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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <tip-cc5d167b58af1d858aa5a2ade158acb94af4df70@git.kernel.org>
Date:	Wed, 14 Nov 2012 13:34:16 -0800
From:	tip-bot for Fenghua Yu <fenghua.yu@...el.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...nel.org,
	fenghua.yu@...el.com, tglx@...utronix.de, hpa@...ux.intel.com
Subject: [tip:x86/bsp-hotplug] x86/i387.c:
  Initialize thread xstate only on CPU0 only once

Commit-ID:  cc5d167b58af1d858aa5a2ade158acb94af4df70
Gitweb:     http://git.kernel.org/tip/cc5d167b58af1d858aa5a2ade158acb94af4df70
Author:     Fenghua Yu <fenghua.yu@...el.com>
AuthorDate: Tue, 13 Nov 2012 11:32:50 -0800
Committer:  H. Peter Anvin <hpa@...ux.intel.com>
CommitDate: Wed, 14 Nov 2012 09:39:56 -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@...el.com>
Link: http://lkml.kernel.org/r/1352835171-3958-14-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@...ux.intel.com>
---
 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@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/