linux.git/include/ras, branch v6.18.21

RAS: Report all ARM processor CPER information to userspace

2025-12-18T13:03:09+00:00

[ Upstream commit 05954511b73e748d0370549ad9dd9cd95297d97a ]

The ARM processor CPER record was added in UEFI v2.6 and remained
unchanged up to v2.10.

Yet, the original arm_event trace code added by

  e9279e83ad1f ("trace, ras: add ARM processor error trace event")

is incomplete, as it only traces some fields of UAPI 2.6 table N.16, not
exporting any information from tables N.17 to N.29 of the record.

This is not enough for the user to be able to figure out what has
exactly happened or to take appropriate action.

According to the UEFI v2.9 specification chapter N2.4.4, the ARM
processor error section includes:

- several (ERR_INFO_NUM) ARM processor error information structures
  (Tables N.17 to N.20);
- several (CONTEXT_INFO_NUM) ARM processor context information
  structures (Tables N.21 to N.29);
- several vendor specific error information structures. The
  size is given by Section Length minus the size of the other
  fields.

In addition, it also exports two fields that are parsed by the GHES
driver when firmware reports it, e.g.:

- error severity
- CPU logical index

Report all of these information to userspace via a the ARM tracepoint so
that userspace can properly record the error and take decisions related
to CPU core isolation according to error severity and other info.

The updated ARM trace event now contains the following fields:

======================================  =============================
UEFI field on table N.16                ARM Processor trace fields
======================================  =============================
Validation                              handled when filling data for
                                        affinity MPIDR and running
                                        state.
ERR_INFO_NUM                            pei_len
CONTEXT_INFO_NUM                        ctx_len
Section Length                          indirectly reported by
                                        pei_len, ctx_len and oem_len
Error affinity level                    affinity
MPIDR_EL1                               mpidr
MIDR_EL1                                midr
Running State                           running_state
PSCI State                              psci_state
Processor Error Information Structure   pei_err - count at pei_len
Processor Context                       ctx_err- count at ctx_len
Vendor Specific Error Info              oem - count at oem_len
======================================  =============================

It should be noted that decoding of tables N.17 to N.29, if needed, will
be handled in userspace. That gives more flexibility, as there won't be
any need to flood the kernel with micro-architecture specific error
decoding.

Also, decoding the other fields require a complex logic, and should be
done for each of the several values inside the record field.  So, let
userspace daemons like rasdaemon decode them, parsing such tables and
having vendor-specific micro-architecture-specific decoders.

 [mchehab: modified description, solved merge conflicts and fixed coding style]

Signed-off-by: Jason Tian 
Co-developed-by: Shengwei Luo 
Signed-off-by: Shengwei Luo 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Daniel Ferguson  # rebased
Reviewed-by: Jonathan Cameron 
Tested-by: Shiju Jose 
Acked-by: Borislav Petkov (AMD) 
Fixes: e9279e83ad1f ("trace, ras: add ARM processor error trace event")
Link: https://uefi.org/specs/UEFI/2.10/Apx_N_Common_Platform_Error_Record.html#arm-processor-error-section
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Sasha Levin

tracing, AER: Hide PCIe AER event when PCIEAER is not configured

2025-07-21T20:40:56+00:00

The event aer_event is only used when CONFIG_PCIEAER is configured. It
should not be created when it is not. When an event is created it creates
around 5K of text and meta data regardless if the tracepoint is used or
not. Instead of wasting this memory, put #ifdef around the event to not
create it when it is not used.

Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Cc: Tony Luck 
Link: https://lore.kernel.org/20250612094932.4a08abd6@batman.local.home
Acked-by: Borislav Petkov (AMD) 
Signed-off-by: Steven Rostedt (Google)

PCI/ERR: Handle TLP Log in Flit mode

2025-02-21T23:31:45+00:00

Flit mode introduced in PCIe r6.0 alters how the TLP Header Log is
presented through AER and DPC Capability registers. The TLP Prefix Log
Register is not present with Flit mode, and the register becomes an
extension of the TLP Header Log (PCIe r6.1 secs 7.8.4.12 & 7.9.14.13).

Adapt pcie_read_tlp_log() and struct pcie_tlp_log to read and store the
extended TLP Header Log when the Link is in Flit mode. As the Prefix Log
and Extended TLP Header are not present at the same time, a C union can be
used.

Determining whether the error occurred while the Link was in Flit mode is a
bit complicated. In case of AER, the Advanced Error Capabilities and
Control Register directly tells whether the error was logged in Flit mode
or not (PCIe r6.1 sec 7.8.4.7). The DPC Capability (PCIe r6.1 sec 7.9.14),
unfortunately, does not contain the same information.

Unlike AER, the DPC Capability does not provide a way to discern whether
the error was logged in Flit mode (this is confirmed by PCI WG to be an
oversight in the spec). DPC will bring the Link down immediately following
an error, which makes it impossible to acquire the Flit Mode Status
directly from the Link Status 2 register because Flit Mode Status is only
set in certain Link states (PCIe r6.1 sec 7.5.3.20). As a workaround, use
the flit_mode value stored into the struct pci_bus.

