lkml.org 
[lkml]   [2014]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5/5] kvm: ensure hard lockup detection is disabled by default
Date
From: Ulrich Obergfell <uobergfe@redhat.com>

Use watchdog_enable_hardlockup_detector() to set hard lockup detection's
default value to false. It's risky to run this detection in a guest, as
false positives are easy to trigger, especially if the host is
overcommitted.

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
---
arch/x86/kernel/kvm.c | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 3dd8e2c..95c3cb1 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -35,6 +35,7 @@
#include <linux/slab.h>
#include <linux/kprobes.h>
#include <linux/debugfs.h>
+#include <linux/nmi.h>
#include <asm/timer.h>
#include <asm/cpu.h>
#include <asm/traps.h>
@@ -499,6 +500,13 @@ void __init kvm_guest_init(void)
#else
kvm_guest_cpu_init();
#endif
+
+ /*
+ * Hard lockup detection is enabled by default. Disable it, as guests
+ * can get false positives too easily, for example if the host is
+ * overcommitted.
+ */
+ watchdog_enable_hardlockup_detector(false);
}

static noinline uint32_t __kvm_cpuid_base(void)
--
1.7.1


\
 
 \ /
  Last update: 2014-08-11 17:21    [W:0.151 / U:0.168 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site