[PATCH V3 00/10] Add UEFI 2.6 and ACPI 6.1 updates for RAS on ARM64

[Tyler Baicar]

When a memory error, CPU error, PCIe error, or other type of hardware error
that's covered by RAS occurs, firmware should populate the shared GHES memory
location with the proper GHES structures to notify the OS of the error.
For example, platforms that implement firmware first handling may implement
separate GHES sources for corrected errors and uncorrected errors. If the
error is an uncorrectable error, then the firmware will notify the OS
immediately since the error needs to be handled ASAP. The OS will then be able
to take the appropriate action needed such as offlining a page. If the error
is a corrected error, then the firmware will not interrupt the OS immediately.
Instead, the OS will see and report the error the next time it's GHES timer
expires. The kernel will first parse the GHES structures and report the errors
through the kernel logs and then notify the user space through RAS trace
events. This allows user space applications such as RAS Daemon to see the
errors and report them however the user desires. This patchset extends the
kernel functionality for RAS errors based on updates in the UEFI 2.6 and
ACPI 6.1 specifications.

An example flow from firmware to user space could be:

                 +---------------+
       +-------->|               |
       |         |  GHES polling |--+
+-------------+  |    source     |  |   +---------------+   +------------+
|             |  +---------------+  |   |  Kernel GHES  |   |            |
|  Firmware   |                     +-->|  CPER AER and |-->|  RAS trace |
|             |  +---------------+  |   |  EDAC drivers |   |   event    |
+-------------+  |               |  |   +---------------+   +------------+
       |         |  GHES sci     |--+
       +-------->|   source      |
                 +---------------+

Add support for Generic Hardware Error Source (GHES) v2, which introduces the
capability for the OS to acknowledge the consumption of the error record
generated by the Reliability, Availability and Serviceability (RAS) controller.
This eliminates potential race conditions between the OS and the RAS controller.

Add support for the timestamp field added to the Generic Error Data Entry v3,
allowing the OS to log the time that the error is generated by the firmware,
rather than the time the error is consumed. This improves the correctness of
event sequences when analyzing error logs. The timestamp is added in
ACPI 6.1, reference Table 18-343 Generic Error Data Entry.

Add support for ARMv8 Common Platform Error Record (CPER) per UEFI 2.6
specification. ARMv8 specific processor error information is reported as part of
the CPER records.  This provides more detail on for processor error logs. This
can help describe ARMv8 cache, tlb, and bus errors.

Synchronous External Abort (SEA) represents a specific processor error condition
in ARM systems. A handler is added to recognize SEA errors, and a notifier is
added to parse and report the errors before the process is killed. Refer to
section N.2.1.1 in the Common Platform Error Record appendix of the UEFI 2.6
specification.

Currently the kernel ignores CPER records that are unrecognized.
On the other hand, UEFI spec allows for non-standard (eg. vendor
proprietary) error section type in CPER (Common Platform Error Record),
as defined in section N2.3 of UEFI version 2.5. Therefore, user
is not able to see hardware error data of non-standard section.

If section Type field of Generic Error Data Entry is unrecognized,
prints out the raw data in dmesg buffer, and also adds a tracepoint
for reporting such hardware errors.

Currently even if an error status block's severity is fatal, the kernel
does not honor the severity level and panic. With the firmware first
model, the platform could inform the OS about a fatal hardware error
through the non-NMI GHES notification type. The OS should panic when a
hardware error record is received with this severity.

Add support to handle SEAs that occur while a KVM guest kernel is
running. Currently these are unsupported by the guest abort handling.

Depends on: [PATCH v14] acpi, apei, arm64: APEI initial support for aarch64.
            https://lkml.org/lkml/2016/8/10/231

V3: Fix unmapped address to the read_ack_register in ghes.c
    Add helper function to get the proper payload based on generic data entry
     version
    Move timestamp print to avoid changing function calls in cper.c
    Remove patch "arm64: exception: handle instruction abort at current EL"
     since the el1_ia handler is already added in 4.8
    Add EFI and ARM64 dependencies for HAVE_ACPI_APEI_SEA
    Add a new trace event for ARM type errors
    Add support to handle KVM guest SEAs

V2: Add PSCI state print for the ARMv8 error type.
    Separate timestamp year into year and century using BCD format.
    Rebase on top of ACPICA 20160318 release and remove header file changes
     in include/acpi/actbl1.h.
    Add panic OS with fatal error status block patch.
    Add processing of unrecognized CPER error section patches with updates
     from previous comments. Original patches: https://lkml.org/lkml/2015/9/8/646

V1: https://lkml.org/lkml/2016/2/5/544

Jonathan (Zhixiong) Zhang (1):
  acpi: apei: panic OS with fatal error status block

Tyler Baicar (9):
  acpi: apei: read ack upon ghes record consumption
  ras: acpi/apei: cper: generic error data entry v3 per ACPI 6.1
  efi: parse ARMv8 processor error
  arm64: exception: handle Synchronous External Abort
  acpi: apei: handle SEA notification type for ARMv8
  efi: print unrecognized CPER section
  ras: acpi / apei: generate trace event for unrecognized CPER section
  trace, ras: add ARM processor error trace event
  arm64: KVM: add guest SEA support

 arch/arm/include/asm/kvm_arm.h       |   1 +
 arch/arm/include/asm/system_misc.h   |   5 +
 arch/arm/kvm/mmu.c                   |  15 ++-
 arch/arm64/Kconfig                   |   1 +
 arch/arm64/include/asm/kvm_arm.h     |   1 +
 arch/arm64/include/asm/system_misc.h |  15 +++
 arch/arm64/mm/fault.c                |  71 ++++++++--
 drivers/acpi/apei/Kconfig            |  15 +++
 drivers/acpi/apei/ghes.c             | 177 +++++++++++++++++++++++-
 drivers/acpi/apei/hest.c             |   7 +-
 drivers/firmware/efi/cper.c          | 252 ++++++++++++++++++++++++++++++++---
 drivers/ras/ras.c                    |   2 +
 include/acpi/ghes.h                  |   1 +
 include/linux/cper.h                 |  72 ++++++++++
 include/ras/ras_event.h              | 112 ++++++++++++++++
 15 files changed, 711 insertions(+), 36 deletions(-)

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.