Re: [PATCH V5 00/10] Add UEFI 2.6 and ACPI 6.1 updates for RAS on ARM64

["Baicar, Tyler" <tbaicar@codeaurora.org>]

Thank you John! Let me know how it goes and if you have any questions :)

Tyler

On 11/22/2016 4:11 AM, John Garry wrote:
> +
>
> We'll try and test this on our platform.
>
> Cheers,
> John
>
> On 21/11/2016 22:35, Tyler Baicar wrote:
>> 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
>>
>> V5: Fix GHES goto logic for error conditions
>>     Change ghes_do_read_ack to ghes_ack_error
>>     Make sure data version check is >= 3
>>     Use CPER helper functions in print functions
>>     Make handle_guest_sea() dummy function static for arm
>>     Add arm to subject line for KVM patch
>>
>> V4: Add bit offset left shift to read_ack_write value
>>     Make HEST generic and generic_v2 structures a union in the ghes 
>> structure
>>     Move gdata v3 helper functions into ghes.h to avoid duplication
>>     Reorder the timestamp print and avoid memcpy
>>     Add helper functions for gdata size checking
>>     Rename the SEA functions
>>     Add helper function for GHES panics
>>     Set fru_id to NULL UUID at variable declaration
>>     Limit ARM trace event parameters to the needed structures
>>     Reorder the ARM trace event variables to save space
>>     Add comment for why we don't pass SEAs to the guest when it aborts
>>     Move ARM trace event call into GHES driver instead of CPER
>>
>> 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
>>   arm/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                   |  18 ++-
>>  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            |  14 +++
>>  drivers/acpi/apei/ghes.c             | 188 
>> ++++++++++++++++++++++++++++---
>>  drivers/acpi/apei/hest.c             |   7 +-
>>  drivers/firmware/efi/cper.c          | 210 
>> ++++++++++++++++++++++++++++++++---
>>  drivers/ras/ras.c                    |   2 +
>>  include/acpi/ghes.h                  |  15 ++-
>>  include/linux/cper.h                 |  84 ++++++++++++++
>>  include/ras/ras_event.h              | 100 +++++++++++++++++
>>  15 files changed, 688 insertions(+), 44 deletions(-)
>>
>
>

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