Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.git

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
index 08c8a5eb25ab..575a8f657b31 100644
--- a/arch/ia64/kernel/ptrace.c
+++ b/arch/ia64/kernel/ptrace.c
@@ -635,11 +635,17 @@ ia64_flush_fph (struct task_struct *task)
 {
         struct ia64_psr *psr = ia64_psr(ia64_task_regs(task));
 
+        /*
+         * Prevent migrating this task while
+         * we're fiddling with the FPU state
+         */
+        preempt_disable();
         if (ia64_is_local_fpu_owner(task) && psr->mfh) {
                 psr->mfh = 0;
                 task->thread.flags |= IA64_THREAD_FPH_VALID;
                 ia64_save_fpu(&task->thread.fph[0]);
         }
+        preempt_enable();
 }
 
 /*