From c3e6088e1036f8084bc7444b38437da136b7588b Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Wed, 20 Jul 2011 16:09:29 +0800 Subject: [PATCH] ACPI, APEI, EINJ Param support is disabled by default EINJ parameter support is only usable for some specific BIOS. Originally, it is expected to have no harm for BIOS does not support it. But now, we found it will cause issue (memory overwriting) for some BIOS. So param support is disabled by default and only enabled when newly added module parameter named "param_extension" is explicitly specified. Signed-off-by: Huang Ying Cc: Matthew Garrett Acked-by: Don Zickus Acked-by: Tony Luck Signed-off-by: Len Brown --- Documentation/acpi/apei/einj.txt | 11 +++++++-- drivers/acpi/apei/einj.c | 39 ++++++++++++++++++++------------ 2 files changed, 33 insertions(+), 17 deletions(-) diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/acpi/apei/einj.txt index dfab71848dc8..5cc699ba5453 100644 --- a/Documentation/acpi/apei/einj.txt +++ b/Documentation/acpi/apei/einj.txt @@ -48,12 +48,19 @@ directory apei/einj. The following files are provided. - param1 This file is used to set the first error parameter value. Effect of parameter depends on error_type specified. For memory error, this is - physical memory address. + physical memory address. Only available if param_extension module + parameter is specified. - param2 This file is used to set the second error parameter value. Effect of parameter depends on error_type specified. For memory error, this is - physical memory address mask. + physical memory address mask. Only available if param_extension + module parameter is specified. + +Injecting parameter support is a BIOS version specific extension, that +is, it only works on some BIOS version. If you want to use it, please +make sure your BIOS version has the proper support and specify +"param_extension=y" in module parameter. For more information about EINJ, please refer to ACPI specification version 4.0, section 17.5. diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c index ab821f1cfa1f..589b96c38704 100644 --- a/drivers/acpi/apei/einj.c +++ b/drivers/acpi/apei/einj.c @@ -46,7 +46,8 @@ * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the * EINJ table through an unpublished extension. Use with caution as * most will ignore the parameter and make their own choice of address - * for error injection. + * for error injection. This extension is used only if + * param_extension module parameter is specified. */ struct einj_parameter { u64 type; @@ -65,6 +66,9 @@ struct einj_parameter { ((struct acpi_whea_header *)((char *)(tab) + \ sizeof(struct acpi_table_einj))) +static bool param_extension; +module_param(param_extension, bool, 0); + static struct acpi_table_einj *einj_tab; static struct apei_resources einj_resources; @@ -489,14 +493,6 @@ static int __init einj_init(void) einj_debug_dir, NULL, &error_type_fops); if (!fentry) goto err_cleanup; - fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR, - einj_debug_dir, &error_param1); - if (!fentry) - goto err_cleanup; - fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR, - einj_debug_dir, &error_param2); - if (!fentry) - goto err_cleanup; fentry = debugfs_create_file("error_inject", S_IWUSR, einj_debug_dir, NULL, &error_inject_fops); if (!fentry) @@ -513,12 +509,23 @@ static int __init einj_init(void) rc = apei_exec_pre_map_gars(&ctx); if (rc) goto err_release; - param_paddr = einj_get_parameter_address(); - if (param_paddr) { - einj_param = ioremap(param_paddr, sizeof(*einj_param)); - rc = -ENOMEM; - if (!einj_param) - goto err_unmap; + if (param_extension) { + param_paddr = einj_get_parameter_address(); + if (param_paddr) { + einj_param = ioremap(param_paddr, sizeof(*einj_param)); + rc = -ENOMEM; + if (!einj_param) + goto err_unmap; + fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR, + einj_debug_dir, &error_param1); + if (!fentry) + goto err_unmap; + fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR, + einj_debug_dir, &error_param2); + if (!fentry) + goto err_unmap; + } else + pr_warn(EINJ_PFX "Parameter extension is not supported.\n"); } pr_info(EINJ_PFX "Error INJection is initialized.\n"); @@ -526,6 +533,8 @@ static int __init einj_init(void) return 0; err_unmap: + if (einj_param) + iounmap(einj_param); apei_exec_post_unmap_gars(&ctx); err_release: apei_resources_release(&einj_resources);