[PATCH V12 00/10] Add UEFI 2.6 and ACPI 6.1 updates for RAS on ARM64

Tyler Baicar tbaicar at codeaurora.org
Mon Mar 6 12:44:53 PST 2017

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

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.

V12:Remove double quotes from CPER code
    Add helper function to check all SEA cases in KVM patch
    Replace nmi_enter/exit with rcu_read_lock/unlock for KVM SEA

V11:Change print_hex_dump calls to include ASCII output
    Change HAVE_ACPI_APEI_SEA to ACPI_APEI_SEA and make it 'default y'
    Add unknown print back when printing unknown CPER section
    Make sure to use "%s"" in CPER code
    Spacing fix when checking if SEA is enabled

V10:Fix spacing of trace event enabled if statement

V9: Move SEA_FnV_MASK to ESR_ELx_FnV
    Move HAVE_NMI into alphabetical order
    Remove duplicate hardirq.h include
    Only call ghes_notify_sea if HAVE_ACPI_APEI_SEA
    Use phys_addr_t for physical address variable
    Make ghes_sea_add() return void
    Add include guard to ghes.h
    Verify HAVE_RAS before calling ras trace events
    Call __ghes_print_estatus() before __ghes_call_panic()
    Add trace_*_event_enabled() checks for both new trace events

V8: Remove SEA notifier
    Add FAR not valid bit check when populating the SEA error address
    Move nmi_enter/exit() to architecture specific code
    Add synchronize_rcu() usage to SEA handling
    Make GHES_IOREMAP_PAGES always 2
    Update ghes_ioremap_pfn_nmi() to work like ghes_ioremap_pfn_irq()
    Remove the SEA print from handle_guest_sea()

V7: Update a couple prints for ARM processor errors
    Add Print notifying if overflow occurred for ARM processor errors
    Check for ARM configuration to allow the compiler to ignore ARM code
     on non-ARM systems
    Use SEA acronym instead of spelling it out
    Update fault_info prints to be more clear
    Add NMI locking to SEA notification
    Remove error info structure from ARM trace event since there can be
     a variable amount of these structures

V6: Change HEST_TYPE_GENERIC_V2 to IS_HEST_TYPE_GENERIC_V2 for readability
    Move APEI helper defines from cper.h to ghes.h
    Add data_len decrement back into print loop
    Change references to ARMv8 to just ARM
    Rewrite ARM processor context info parsing
    Check valid bit of ARM error info field before printing it
    Add include of linux/uuid.h in ghes.c

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
    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 ARM 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       |  10 ++
 arch/arm/include/asm/system_misc.h   |   5 +
 arch/arm/kvm/mmu.c                   |  36 +++++-
 arch/arm64/Kconfig                   |   1 +
 arch/arm64/include/asm/esr.h         |   1 +
 arch/arm64/include/asm/kvm_arm.h     |  10 ++
 arch/arm64/include/asm/system_misc.h |   2 +
 arch/arm64/mm/fault.c                |  74 +++++++++++--
 drivers/acpi/apei/Kconfig            |  15 +++
 drivers/acpi/apei/ghes.c             | 184 ++++++++++++++++++++++++++----
 drivers/acpi/apei/hest.c             |   7 +-
 drivers/firmware/efi/cper.c          | 209 ++++++++++++++++++++++++++++++++---
 drivers/ras/ras.c                    |   2 +
 include/acpi/ghes.h                  |  34 +++++-
 include/linux/cper.h                 |  54 +++++++++
 include/ras/ras_event.h              |  79 +++++++++++++
 16 files changed, 673 insertions(+), 50 deletions(-)

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