1 files changed, 9 insertions, 12 deletions

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index d3f0b6d452fb..177bba78fb0b 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -497,6 +497,15 @@ static long restore_user_regs(struct pt_regs *regs,
         if (err)
                 return 1;
 
+        /*
+         * Do this before updating the thread state in
+         * current->thread.fpr/vr/evr.  That way, if we get preempted
+         * and another task grabs the FPU/Altivec/SPE, it won't be
+         * tempted to save the current CPU state into the thread_struct
+         * and corrupt what we are writing there.
+         */
+        discard_lazy_cpu_state();
+
         /* force the process to reload the FP registers from
            current->thread when it next does FP instructions */
         regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
@@ -538,18 +547,6 @@ static long restore_user_regs(struct pt_regs *regs,
                 return 1;
 #endif /* CONFIG_SPE */
 
-#ifndef CONFIG_SMP
-        preempt_disable();
-        if (last_task_used_math == current)
-                last_task_used_math = NULL;
-        if (last_task_used_altivec == current)
-                last_task_used_altivec = NULL;
-#ifdef CONFIG_SPE
-        if (last_task_used_spe == current)
-                last_task_used_spe = NULL;
-#endif
-        preempt_enable();
-#endif
         return 0;
 }