[PATCH 4/4] x86/fpu: don't abuse drop_init_fpu() in flush_thread()

Oleg Nesterov
2015-03-11T17:37:24Z

drop_init_fpu() makes no sense. We need drop_fpu() and only if
!use_eager_fpu().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
arch/x86/kernel/process.c | 11 ++++-------
1 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index c396de2..2e71120 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -131,14 +131,11 @@ void flush_thread(void)
flush_ptrace_hw_breakpoint(tsk);
memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));

- drop_init_fpu(tsk);
- /*
- * Free the FPU state for non xsave platforms. They get reallocated
- * lazily at the first use.
- */
- if (!use_eager_fpu())
+ if (!use_eager_fpu()) {
+ /* FPU state will be reallocated lazily at the first use. */
+ drop_fpu(tsk);
free_thread_xstate(tsk);
- else if (!used_math()) {
+ } else if (!used_math()) {
/* kthread execs. TODO: cleanup this horror. */
if (WARN_ON(init_fpu(current)))
force_sig(SIGKILL, current);
--
1.5.5.1