From f1293c68aff98cd913a59b151aac938ec4ce4857 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Tue, 24 Jun 2014 08:43:34 -0400 Subject: [PATCH] watchdog: Disable watchdog on virtual machines. For various reasons, VMs seem to trigger the soft lockup detector a lot, in cases where it's just not possible for a lockup to occur. (Example: https://bugzilla.redhat.com/show_bug.cgi?id=971139) In some cases it seems that the host just never scheduled the app running the VM for a very long time (Could be the host was under heavy load). Just disable the detector on VMs. Bugzilla: 971139 Upstream-status: Fedora mustard for now Signed-off-by: Dave Jones --- kernel/watchdog.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 18f34cf..6aadffe 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -185,6 +186,32 @@ static int __init hardlockup_all_cpu_backtrace_setup(char *str) __setup("hardlockup_all_cpu_backtrace=", hardlockup_all_cpu_backtrace_setup); #endif +static int disable_watchdog(const struct dmi_system_id *d) +{ + printk(KERN_INFO "watchdog: disabled (inside virtual machine)\n"); + watchdog_user_enabled = 0; + return 0; +} + +static const struct dmi_system_id watchdog_virt_dmi_table[] = { + { + .callback = disable_watchdog, + .ident = "VMware", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "VMware, Inc."), + }, + }, + { + .callback = disable_watchdog, + .ident = "Bochs", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Bochs"), + }, + }, + {} +}; + + /* * Hard-lockup warnings should be triggered after just a few seconds. Soft- * lockups can have false positives under extreme conditions. So we generally @@ -1030,6 +1057,8 @@ out: void __init lockup_detector_init(void) { + dmi_check_system(watchdog_virt_dmi_table); + set_sample_period(); #ifdef CONFIG_NO_HZ_FULL -- 2.5.0