mirror of https://gitee.com/openkylin/linux.git
99 lines
3.0 KiB
ReStructuredText
99 lines
3.0 KiB
ReStructuredText
Notifier error injection
|
|
========================
|
|
|
|
Notifier error injection provides the ability to inject artificial errors to
|
|
specified notifier chain callbacks. It is useful to test the error handling of
|
|
notifier call chain failures which is rarely executed. There are kernel
|
|
modules that can be used to test the following notifiers.
|
|
|
|
* PM notifier
|
|
* Memory hotplug notifier
|
|
* powerpc pSeries reconfig notifier
|
|
* Netdevice notifier
|
|
|
|
PM notifier error injection module
|
|
----------------------------------
|
|
This feature is controlled through debugfs interface
|
|
|
|
/sys/kernel/debug/notifier-error-inject/pm/actions/<notifier event>/error
|
|
|
|
Possible PM notifier events to be failed are:
|
|
|
|
* PM_HIBERNATION_PREPARE
|
|
* PM_SUSPEND_PREPARE
|
|
* PM_RESTORE_PREPARE
|
|
|
|
Example: Inject PM suspend error (-12 = -ENOMEM)::
|
|
|
|
# cd /sys/kernel/debug/notifier-error-inject/pm/
|
|
# echo -12 > actions/PM_SUSPEND_PREPARE/error
|
|
# echo mem > /sys/power/state
|
|
bash: echo: write error: Cannot allocate memory
|
|
|
|
Memory hotplug notifier error injection module
|
|
----------------------------------------------
|
|
This feature is controlled through debugfs interface
|
|
|
|
/sys/kernel/debug/notifier-error-inject/memory/actions/<notifier event>/error
|
|
|
|
Possible memory notifier events to be failed are:
|
|
|
|
* MEM_GOING_ONLINE
|
|
* MEM_GOING_OFFLINE
|
|
|
|
Example: Inject memory hotplug offline error (-12 == -ENOMEM)::
|
|
|
|
# cd /sys/kernel/debug/notifier-error-inject/memory
|
|
# echo -12 > actions/MEM_GOING_OFFLINE/error
|
|
# echo offline > /sys/devices/system/memory/memoryXXX/state
|
|
bash: echo: write error: Cannot allocate memory
|
|
|
|
powerpc pSeries reconfig notifier error injection module
|
|
--------------------------------------------------------
|
|
This feature is controlled through debugfs interface
|
|
|
|
/sys/kernel/debug/notifier-error-inject/pSeries-reconfig/actions/<notifier event>/error
|
|
|
|
Possible pSeries reconfig notifier events to be failed are:
|
|
|
|
* PSERIES_RECONFIG_ADD
|
|
* PSERIES_RECONFIG_REMOVE
|
|
* PSERIES_DRCONF_MEM_ADD
|
|
* PSERIES_DRCONF_MEM_REMOVE
|
|
|
|
Netdevice notifier error injection module
|
|
----------------------------------------------
|
|
This feature is controlled through debugfs interface
|
|
|
|
/sys/kernel/debug/notifier-error-inject/netdev/actions/<notifier event>/error
|
|
|
|
Netdevice notifier events which can be failed are:
|
|
|
|
* NETDEV_REGISTER
|
|
* NETDEV_CHANGEMTU
|
|
* NETDEV_CHANGENAME
|
|
* NETDEV_PRE_UP
|
|
* NETDEV_PRE_TYPE_CHANGE
|
|
* NETDEV_POST_INIT
|
|
* NETDEV_PRECHANGEMTU
|
|
* NETDEV_PRECHANGEUPPER
|
|
* NETDEV_CHANGEUPPER
|
|
|
|
Example: Inject netdevice mtu change error (-22 == -EINVAL)::
|
|
|
|
# cd /sys/kernel/debug/notifier-error-inject/netdev
|
|
# echo -22 > actions/NETDEV_CHANGEMTU/error
|
|
# ip link set eth0 mtu 1024
|
|
RTNETLINK answers: Invalid argument
|
|
|
|
For more usage examples
|
|
-----------------------
|
|
There are tools/testing/selftests using the notifier error injection features
|
|
for CPU and memory notifiers.
|
|
|
|
* tools/testing/selftests/cpu-hotplug/on-off-test.sh
|
|
* tools/testing/selftests/memory-hotplug/on-off-test.sh
|
|
|
|
These scripts first do simple online and offline tests and then do fault
|
|
injection tests if notifier error injection module is available.
|