In ARM64 hardware platforms, for example our Kunpeng platforms, CPU L1/L2 cache corrected errors are reported in the ARM processor error section. The situations the CPU CE errors are reported too often is not unlikely and may need to isolate that CPU core to prevent leading to more serious faults. This is important for the early fault prediction. Extend the existing RAS CEC to support the errors count check on short time period with the threshold. The decay interval is divided into a number of time slots for these elements. The CEC calculates the average error count for each element at the end of each decay interval. Then the average count would be subtracted from the total count in each of the following time slots within the decay interval. The work function for the decay interval would be set for a reduced time period = decay interval/ number of time slots. When the new CE count for a CPU is added, the element would try to offline when the sum of the most recent CEs counts exceeded the CEs threshold value. More implementation details is added in the file. Add collection of CPU correctable errors, for example ARM64 L1/L2 cache errors and isolation of the CPU core when the errors count in the short time interval exceed the threshold value. Open Questions based on the feedback from Boris, 1. ARM processor error types are cache/TLB/bus errors. [Reference N2.4.4.1 ARM Processor Error Information UEFI Spec v2.8] Any of the above error types should not be consider for the error collection and CPU core isolation? 2.If disabling entire CPU core is not acceptable, please suggest method to disable L1 and L2 cache on ARM64 core? Shiju Jose (7): RAS/CEC: Replace the macro PFN with ELEM_NO RAS/CEC: Replace pfns_poisoned with elems_poisoned RAS/CEC: Move X86 MCE specific code under CONFIG_X86_MCE RAS/CEC: Modify cec_mod_work() for common use RAS/CEC: Add support for errors count check on short time period RAS/CEC: Add CPU Correctable Error Collector to isolate an erroneous CPU core ACPI / APEI: Add reporting ARM64 CPU correctable errors to the CEC arch/arm64/ras/Kconfig | 17 ++ drivers/acpi/apei/ghes.c | 36 +++- drivers/ras/Kconfig | 1 + drivers/ras/cec.c | 399 +++++++++++++++++++++++++++++++++++---- include/linux/ras.h | 9 + 5 files changed, 418 insertions(+), 44 deletions(-) create mode 100644 arch/arm64/ras/Kconfig -- 2.17.1