Hi gengdongjiu, On 16/01/18 11:17, gengdongjiu wrote: > Hi James, > > On 2018/1/16 3:38, James Morse wrote: >> From: Xie XiuQi <xiexiuqi@xxxxxxxxxx> >> >> ARM's v8.2 Extentions add support for Reliability, Availability and >> Serviceability (RAS). On CPUs with these extensions system software >> can use additional barriers to isolate errors and determine if faults >> are pending. Add cpufeature detection. >> >> Platform level RAS support may require additional firmware support. >> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >> index 664fadc2aa2e..1d51c8edf34b 100644 >> --- a/arch/arm64/Kconfig >> +++ b/arch/arm64/Kconfig >> @@ -1062,6 +1062,22 @@ config ARM64_PMEM >> operations if DC CVAP is not supported (following the behaviour of >> DC CVAP itself if the system does not define a point of persistence). >> >> +config ARM64_RAS_EXTN >> + bool "Enable support for RAS CPU Extensions" >> + default y >> + help >> + CPUs that support the Reliability, Availability and Serviceability >> + (RAS) Extensions, part of ARMv8.2 are able to track faults and >> + errors, classify them and report them to software. >> + >> + On CPUs with these extensions system software can use additional >> + barriers to determine if faults are pending and read the >> + classification from a new set of registers. >> + >> + Selecting this feature will allow the kernel to use these barriers >> + and access the new registers if the system supports the extension. >> + Platform RAS features may additionally depend on firmware support. >> + >> endmenu >> > it seems this "CONFIG_ARM64_RAS_EXTN" is not enabled in the "arch/arm64/configs/defconfig", > if not, I want to enable this config to enable RAS feature in the defconfig. do you agree? Sure. This series doesn't do a lot on its own, it expects firmware-first or kernel-first support, which may in turn depend-on this feature. It means we don't panic() when notified of corrected errors, until we get the {firmware,kernel}-first support. Don't defconfig changes get collected by arm-soc? (I'm not sure how these get picked up...) James _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm