Commit c3e6088e authored by Huang Ying's avatar Huang Ying Committed by Len Brown
Browse files

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: default avatarHuang Ying <ying.huang@intel.com>
Cc: Matthew Garrett <mjg@redhat.com>
Acked-by: default avatarDon Zickus <dzickus@redhat.com>
Acked-by: default avatarTony Luck <tony.luck@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 70cb6e1d

Documentation/acpi/apei/einj.txt

+9 −2
Original line number Diff line number Diff line
@@ -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.

drivers/acpi/apei/einj.c

+24 −15
Original line number Diff line number Diff line
@@ -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 * EINJ table through an unpublished extension.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;

	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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE