[v10,13/14] x86/i387.c: Initialize thread xstate only on CPU0 only once

Commit Message

Fenghua Yu Nov. 13, 2012, 7:32 p.m. UTC

From: Fenghua Yu <[e-mail]>

init_thread_xstate() is only called once to avoid overriding xstate_size during
boot time or during CPU hotplug.

Signed-off-by: Fenghua Yu <[e-mail]>
---
 arch/x86/kernel/i387.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

Patch

diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 675a050..245a71d 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -175,7 +175,11 @@  void __cpuinit fpu_init(void)
 		cr0 |= X86_CR0_EM;
 	write_cr0(cr0);
 
-	if (!smp_processor_id())
+	/*
+	 * init_thread_xstate is only called once to avoid overriding
+	 * xstate_size during boot time or during CPU hotplug.
+	 */
+	if (xstate_size == 0)
 		init_thread_xstate();
 
 	mxcsr_feature_mask_init();