[MIPS] Make sure cpu_has_fpu is used only in atomic context

Make sure cpu_has_fpu (which uses smp_processor_id()) is used only in
atomic context.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 10 insertions, 8 deletions

diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index 362d1728e531..258d74fd0b63 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -106,6 +106,7 @@ int ptrace_setregs (struct task_struct *child, __s64 __user *data)
 int ptrace_getfpregs (struct task_struct *child, __u32 __user *data)
 {
         int i;
+        unsigned int tmp;
 
         if (!access_ok(VERIFY_WRITE, data, 33 * 8))
                 return -EIO;
@@ -121,10 +122,10 @@ int ptrace_getfpregs (struct task_struct *child, __u32 __user *data)
 
         __put_user (child->thread.fpu.fcr31, data + 64);
 
+        preempt_disable();
         if (cpu_has_fpu) {
-                unsigned int flags, tmp;
+                unsigned int flags;
 
-                preempt_disable();
                 if (cpu_has_mipsmt) {
                         unsigned int vpflags = dvpe();
                         flags = read_c0_status();
@@ -138,11 +139,11 @@ int ptrace_getfpregs (struct task_struct *child, __u32 __user *data)
                         __asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));
                         write_c0_status(flags);
                 }
-                preempt_enable();
-                __put_user (tmp, data + 65);
         } else {
-                __put_user ((__u32) 0, data + 65);
+                tmp = 0;
         }
+        preempt_enable();
+        __put_user (tmp, data + 65);
 
         return 0;
 }
@@ -245,16 +246,17 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                         unsigned int mtflags;
 #endif /* CONFIG_MIPS_MT_SMTC */
 
-                        if (!cpu_has_fpu)
+                        preempt_disable();
+                        if (!cpu_has_fpu) {
+                                preempt_enable();
                                 break;
+                        }
 
 #ifdef CONFIG_MIPS_MT_SMTC
                         /* Read-modify-write of Status must be atomic */
                         local_irq_save(irqflags);
                         mtflags = dmt();
 #endif /* CONFIG_MIPS_MT_SMTC */
-
-                        preempt_disable();
                         if (cpu_has_mipsmt) {
                                 unsigned int vpflags = dvpe();
                                 flags = read_c0_status();