path: root/Documentation/kernel-parameters.txt
diff options
authorHuang Ying <ying.huang@intel.com>2016-06-29 13:04:29 -0700
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2016-06-29 23:35:05 +0200
commita3e2acc5e37b22b6808a0b8e46887c3577de9c9e (patch)
treee5d8f83cee1504d31d034df5f63283b0f98094ca /Documentation/kernel-parameters.txt
parentdba648300e890fb6961d896ab3bd60704815adf3 (diff)
ACPI / APEI: Add Boot Error Record Table (BERT) support
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: Huang Ying <ying.huang@intel.com> Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org> Signed-off-by: Chen, Gong <gong.chen@linux.intel.com> Tested-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org> Signed-off-by: Fu Wei <fu.wei@linaro.org> Tested-by: Tyler Baicar <tbaicar@codeaurora.org> Reviewed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/kernel-parameters.txt')
1 files changed, 3 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 82b42c958d1c..f565259167d7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -582,6 +582,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
bootmem_debug [KNL] Enable bootmem allocator debug messages.
+ bert_disable [ACPI]
+ Disable BERT OS support on buggy BIOSes.
bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
bttv.radio= Most important insmod options are available as
kernel args too.