2,
-		"emms\n\t"		/* clear stack tags */
-		"fildl %P[addr]",	/* set F?P to defined value */
-		X86_FEATURE_FXSAVE_LEAK,
-		[addr] "m" (tsk->thread.fpu.has_fpu));
+	if (unlikely(static_cpu_has(X86_FEATURE_FXSAVE_LEAK))) {
+		asm volatile(
+			"fnclex\n\t"
+			"emms\n\t"
+			"fildl %P[addr]"	/* set F?P to defined value */
+			: : [addr] "m" (tsk->thread.fpu.has_fpu));
+	}
 
 	return fpu_restore_checking(&tsk->thread.fpu);
 }

+ 2 - 2
arch/x86/kernel/entry_32.S

@@ -1082,7 +1082,7 @@ ENTRY(ftrace_caller)
 	pushl $0	/* Pass NULL as regs pointer */
 	movl 4*4(%esp), %eax
 	movl 0x4(%ebp), %edx
-	leal function_trace_op, %ecx
+	movl function_trace_op, %ecx
 	subl $MCOUNT_INSN_SIZE, %eax
 
 .globl ftrace_call
@@ -1140,7 +1140,7 @@ ENTRY(ftrace_regs_caller)
 	movl 12*4(%esp), %eax	/* Load ip (1st parameter) */
 	subl $MCOUNT_INSN_SIZE, %eax	/* Adjust ip */
 	movl 0x4(%ebp), %edx	/* Load parent ip (2nd parameter) */
-	leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
+	movl function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
 	pushl %esp		/* Save pt_regs as 4th parameter */
 
 GLOBAL(ftrace_regs_call)

+ 1 - 1
arch/x86/kernel/entry_64.S

@@ -88,7 +88,7 @@ END(function_hook)
 	MCOUNT_SAVE_FRAME \skip
 
 	/* Load the ftrace_ops into the 3rd parameter */
-	leaq function_trace_op, %rdx
+	movq function_trace_op(%rip), %rdx
 
 	/* Load ip into the first parameter */
 	movq RIP(%rsp), %rdi