[SRU][X][B][F][PATCH 0/1] Do not initiate shutdown for EPOW_SHUTDOWN_ON_UPS event (LP: 1893897)

[patricia.domingues at canonical.com]

BugLink: https://bugs.launchpad.net/bugs/1893897

SRU Justification:

[Impact]

* With commit 79872e35469b "powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown" it was introduced that all EPOW_SYSTEM_SHUTDOWN events cause immediate shutdowns.

* But on LPARs there is a user space tool (rtas_errd) that monitor for EPOW_SHUTDOWN_ON_UPS events.

* Once rtas_errd gets an event it initiates a shutdown after predefined time.

* Therefore immediate shutdowns must not be triggered if the system is running on UPS (means for EPOW_SHUTDOWN_ON_UPS events).

[Fix]

* 90a9b102eddf6a3f987d15f4454e26a2532c1c98 90a9b102eddf "powerpc/pseries: Do not initiate shutdown when system is running on UPS"

[Test Case]

* Setup a Power system on (D)LPAR and run it on UPS with Ubuntu 16.04 or higher (kernel 4.x is needed).

* Verify that the user space tool (rtas_errd) is active and running.

* Define a time for a potential shutdown in case an EPOW_SHUTDOWN_ON_UPS event occurs.

* Trigger an EPOW_SHUTDOWN_ON_UPS event.

* Verify if the system got shutdown immediately - or after the pre-defined time.

[Regression Potential]

* The regression risk is very low, because of the very limited modification in a case statement for EPOW_SHUTDOWN_ON_UPS events.

* What may happen is that the system doesn't power off anymore if running on UPS due to the EPOW_SHUTDOWN_ON_UPS case changes - especially if there is a potential problem with rtas_errd that should monitor for these events and should initiate the delayed shutdown.

* Other than that I cannot see much potential harm.

[Other]

* The patch got upstream accepted in v5.9-rc2 and already landed in groovy's kernel 'Ubuntu-5.8.0-18.19', based on the v5.8.4 upstream stable release ticket LP 1893048.


Vasant Hegde (1):
  powerpc/pseries: Do not initiate shutdown when system is running on
    UPS

 arch/powerpc/platforms/pseries/ras.c | 1 -
 1 file changed, 1 deletion(-)

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2.17.1