linux-kernel - [PATCH 55/79] [PATCH] calibrate delay with irqs enabled

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]

Date:	Wed, 19 Mar 2008 14:25:50 -0300
From:	Glauber de Oliveira Costa <gcosta@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	akpm@...ux-foundation.org, tglx@...utronix.de, mingo@...e.hu,
	ak@...e.de, Glauber Costa <gcosta@...hat.com>
Subject: [PATCH 55/79] [PATCH] calibrate delay with irqs enabled

From: Glauber Costa <gcosta@...hat.com>

We do it to make it close to x86_64. The later needs it,
otherwise the nmi watchdog can get into the scene and kill us
with a hammer.

Enabling irqs here used to trigger a bug in i386. This is because
time irq handling relies upon structures that are only initialized
after smp initcalls (More precisely, it will find
per_cpu(hrtimer_bases, cpu)->cb_pending list not initialized and crash)

Signed-off-by: Glauber Costa <gcosta@...hat.com>
---
 arch/x86/kernel/smpboot_32.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/smpboot_32.c b/arch/x86/kernel/smpboot_32.c
index dbfaeb3..bd2f886 100644
--- a/arch/x86/kernel/smpboot_32.c
+++ b/arch/x86/kernel/smpboot_32.c
@@ -167,7 +167,9 @@ static void __cpuinit smp_callin(void)
 	/*
 	 * Get our bogomips.
 	 */
+	local_irq_enable();
 	calibrate_delay();
+	local_irq_disable();
 	Dprintk("Stack at about %p\n",&cpuid);
 
 	/*
-- 
1.5.0.6

--
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/