Hi Borislav, On 7 January 2016 at 19:27, <fu.wei@xxxxxxxxxx> wrote: > From: Huang Ying <ying.huang@xxxxxxxxx> > > 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 error. > > BERT: Obtained BERT iomem region <00000000fe801000-00000000fe802000> for BERT. > [Hardware Error]: Error record from previous boot: > [Hardware Error]: event severity: fatal > [Hardware Error]: Error 0, type: fatal > [Hardware Error]: section_type: memory error > [Hardware Error]: physical_address: 0x00000000fe800000 > [Hardware Error]: physical_address_mask: 0x0000000000000fff > [Hardware Error]: card: 0 module: 1 bank: 0 device: 1 row: 1 column: 1 bit_pos > > [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@xxxxxxxxx> > Signed-off-by: Tomasz Nowicki <tomasz.nowicki@xxxxxxxxxx> > Signed-off-by: Chen, Gong <gong.chen@xxxxxxxxxxxxxxx> > Tested-by: Jonathan (Zhixiong) Zhang <zjzhang@xxxxxxxxxxxxxx> > Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx> > Signed-off-by: Fu Wei <fu.wei@xxxxxxxxxx> > Tested-by: Tyler Baicar <tbaicar@xxxxxxxxxxxxxx> > --- > Changelog: > v3: Merge the two patches > Do some improvements according to Borislav's suggestion. > > v2: https://lkml.org/lkml/2015/8/18/336 > Delete EXPORT_SYMBOL_GPL(bert_disable), because "bert_disable" is only used > in bert.c for now. > Do some code-style cleanups. > > v1: The first upstream version submitted in linux-acpi mailing list: > http://www.spinics.net/lists/linux-acpi/msg57384.html > > Documentation/kernel-parameters.txt | 3 + > drivers/acpi/apei/Makefile | 2 +- > drivers/acpi/apei/bert.c | 158 ++++++++++++++++++++++++++++++++++++ > include/acpi/apei.h | 1 + > 4 files changed, 163 insertions(+), 1 deletion(-) > create mode 100644 drivers/acpi/apei/bert.c > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 742f69d..2310e97 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -555,6 +555,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > > bootmem_debug [KNL] Enable bootmem allocator debug messages. > > + bert_disable [ACPI] > + Disable Boot Error Record Table (BERT) support. > + This comes from the original version of BERT patch But I don't think we need this, and I don't see any benefit of this. Any suggestion ? Or anything I missed? > bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards) > bttv.radio= Most important insmod options are available as > kernel args too. > diff --git a/drivers/acpi/apei/Makefile b/drivers/acpi/apei/Makefile > index 5d575a9..e50573d 100644 > --- a/drivers/acpi/apei/Makefile > +++ b/drivers/acpi/apei/Makefile > @@ -3,4 +3,4 @@ obj-$(CONFIG_ACPI_APEI_GHES) += ghes.o > obj-$(CONFIG_ACPI_APEI_EINJ) += einj.o > obj-$(CONFIG_ACPI_APEI_ERST_DEBUG) += erst-dbg.o > > -apei-y := apei-base.o hest.o erst.o > +apei-y := apei-base.o hest.o erst.o bert.o > diff --git a/drivers/acpi/apei/bert.c b/drivers/acpi/apei/bert.c > new file mode 100644 > index 0000000..6f6ae38 > --- /dev/null > +++ b/drivers/acpi/apei/bert.c > @@ -0,0 +1,158 @@ > +/* > + * APEI Boot Error Record Table (BERT) support > + * > + * Copyright 2011 Intel Corp. > + * Author: Huang Ying <ying.huang@xxxxxxxxx> > + * > + * 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. > + * > + * For more information about BERT, please refer to ACPI Specification > + * version 4.0, section 17.3.1 > + * > + * This file is licensed under GPLv2. > + * > + */ > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/init.h> > +#include <linux/acpi.h> > +#include <linux/io.h> > + > +#include "apei-internal.h" > + > +#undef pr_fmt(fmt) > +#define pr_fmt(fmt) "BERT: " fmt > + > +static int bert_disable; > + > +static void __init bert_print_all(struct acpi_bert_region *region, > + unsigned int region_len) > +{ > + /* > + * We use cper_estatus_* which uses struct acpi_hest_generic_status, > + * struct acpi_hest_generic_status