APEI ERST firmware interface and implementation has no multiple users
in mind. For example, if there is four records in storage with ID: 1,
2, 3 and 4, if two ERST readers enumerate the records via
GET_NEXT_RECORD_ID as follow,
reader 1 reader 2
1
2
3
4
-1
-1
where -1 signals there is no more record ID.
Reader 1 has no chance to check record 2 and 4, while reader 2 has no
chance to check record 1 and 3. And any other GET_NEXT_RECORD_ID will
return -1, that is, other readers will has no chance to check any
record even they are not cleared by anyone.
This makes raw GET_NEXT_RECORD_ID not suitable for used by multiple
users.
To solve the issue, an in-memory ERST record ID cache is designed and
implemented. When enumerating record ID, the ID returned by
GET_NEXT_RECORD_ID is added into cache in addition to be returned to
caller. So other readers can check the cache to get all record ID
available.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Move the evaluation of acpi_pci_osc_control_set() (to request control of
PCI Express native features) into acpi_pci_root_add() to avoid calling
it many times for the same root complex with the same arguments.
Additionally, check if all of the requisite _OSC support bits are set
before calling acpi_pci_osc_control_set() for a given root complex.
References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-by: Ozan Caglayan <ozan@pardus.org.tr>
Tested-by: Ozan Caglayan <ozan@pardus.org.tr>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
ERST is a way provided by APEI to save and retrieve hardware error
record to and from some simple persistent storage (such as flash).
The Linux kernel support implementation is quite simple and workable
in NMI context. So it can be used to save hardware error record into
flash in hardware error exception or NMI handler, where other more
complex persistent storage such as disk is not usable. After saving
hardware error records via ERST in hardware error exception or NMI
handler, the error records can be retrieved and logged into disk or
network after a clean reboot.
For more information about ERST, please refer to ACPI Specification
version 4.0, section 17.4.
This patch incorporate fixes from Jin Dongming.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
CC: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Len Brown <len.brown@intel.com>
HEST describes error sources in detail; communicating operational
parameters (i.e. severity levels, masking bits, and threshold values)
to OS as necessary. It also allows the platform to report error
sources for which OS would typically not implement support (for
example, chipset-specific error registers).
HEST information may be needed by other subsystems. For example, HEST
PCIE AER error source information describes whether a PCIE root port
works in "firmware first" mode, this is needed by general PCIE AER
error subsystem. So a public HEST tabling parsing interface is
provided.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
