Documentation / acpi / apei / einj.txt
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Based on kernel version 3.3. Page generated on 2012-03-23 21:23 EST.
1 APEI Error INJection 2 ~~~~~~~~~~~~~~~~~~~~ 3 4 EINJ provides a hardware error injection mechanism 5 It is very useful for debugging and testing of other APEI and RAS features. 6 7 To use EINJ, make sure the following are enabled in your kernel 8 configuration: 9 10 CONFIG_DEBUG_FS 11 CONFIG_ACPI_APEI 12 CONFIG_ACPI_APEI_EINJ 13 14 The user interface of EINJ is debug file system, under the 15 directory apei/einj. The following files are provided. 16 17 - available_error_type 18 Reading this file returns the error injection capability of the 19 platform, that is, which error types are supported. The error type 20 definition is as follow, the left field is the error type value, the 21 right field is error description. 22 23 0x00000001 Processor Correctable 24 0x00000002 Processor Uncorrectable non-fatal 25 0x00000004 Processor Uncorrectable fatal 26 0x00000008 Memory Correctable 27 0x00000010 Memory Uncorrectable non-fatal 28 0x00000020 Memory Uncorrectable fatal 29 0x00000040 PCI Express Correctable 30 0x00000080 PCI Express Uncorrectable fatal 31 0x00000100 PCI Express Uncorrectable non-fatal 32 0x00000200 Platform Correctable 33 0x00000400 Platform Uncorrectable non-fatal 34 0x00000800 Platform Uncorrectable fatal 35 36 The format of file contents are as above, except there are only the 37 available error type lines. 38 39 - error_type 40 This file is used to set the error type value. The error type value 41 is defined in "available_error_type" description. 42 43 - error_inject 44 Write any integer to this file to trigger the error 45 injection. Before this, please specify all necessary error 46 parameters. 47 48 - param1 49 This file is used to set the first error parameter value. Effect of 50 parameter depends on error_type specified. 51 52 - param2 53 This file is used to set the second error parameter value. Effect of 54 parameter depends on error_type specified. 55 56 BIOS versions based in the ACPI 4.0 specification have limited options 57 to control where the errors are injected. Your BIOS may support an 58 extension (enabled with the param_extension=1 module parameter, or 59 boot command line einj.param_extension=1). This allows the address 60 and mask for memory injections to be specified by the param1 and 61 param2 files in apei/einj. 62 63 BIOS versions using the ACPI 5.0 specification have more control over 64 the target of the injection. For processor related errors (type 0x1, 65 0x2 and 0x4) the APICID of the target should be provided using the 66 param1 file in apei/einj. For memory errors (type 0x8, 0x10 and 0x20) 67 the address is set using param1 with a mask in param2 (0x0 is equivalent 68 to all ones). For PCI express errors (type 0x40, 0x80 and 0x100) the 69 segment, bus, device and function are specified using param1: 70 71 31 24 23 16 15 11 10 8 7 0 72 +-------------------------------------------------+ 73 | segment | bus | device | function | reserved | 74 +-------------------------------------------------+ 75 76 An ACPI 5.0 BIOS may also allow vendor specific errors to be injected. 77 In this case a file named vendor will contain identifying information 78 from the BIOS that hopefully will allow an application wishing to use 79 the vendor specific extension to tell that they are running on a BIOS 80 that supports it. All vendor extensions have the 0x80000000 bit set in 81 error_type. A file vendor_flags controls the interpretation of param1 82 and param2 (1 = PROCESSOR, 2 = MEMORY, 4 = PCI). See your BIOS vendor 83 documentation for details (and expect changes to this API if vendors 84 creativity in using this feature expands beyond our expectations). 85 86 Example: 87 # cd /sys/kernel/debug/apei/einj 88 # cat available_error_type # See which errors can be injected 89 0x00000002 Processor Uncorrectable non-fatal 90 0x00000008 Memory Correctable 91 0x00000010 Memory Uncorrectable non-fatal 92 # echo 0x12345000 > param1 # Set memory address for injection 93 # echo 0xfffffffffffff000 > param2 # Mask - anywhere in this page 94 # echo 0x8 > error_type # Choose correctable memory error 95 # echo 1 > error_inject # Inject now 96 97 98 For more information about EINJ, please refer to ACPI specification 99 version 4.0, section 17.5 and ACPI 5.0, section 18.6.
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