• Huang Ying's avatar
    ACPI / APEI: Add Boot Error Record Table (BERT) support · a3e2acc5
    Huang Ying authored
    ACPI/APEI is designed to verifiy/report H/W errors, like Corrected
    Error(CE) and Uncorrected Error(UC). It contains four tables: HEST,
    ERST, EINJ and BERT. The first three tables have been merged for
    a long time, but because of lacking BIOS support for BERT, the
    support for BERT is pending until now. Recently on ARM 64 platform
    it is has been supported. So here we come.
    
    Under normal circumstances, when a hardware error occurs, kernel will
    be notified via NMI, MCE or some other method, then kernel will
    process the error condition, report it, and recover it if possible.
    But sometime, the situation is so bad, so that firmware may choose to
    reset directly without notifying Linux kernel.
    
    Linux kernel can use the Boot Error Record Table (BERT) to get the
    un-notified hardware errors that occurred in a previous boot. In this
    patch, the error information is reported via printk.
    
    For more information about BERT, please refer to ACPI Specification
    version 6.0, section 18.3.1:
      http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf
    
    The following log is a BERT record after system reboot because of hitting
    a fatal memory error:
    BERT: Error records from previous boot:
    [Hardware Error]: It has been corrected by h/w and requires no further action
    [Hardware Error]: event severity: corrected
    [Hardware Error]:  Error 0, type: recoverable
    [Hardware Error]:   section_type: memory error
    [Hardware Error]:   error_status: 0x0000000000000400
    [Hardware Error]:   physical_address: 0xffffffffffffffff
    [Hardware Error]:   card: 1 module: 2 bank: 3 row: 1 column: 2 bit_position: 5
    [Hardware Error]:   error_type: 2, single-bit ECC
    
    [Tomasz Nowicki: Clear error status at the end of error handling]
    [Tony: Applied some cleanups suggested by Fu Wei]
    [Fu Wei: delete EXPORT_SYMBOL_GPL(bert_disable), improve the code]
    Signed-off-by: default avatarHuang Ying <ying.huang@intel.com>
    Signed-off-by: default avatarTomasz Nowicki <tomasz.nowicki@linaro.org>
    Signed-off-by: default avatarChen, Gong <gong.chen@linux.intel.com>
    Tested-by: default avatarJonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
    Signed-off-by: default avatarFu Wei <fu.wei@linaro.org>
    Tested-by: default avatarTyler Baicar <tbaicar@codeaurora.org>
    Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
    Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    a3e2acc5
bert.c 3.67 KB