# SPDX-License-Identifier: GPL-2.0-only menuconfig RAS bool "Reliability, Availability and Serviceability (RAS) features" help Reliability, availability and serviceability (RAS) is a computer hardware engineering term. Computers designed with higher levels of RAS have a multitude of features that protect data integrity and help them stay available for long periods of time without failure. Reliability can be defined as the probability that the system will produce correct outputs up to some given time. Reliability is enhanced by features that help to avoid, detect and repair hardware faults. Availability is the probability a system is operational at a given time, i.e. the amount of time a device is actually operating as the percentage of total time it should be operating. Serviceability or maintainability is the simplicity and speed with which a system can be repaired or maintained; if the time to repair a failed system increases, then availability will decrease. Note that Reliability and Availability are distinct concepts: Reliability is a measure of the ability of a system to function correctly, including avoiding data corruption, whereas Availability measures how often it is available for use, even though it may not be functioning correctly. For example, a server may run forever and so have ideal availability, but may be unreliable, with frequent data corruption. if RAS config RAS_CEC bool "Correctable Errors Collector" depends on X86_MCE && MEMORY_FAILURE && DEBUG_FS help This is a small cache which collects correctable memory errors per 4K page PFN and counts their repeated occurrence. Once the counter for a PFN overflows, we try to soft-offline that page as we take it to mean that it has reached a relatively high error count and would probably be best if we don't use it anymore. Bear in mind that this is absolutely useless if your platform doesn't have ECC DIMMs and doesn't have DRAM ECC checking enabled in the BIOS. config RAS_CEC_DEBUG bool "CEC debugging machinery" default n depends on RAS_CEC help Add extra files to (debugfs)/ras/cec to test the correctable error collector feature. "pfn" is a writable file that allows user to simulate an error in a particular page frame. "array" is a read-only file that dumps out the current state of all pages logged so far. source "drivers/ras/amd/atl/Kconfig" config RAS_FMPM tristate "FRU Memory Poison Manager" default m depends on AMD_ATL && ACPI_APEI help Support saving and restoring memory error information across reboot using ACPI ERST as persistent storage. Error information is saved with the UEFI CPER "FRU Memory Poison" section format. Memory will be retired during boot time and run time depending on platform-specific policies. endif