In the firmware-first RAS solution, corrupt data is detected in a memory location when guest OS application software executing at EL0 or guest OS kernel El1 software are reading from the memory. The memory node records errors in an error record accessible using system registers. Because SCR_EL3.EA is 1, then CPU will trap to El3 firmware, EL3 firmware records the error to APEI table through reading system register. Because the error was taken from a lower Exception leve, if the exception is SEA/SEI and HCR_EL2.TEA/HCR_EL2.AMO is 1, firmware sets ESR_EL2/FAR_El to fake a exception trap to EL2, then transfers to hypervisor. Hypervisor calls the momory failure to deal with this error, momory failure read the APEI table and decide whether it needs to deliver SIGBUS signal to user space, the advantage of using SIGBUS signal to notify user space is that it can be compatible Non-Kvm users. Dongjiu Geng (5): acpi: apei: Add SEI notification type support for ARMv8 support user space to query RAS extension feature arm64: kvm: route synchronous external abort exceptions to el2 KVM: arm/arm64: Allow get exception syndrome and arm64: kvm: handle SEI notification and inject virtual SError James Morse (1): KVM: arm64: Save ESR_EL2 on guest SError Xie XiuQi (1): arm64: cpufeature: Detect CPU RAS Extentions arch/arm/include/asm/kvm_host.h | 2 ++ arch/arm/kvm/guest.c | 5 +++ arch/arm64/Kconfig | 16 ++++++++++ arch/arm64/include/asm/barrier.h | 1 + arch/arm64/include/asm/cpucaps.h | 3 +- arch/arm64/include/asm/kvm_arm.h | 2 ++ arch/arm64/include/asm/kvm_emulate.h | 17 ++++++++++ arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/include/asm/sysreg.h | 5 +++ arch/arm64/include/asm/system_misc.h | 1 + arch/arm64/include/uapi/asm/kvm.h | 5 +++ arch/arm64/kernel/cpufeature.c | 13 ++++++++ arch/arm64/kernel/process.c | 3 ++ arch/arm64/kvm/guest.c | 48 +++++++++++++++++++++++++++++ arch/arm64/kvm/handle_exit.c | 21 +++++++++++-- arch/arm64/kvm/hyp/switch.c | 29 +++++++++++++++-- arch/arm64/kvm/reset.c | 3 ++ arch/arm64/mm/fault.c | 21 +++++++++++-- drivers/acpi/apei/Kconfig | 15 +++++++++ drivers/acpi/apei/ghes.c | 60 +++++++++++++++++++++++------------- include/acpi/ghes.h | 2 +- include/uapi/linux/kvm.h | 3 ++ virt/kvm/arm/arm.c | 7 +++++ 23 files changed, 254 insertions(+), 30 deletions(-) -- 2.14.0
