[tip:x86/bsp-hotplug] x86/i387.c: Initialize thread xstate only on CPU0 only once

From: tip-bot for Fenghua Yu
Date: Wed Nov 14 2012 - 19:28:08 EST


Commit-ID: 6f5298c2139b06925037490367906f3d73955b86
Gitweb: http://git.kernel.org/tip/6f5298c2139b06925037490367906f3d73955b86
Author: Fenghua Yu <fenghua.yu@xxxxxxxxx>
AuthorDate: Tue, 13 Nov 2012 11:32:50 -0800
Committer: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
CommitDate: Wed, 14 Nov 2012 15:28:11 -0800

x86/i387.c: Initialize thread xstate only on CPU0 only once

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

Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1352835171-3958-14-git-send-email-fenghua.yu@xxxxxxxxx
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/kernel/i387.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

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();
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/