- APEI Error INJection
- ~~~~~~~~~~~~~~~~~~~~
+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+APEI Error INJection
+====================
EINJ provides a hardware error injection mechanism. It is very useful
for debugging and testing APEI and RAS features in general.
You need to check whether your BIOS supports EINJ first. For that, look
-for early boot messages similar to this one:
+for early boot messages similar to this one::
-ACPI: EINJ 0x000000007370A000 000150 (v01 INTEL 00000001 INTL 00000001)
+ ACPI: EINJ 0x000000007370A000 000150 (v01 INTEL 00000001 INTL 00000001)
which shows that the BIOS is exposing an EINJ table - it is the
mechanism through which the injection is done.
the BIOS menu.
To use EINJ, make sure the following are options enabled in your kernel
-configuration:
+configuration::
-CONFIG_DEBUG_FS
-CONFIG_ACPI_APEI
-CONFIG_ACPI_APEI_EINJ
+ CONFIG_DEBUG_FS
+ CONFIG_ACPI_APEI
+ CONFIG_ACPI_APEI_EINJ
The EINJ user interface is in <debugfs mount point>/apei/einj.
This file shows which error types are supported:
+ ================ ===================================
Error Type Value Error Description
- ================ =================
- 0x00000001 Processor Correctable
- 0x00000002 Processor Uncorrectable non-fatal
- 0x00000004 Processor Uncorrectable fatal
- 0x00000008 Memory Correctable
- 0x00000010 Memory Uncorrectable non-fatal
- 0x00000020 Memory Uncorrectable fatal
- 0x00000040 PCI Express Correctable
- 0x00000080 PCI Express Uncorrectable fatal
- 0x00000100 PCI Express Uncorrectable non-fatal
- 0x00000200 Platform Correctable
- 0x00000400 Platform Uncorrectable non-fatal
- 0x00000800 Platform Uncorrectable fatal
+ ================ ===================================
+ 0x00000001 Processor Correctable
+ 0x00000002 Processor Uncorrectable non-fatal
+ 0x00000004 Processor Uncorrectable fatal
+ 0x00000008 Memory Correctable
+ 0x00000010 Memory Uncorrectable non-fatal
+ 0x00000020 Memory Uncorrectable fatal
+ 0x00000040 PCI Express Correctable
+ 0x00000080 PCI Express Uncorrectable fatal
+ 0x00000100 PCI Express Uncorrectable non-fatal
+ 0x00000200 Platform Correctable
+ 0x00000400 Platform Uncorrectable non-fatal
+ 0x00000800 Platform Uncorrectable fatal
+ ================ ===================================
The format of the file contents are as above, except present are only
the available error types.
injection. Value is a bitmask as specified in ACPI5.0 spec for the
SET_ERROR_TYPE_WITH_ADDRESS data structure:
- Bit 0 - Processor APIC field valid (see param3 below).
- Bit 1 - Memory address and mask valid (param1 and param2).
- Bit 2 - PCIe (seg,bus,dev,fn) valid (see param4 below).
+ Bit 0
+ Processor APIC field valid (see param3 below).
+ Bit 1
+ Memory address and mask valid (param1 and param2).
+ Bit 2
+ PCIe (seg,bus,dev,fn) valid (see param4 below).
If set to zero, legacy behavior is mimicked where the type of
injection specifies just one bit set, and param1 is multiplexed.
the target of the injection. For processor-related errors (type 0x1, 0x2
and 0x4), you can set flags to 0x3 (param3 for bit 0, and param1 and
param2 for bit 1) so that you have more information added to the error
-signature being injected. The actual data passed is this:
+signature being injected. The actual data passed is this::
memory_address = param1;
memory_address_range = param2;
For memory errors (type 0x8, 0x10 and 0x20) the address is set using
param1 with a mask in param2 (0x0 is equivalent to all ones). For PCI
express errors (type 0x40, 0x80 and 0x100) the segment, bus, device and
-function are specified using param1:
+function are specified using param1::
31 24 23 16 15 11 10 8 7 0
+-------------------------------------------------+
creativity in using this feature expands beyond our expectations).
-An error injection example:
+An error injection example::
-# cd /sys/kernel/debug/apei/einj
-# cat available_error_type # See which errors can be injected
-0x00000002 Processor Uncorrectable non-fatal
-0x00000008 Memory Correctable
-0x00000010 Memory Uncorrectable non-fatal
-# echo 0x12345000 > param1 # Set memory address for injection
-# echo $((-1 << 12)) > param2 # Mask 0xfffffffffffff000 - anywhere in this page
-# echo 0x8 > error_type # Choose correctable memory error
-# echo 1 > error_inject # Inject now
+ # cd /sys/kernel/debug/apei/einj
+ # cat available_error_type # See which errors can be injected
+ 0x00000002 Processor Uncorrectable non-fatal
+ 0x00000008 Memory Correctable
+ 0x00000010 Memory Uncorrectable non-fatal
+ # echo 0x12345000 > param1 # Set memory address for injection
+ # echo $((-1 << 12)) > param2 # Mask 0xfffffffffffff000 - anywhere in this page
+ # echo 0x8 > error_type # Choose correctable memory error
+ # echo 1 > error_inject # Inject now
-You should see something like this in dmesg:
+You should see something like this in dmesg::
-[22715.830801] EDAC sbridge MC3: HANDLING MCE MEMORY ERROR
-[22715.834759] EDAC sbridge MC3: CPU 0: Machine Check Event: 0 Bank 7: 8c00004000010090
-[22715.834759] EDAC sbridge MC3: TSC 0
-[22715.834759] EDAC sbridge MC3: ADDR 12345000 EDAC sbridge MC3: MISC 144780c86
-[22715.834759] EDAC sbridge MC3: PROCESSOR 0:306e7 TIME 1422553404 SOCKET 0 APIC 0
-[22716.616173] EDAC MC3: 1 CE memory read error on CPU_SrcID#0_Channel#0_DIMM#0 (channel:0 slot:0 page:0x12345 offset:0x0 grain:32 syndrome:0x0 - area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:0)
+ [22715.830801] EDAC sbridge MC3: HANDLING MCE MEMORY ERROR
+ [22715.834759] EDAC sbridge MC3: CPU 0: Machine Check Event: 0 Bank 7: 8c00004000010090
+ [22715.834759] EDAC sbridge MC3: TSC 0
+ [22715.834759] EDAC sbridge MC3: ADDR 12345000 EDAC sbridge MC3: MISC 144780c86
+ [22715.834759] EDAC sbridge MC3: PROCESSOR 0:306e7 TIME 1422553404 SOCKET 0 APIC 0
+ [22716.616173] EDAC MC3: 1 CE memory read error on CPU_SrcID#0_Channel#0_DIMM#0 (channel:0 slot:0 page:0x12345 offset:0x0 grain:32 syndrome:0x0 - area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:0)
For more information about EINJ, please refer to ACPI specification
version 4.0, section 17.5 and ACPI 5.0, section 18.6.