[PATCH V17 00/11] 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.

V17:Rebase on tip
    Change trace event helper function names
    Remove unneeded prefixes from commit text

V16:Rebase on 4.11
    Change helper functions from #defines to inline functions
    Address checkpatch warnings which make sense
    Various parameter/variable name changes and spacing changes for better code readibility
    Comment why only GHESv2 needs to acknowledge the error records
    Define and set error structures on the same line
    Change timestamp printing function name to cper_print_tstamp
    Update timestamp to be a single print again and specify when it's precise or imprecise
    Only print section length when the length check fails in the ARM CPER record parsing
    Remove version and length print of ARM error info structures
    Spell out Multiprocessor Affinity Register (MPIDR) and Power State Coordination Interface (PSCI)
    Combine invalid context prints for ARM context info parsing
    Only print register context type as a string
    ifdef around the CPER ARM code to fix x86 compilation failure and remove the enabled check from the if statement
    Use BIT() for CPER ARM #defines
    Only call nmi_enter/exit when interrupts are enabled
    Move GHES panic code into a single function
    Add trace function prototypes in ras.c/ras.h to avoid ifdefs
    Change UUID definition to guarantee we don't overflow the u8 array
    Comment what ghes_notify_sea return means

V15:Rebase on 4.11-rc7
    Use wrapper functions for [un]mapping kernel acknowledgment register
    Spacing and name changes to make code cleaner
    Break up timestamp print to be more readable
    Break generic error data v3 structure handling code into separate patch
     and have timestamp handling in it's own patch
    Put ARM CPER handling into ifdef for ARM systems
    Add braces and missing space to KVM patch

V14:Make sure function prototypes are in the __ASSEMBLY__ block
    Change is_abort_synchronous to is_abort_sea
    Use phys_addr_t for SEA address
    Return after successful SEA handling in handle_guest_abort()

V13:Rebase on 4.11rc2
    Print decimal and hex sizes for unknown CPER section errors
    Use proper CONFIG_* when using IS_ENABLED
    Move handle_guest_sea call prior to SEI check
    Add a return value to handle_guest_sea
    Move RCU locking into ghes_notify_sea
    Add valid bit checks to ARM trace event
    Remove GPIO, SEI, and GSIV cases in GHES
    Add ARCH_HAVE_NMI_SAFE_CMPXCHG since we added NMI usage

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
    Change HAVE_ACPI_APEI_SEA to ACPI_APEI_SEA in KVM SEA case

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
    Make ACPI_APEI_SEA depend on ACPI_APEI_GHES
    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
     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 (10):
  acpi: apei: read ack upon ghes record consumption
  ras: acpi/apei: cper: add support for generic data v3 structure
  cper: add timestamp print to CPER status printing
  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/arm64/Kconfig                   |   2 +
 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                |  80 +++++++++++--
 drivers/acpi/apei/Kconfig            |  15 +++
 drivers/acpi/apei/ghes.c             | 212 +++++++++++++++++++++++++++++------
 drivers/acpi/apei/hest.c             |   7 +-
 drivers/firmware/efi/cper.c          | 204 ++++++++++++++++++++++++++++++---
 drivers/ras/ras.c                    |  16 ++-
 include/acpi/ghes.h                  |  48 +++++++-
 include/linux/cper.h                 |  54 +++++++++
 include/linux/ras.h                  |  15 +++
 include/ras/ras_event.h              |  90 +++++++++++++++
 include/uapi/linux/uuid.h            |   6 +-
 virt/kvm/arm/mmu.c                   |  36 +++++-
 18 files changed, 743 insertions(+), 70 deletions(-)

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