Link: https://lore.kernel.org/r/20250207161836.2755-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen 
Signed-off-by: Bjorn Helgaas

mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND

2024-07-12T22:52:22+00:00

The page cannot become compound pages again just after a folio is split as
an extra refcnt is held.  So the MF_MSG_DIFFERENT_COMPOUND case is
obsolete and can be removed to get rid of this false assumption and code
burden.  But add one WARN_ON() here to keep the situation clear.

Link: https://lkml.kernel.org/r/20240708030544.196919-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin 
Cc: Borislav Petkov (AMD) 
Cc: Naoya Horiguchi 
Cc: Tony Luck 
Signed-off-by: Andrew Morton

mm/memory-failure: remove MF_MSG_SLAB

2024-07-04T02:30:10+00:00

Since commit 46df8e73a4a3 ("mm: free up PG_slab"), MF_MSG_SLAB becomes
unused.  Remove it.  No functional change intended.

Link: https://lkml.kernel.org/r/20240612071835.157004-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin 
Cc: Borislav Petkov (AMD) 
Cc: David Hildenbrand 
Cc: kernel test robot 
Cc: Naoya Horiguchi 
Cc: Tony Luck 
Signed-off-by: Andrew Morton

mm/memory-failure: improve memory failure action_result messages

2024-07-04T02:29:57+00:00

Added two explicit MF_MSG messages describing failure in
get_hwpoison_page.  Attemped to document the definition of various action
names, and made a few adjustment to the action_result() calls.

Link: https://lkml.kernel.org/r/20240524215306.2705454-4-jane.chu@oracle.com
Signed-off-by: Jane Chu 
Reviewed-by: Oscar Salvador 
Acked-by: Miaohe Lin 
Cc: Naoya Horiguchi 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton

tracing/treewide: Remove second parameter of __assign_str()

2024-05-23T00:14:47+00:00

With the rework of how the __string() handles dynamic strings where it
saves off the source string in field in the helper structure[1], the
assignment of that value to the trace event field is stored in the helper
value and does not need to be passed in again.

This means that with:

  __string(field, mystring)

Which use to be assigned with __assign_str(field, mystring), no longer
needs the second parameter and it is unused. With this, __assign_str()
will now only get a single parameter.

There's over 700 users of __assign_str() and because coccinelle does not
handle the TRACE_EVENT() macro I ended up using the following sed script:

  git grep -l __assign_str | while read a ; do
      sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file;
      mv /tmp/test-file $a;
  done

I then searched for __assign_str() that did not end with ';' as those
were multi line assignments that the sed script above would fail to catch.

Note, the same updates will need to be done for:

  __assign_str_len()
  __assign_rel_str()
  __assign_rel_str_len()

I tested this with both an allmodconfig and an allyesconfig (build only for both).

[1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/

Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home

Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Cc: Linus Torvalds 
Cc: Julia Lawall 
Signed-off-by: Steven Rostedt (Google) 
Acked-by: Jani Nikula 
Acked-by: Christian König  for the amdgpu parts.
Acked-by: Thomas Hellström  #for
Acked-by: Rafael J. Wysocki  # for thermal
Acked-by: Takashi Iwai 
Acked-by: Darrick J. Wong 	# xfs
Tested-by: Guenter Roeck

PCI/AER: Generalize TLP Header Log reading

2024-03-08T21:26:46+00:00

Both AER and DPC RP PIO provide TLP Header Log registers (PCIe r6.1 secs
7.8.4 & 7.9.14) to convey error diagnostics but the struct is named after
AER as the struct aer_header_log_regs. Also, not all places that handle TLP
Header Log use the struct and the struct members are named individually.

Generalize the struct name and members, and use it consistently where TLP
Header Log is being handled so that a pcie_read_tlp_log() helper can be
easily added.

Link: https://lore.kernel.org/r/20240206135717.8565-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen 
[bhelgaas: drop ixgbe changes for now, tidy whitespace]
Signed-off-by: Bjorn Helgaas

mm, hwpoison: enable memory error handling on 1GB hugepage

2022-08-09T01:06:44+00:00

Now error handling code is prepared, so remove the blocking code and
enable memory error handling on 1GB hugepage.

Link: https://lkml.kernel.org/r/20220714042420.1847125-9-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi 
Reviewed-by: Miaohe Lin 
Cc: David Hildenbrand 
Cc: kernel test robot 
Cc: Liu Shixin 
Cc: Mike Kravetz 
Cc: Muchun Song 
Cc: Oscar Salvador 
Cc: Yang Shi 
Signed-off-by: Andrew Morton

Revert "mm/memory-failure.c: fix race with changing page compound again"

2022-04-29T06:16:02+00:00

Reverts commit 888af2701db7 ("mm/memory-failure.c: fix race with changing
page compound again") because now we fetch the page refcount under
hugetlb_lock in try_memory_failure_hugetlb() so that the race check is no
longer necessary.

Link: https://lkml.kernel.org/r/20220408135323.1559401-4-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi 
Suggested-by: Miaohe Lin 
Reviewed-by: Miaohe Lin 
Reviewed-by: Mike Kravetz 
Cc: Miaohe Lin 
Cc: Yang Shi 
Cc: Dan Carpenter 
Signed-off-by: Andrew Morton