Re: [PATCH v3 2/5] x86/boot: Add max_addr field in struct boot_params

[Baoquan He]

On 08/30/19 at 05:47pm, Masayoshi Mizuma wrote:
> From: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
> 
> Add max_addr field in struct boot_params. max_addr shows the
> maximum memory address to be reachable by memory hot-add.
> max_addr is set by parsing ACPI SRAT.
> 
> Signed-off-by: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
> ---
>  Documentation/x86/zero-page.rst       | 4 ++++
>  arch/x86/include/uapi/asm/bootparam.h | 2 +-
>  2 files changed, 5 insertions(+), 1 deletion(-)

Reviewed-by: Baoquan He <bhe@xxxxxxxxxx>

Thanks
Baoquan

> 
> diff --git a/Documentation/x86/zero-page.rst b/Documentation/x86/zero-page.rst
> index f088f5881..cc3938d68 100644
> --- a/Documentation/x86/zero-page.rst
> +++ b/Documentation/x86/zero-page.rst
> @@ -19,6 +19,7 @@ Offset/Size	Proto	Name			Meaning
>  058/008		ALL	tboot_addr      	Physical address of tboot shared page
>  060/010		ALL	ist_info		Intel SpeedStep (IST) BIOS support information
>  						(struct ist_info)
> +078/010		ALL	max_addr		The possible maximum physical memory address [1]_
>  080/010		ALL	hd0_info		hd0 disk parameter, OBSOLETE!!
>  090/010		ALL	hd1_info		hd1 disk parameter, OBSOLETE!!
>  0A0/010		ALL	sys_desc_table		System description table (struct sys_desc_table),
> @@ -43,3 +44,6 @@ Offset/Size	Proto	Name			Meaning
>  						(array of struct e820_entry)
>  D00/1EC		ALL	eddbuf			EDD data (array of struct edd_info)
>  ===========	=====	=======================	=================================================
> +
> +.. [1] max_addr shows the maximum memory address to be reachable by memory
> +       hot-add. max_addr is set by parsing ACPI SRAT.
> diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
> index c895df548..6efad338b 100644
> --- a/arch/x86/include/uapi/asm/bootparam.h
> +++ b/arch/x86/include/uapi/asm/bootparam.h
> @@ -158,7 +158,7 @@ struct boot_params {
>  	__u64  tboot_addr;				/* 0x058 */
>  	struct ist_info ist_info;			/* 0x060 */
>  	__u64 acpi_rsdp_addr;				/* 0x070 */
> -	__u8  _pad3[8];					/* 0x078 */
> +	__u64 max_addr;					/* 0x078 */
>  	__u8  hd0_info[16];	/* obsolete! */		/* 0x080 */
>  	__u8  hd1_info[16];	/* obsolete! */		/* 0x090 */
>  	struct sys_desc_table sys_desc_table; /* obsolete! */	/* 0x0a0 */
> -- 
> 2.18.1
>