diff options
authorVasant Hegde <hegdevasant@linux.vnet.ibm.com>2020-08-20 11:48:44 +0530
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-08-26 10:31:06 +0200
commitfa80b284d706f445e353255db0f943e9b4b797cc (patch)
parent405ef1b43a3d837e50b30b5164a5cab815931d66 (diff)
powerpc/pseries: Do not initiate shutdown when system is running on UPS
commit 90a9b102eddf6a3f987d15f4454e26a2532c1c98 upstream. As per PAPR we have to look for both EPOW sensor value and event modifier to identify the type of event and take appropriate action. In LoPAPR v1.1 section 10.2.2 includes table 136 "EPOW Action Codes": SYSTEM_SHUTDOWN 3 The system must be shut down. An EPOW-aware OS logs the EPOW error log information, then schedules the system to be shut down to begin after an OS defined delay internal (default is 10 minutes.) Then in section there is table 146 "Platform Event Log Format, Version 6, EPOW Section", which includes the "EPOW Event Modifier": For EPOW sensor value = 3 0x01 = Normal system shutdown with no additional delay 0x02 = Loss of utility power, system is running on UPS/Battery 0x03 = Loss of system critical functions, system should be shutdown 0x04 = Ambient temperature too high All other values = reserved We have a user space tool (rtas_errd) on LPAR to monitor for EPOW_SHUTDOWN_ON_UPS. Once it gets an event it initiates shutdown after predefined time. It also starts monitoring for any new EPOW events. If it receives "Power restored" event before predefined time it will cancel the shutdown. Otherwise after predefined time it will shutdown the system. Commit 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") changed our handling of the "on UPS/Battery" case, to immediately shutdown the system. This breaks existing setups that rely on the userspace tool to delay shutdown and let the system run on the UPS. Fixes: 79872e35469b ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> [mpe: Massage change log and add PAPR references] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200820061844.306460-1-hegdevasant@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c
index e81a285f3a6c..e827108680f2 100644
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -118,7 +118,6 @@ static void handle_system_shutdown(char event_modifier)
pr_emerg("Loss of system power detected. System is running on"
" UPS/battery. Check RTAS error log for details\n");
- orderly_poweroff(true);