and acpi_bert_region are the same > + * (Generic Error Status Block), so we declare the "estatus" here. > + */ > + struct acpi_hest_generic_status *estatus = > + (struct acpi_hest_generic_status *)region; > + int remain = region_len; > + u32 estatus_len; > + > + /* The records have been polled*/ > + if (!estatus->block_status) > + return; > + > + while (remain > sizeof(struct acpi_bert_region)) { > + /* > + * Test Generic Error Status Block first, > + * if the data(Offset, Length) is invalid, we just return, > + * because we can't trust the length data from this block. > + */ > + if (cper_estatus_check(estatus)) { > + pr_err(FW_BUG "Invalid error record\n"); > + return; > + } > + > + estatus_len = cper_estatus_len(estatus); > + if (remain < estatus_len) { > + pr_err(FW_BUG "Invalid status block length (%u)\n", > + estatus_len); > + return; > + } > + > + pr_info_once(HW_ERR "Error records from previous boot:\n"); > + > + cper_estatus_print(KERN_INFO HW_ERR, estatus); > + > + /* > + * Because the boot error source is "one-time polled" type, > + * clear Block Status of current Generic Error Status Block, > + * once it's printed. > + */ > + estatus->block_status = 0; > + > + estatus = (void *)estatus + estatus_len; > + if (!estatus->block_status) > + return; /* No more error records */ > + > + remain -= estatus_len; > + } > +} > + > +static int __init setup_bert_disable(char *str) > +{ > + bert_disable = 1; > + > + return 0; > +} > +__setup("bert_disable", setup_bert_disable); > + > +static int __init bert_check_table(struct acpi_table_bert *bert_tab) > +{ > + if (bert_tab->header.length < sizeof(struct acpi_table_bert) || > + bert_tab->region_length < sizeof(struct acpi_bert_region)) > + return -EINVAL; > + > + return 0; > +} > + > +static int __init bert_init(void) > +{ > + struct acpi_bert_region *boot_error_region; > + struct acpi_table_bert *bert_tab; > + unsigned int region_len; > + acpi_status status; > + int rc = 0; > + > + if (acpi_disabled) > + return 0; > + > + if (bert_disable) { > + pr_info("Boot Error Record Table support is disabled\n"); > + return 0; > + } > + > + status = acpi_get_table(ACPI_SIG_BERT, 0, (struct acpi_table_header **)&bert_tab); > + if (status == AE_NOT_FOUND) > + return 0; > + if (ACPI_FAILURE(status)) { > + pr_err("get table failed, %s\n", acpi_format_exception(status)); > + return -EINVAL; > + } > + > + rc = bert_check_table(bert_tab); > + if (rc) { > + pr_err(FW_BUG "table invalid\n"); > + return rc; > + } > + > + region_len = bert_tab->region_length; > + if (!request_mem_region(bert_tab->address, region_len, "APEI BERT")) { > + pr_err("Can't request iomem region <%016llx-%016llx>\n", > + (unsigned long long)bert_tab->address, > + (unsigned long long)bert_tab->address + region_len - 1); > + return -EIO; > + } > + > + boot_error_region = ioremap_cache(bert_tab->address, region_len); > + if (boot_error_region) { > + bert_print_all(boot_error_region, region_len); > + iounmap(boot_error_region); > + } else { > + rc = -ENOMEM; > + } > + > + release_mem_region(bert_tab->address, region_len); > + > + return rc; > +} > + > +late_initcall(bert_init); > diff --git a/include/acpi/apei.h b/include/acpi/apei.h > index 76284bb..284801a 100644 > --- a/include/acpi/apei.h > +++ b/include/acpi/apei.h > @@ -23,6 +23,7 @@ extern bool ghes_disable; > #else > #define ghes_disable 1 > #endif > +extern int bert_disable; > > #ifdef CONFIG_ACPI_APEI > void __init acpi_hest_init(void); > -- > 2.5.0 > -- Best regards, Fu Wei Software Engineer Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch Ph: +86 21 61221326(direct) Ph: +86 186 2020 4684 (mobile) Room 1512, Regus One Corporate Avenue,Level 15, One Corporate Avenue,222 Hubin Road,Huangpu District, Shanghai,China 200021 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
