Re: [PATCH v2 1/2] ACPI: Fix the issue that auto SSDT loading is conflict with customized SSDT that is included by the customized DSDT.

["Rafael J. Wysocki" <rafael.j.wysocki@intel.com>]

On 5/9/2014 10:44 AM, Lv Zheng wrote:
> This patch fixes the following issue:
> User can specify a DSDT with SSDT embedded, in which case, no_static_ssdt
> must be enforced.  If we don't do that, then:
> 1. The namespace object conflicts will result in an AE_ALREADY_EXISTS
>     exception;
> 2. The namespace objects that are deleted from the original SSDT will be
>     restored by the auto loading of the original SSDT.
>
> Note that the DSDT customization is a compile-time feature, thus the SSDT
> inclusion indication of the DSDT customization is also implemented as a
> compile-time configurable.
>
> Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=69711
> Original-by: Enrico Etxe Arte <goitizena.generoa@gmail.com>
> Signed-off-by: Lv Zheng <lv.zheng@intel.com>
> ---
>   drivers/acpi/Kconfig    |    8 ++++++++
>   drivers/acpi/internal.h |    5 +++++
>   drivers/acpi/osl.c      |   14 +++++++++++++-
>   drivers/acpi/tables.c   |    2 ++
>   4 files changed, 28 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index c0160bb..6fef394 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -233,6 +233,14 @@ config ACPI_CUSTOM_DSDT
>   	bool
>   	default ACPI_CUSTOM_DSDT_FILE != ""
>   
> +config ACPI_CUSTOM_DSDT_WITH_SSDT
> +	bool "Customize DSDT with SSDT tables included"
> +	depends on ACPI_CUSTOM_DSDT

If you think that we really have to have a separate CONFIG_ option here, 
I would prefer ACPI_CUSTOM_DSDT to become a menu with a choice to build 
it either with or without embedded SSDTs.

> +	help
> +	  This option turns on acpi.no_static_ssdt by default.

This description requires the user building the kernel to know what the 
above command line option means which isn't very useful.

> +
> +	  If the SSDT tables has been merged into the custom DSDT file, say Y.
> +
>   config ACPI_INITRD_TABLE_OVERRIDE
>   	bool "ACPI tables override via initrd"
>   	depends on BLK_DEV_INITRD && X86
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index 9573913..f84ef59 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -57,6 +57,11 @@ void acpi_cmos_rtc_init(void);
>   #else
>   static inline void acpi_cmos_rtc_init(void) {}
>   #endif
> +#ifdef CONFIG_ACPI_CUSTOM_DSDT_WITH_SSDT
> +void __init acpi_ssdt_customized(void);
> +#else
> +static inline void acpi_ssdt_customized(void) {}
> +#endif
>   
>   extern bool acpi_force_hot_remove;
>   
> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
> index 9aeae41..089e55d 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -1770,15 +1770,27 @@ acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
>   }
>   #endif
>   
> -static int __init acpi_no_static_ssdt_setup(char *s)
> +static void __init acpi_set_no_static_ssdt(void)
>   {
>   	acpi_gbl_disable_ssdt_table_install = TRUE;
>   	pr_info("ACPI: static SSDT installation disabled\n");
> +}
> +
> +#ifdef CONFIG_ACPI_CUSTOM_DSDT_WITH_SSDT
> +void __init acpi_ssdt_customized(void)
> +{
> +	acpi_set_no_static_ssdt();
> +}
> +#else
> +static int __init acpi_no_static_ssdt_setup(char *s)
> +{
> +	acpi_set_no_static_ssdt();
>   
>   	return 0;
>   }
>   
>   early_param("acpi_no_static_ssdt", acpi_no_static_ssdt_setup);
> +#endif
>   
>   static int __init acpi_disable_return_repair(char *s)
>   {
> diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
> index 2178229..aaf2177 100644
> --- a/drivers/acpi/tables.c
> +++ b/drivers/acpi/tables.c
> @@ -184,6 +184,7 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
>   	}
>   }
>   
> +#include "internal.h"
>   
>   int __init
>   acpi_table_parse_entries(char *id,
> @@ -333,6 +334,7 @@ int __init acpi_table_init(void)
>   {
>   	acpi_status status;
>   
> +	acpi_ssdt_customized();
>   	status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
>   	if (ACPI_FAILURE(status))
>   		return -EINVAL;