yadlapati
commented
3 months ago From Chris Cain:
The IPMI request ends up writing the power cap to the dbus. occ-control gets notified after the cap gets written, and sees that it is out of bounds so it corrects it to a legal value.
The supported power limits are on dbus:
busctl -l introspect xyz.openbmc_project.Settings /xyz/openbmc_project/control/host0/power_cap
NAME TYPE SIGNATURE RESULT/VALUE FLAGS org.freedesktop.DBus.Introspectable interface - - - .Introspect method - s - org.freedesktop.DBus.Peer interface - - - .GetMachineId method - s - .Ping method - - - org.freedesktop.DBus.Properties interface - - - .Get method ss v - .GetAll method s a{sv} - .Set method ssv - - .PropertiesChanged signal sa{sv}as - - xyz.openbmc_project.Control.Power.Cap interface - - - .CorrectionTime property t 0 emits-change writable .ExceptionAction property s "xyz.openbmc_project.Control.Power.Cap.ExceptionActions.NoAction" emits-change writable .MaxPowerCapValue property u 2777 emits-change writable .MinPowerCapValue property u 1286 emits-change writable .MinSoftPowerCapValue property u 556 emits-change writable .PowerCap property u 2777 emits-change writable
occ-control could log an error when it has to modify the cap to be within range, but the IPMI command would still be successful (user would NOT know unless they looked for PELs after the set) I would expect the ipmi command to fail if the limit was not in a valid range (between MinSoftPowerCapValue and MaxPowerCapValue).
I do see the following yaml file which should be establishing some limits for power cap: https://github.com/ibm-openbmc/openbmc/blob/1050/meta-ibm/recipes-phosphor/settings/phosphor-settings-read-settings-mrw-native/mrw-override-settings.yaml
Not sure how that settings would be enforced (obviously it is currently not enforced).
mzipse
lxwinspur
cjcain
Description
======================
Invalid power cap value is set via IPMI.
System details
=================
System : bonn008(service/0penBmc0)
BMC fw : fw1060.00-4.33-1060.2410.20240308a (NL1060_033)
Steps to re- create
======================
Step1 : Login to system
Step2: Executing the IPMI command to set the power cap value 600 and 500 , Min and Max value is 583 and 3982:
Value 600:
bash-4.2$ ipmitool -I lanplus -C 17 -N 3 -p 623 -U ipmi_admin -H bonn008.aus.stglabs.ibm.com dcmi power set_limit limit 600
Password:
Current Limit State: Power Limit Active
Exception actions: Hard Power Off & Log Event to SEL
Power Limit: 600 Watts
Correction time: 0 milliseconds
Sampling period: 0 seconds
Value 600 is set successfully
Step3:
Value 500:
bash-4.2$ ipmitool -I lanplus -C 17 -N 3 -p 623 -U ipmi_admin -H bonn008.aus.stglabs.ibm.com dcmi power set_limit limit 500
Password:
Current Limit State: Power Limit Active
Exception actions: Hard Power Off & Log Event to SEL
Power Limit: 500 Watts
Correction time: 0 milliseconds
Sampling period: 0 seconds
The Value 500 is below the minimum value ,but its taking the value has 556
Actual behaviour: Able to set a invalid value(below the minimum power cap value ) and with no error response for invalid value its able to set a random value.
Expected Behaviour: Need to get a error for setting a below minimum power cap value .