Commit-ID: 09c205afde70c15f20ca76ba0a57409dad175fd0 Gitweb: http://git.kernel.org/tip/09c205afde70c15f20ca76ba0a57409dad175fd0 Author: H. Peter Anvin <h...@linux.intel.com> AuthorDate: Sun, 27 Jan 2013 10:43:28 -0800 Committer: H. Peter Anvin <h...@linux.intel.com> CommitDate: Sun, 27 Jan 2013 15:56:37 -0800
x86, boot: Define the 2.12 bzImage boot protocol Define the 2.12 bzImage boot protocol: add xloadflags and additional fields to allow the command line, initramfs and struct boot_params to live above the 4 GiB mark. The xloadflags now communicates if this is a 64-bit kernel with the legacy 64-bit entry point and which of the EFI handover entry points are supported. Avoid adding new read flags to loadflags because of claimed bootloaders testing the whole byte for == 1 to determine bzImageness at least until the issue can be researched further. This is based on patches by Yinghai Lu and David Woodhouse. Originally-by: Yinghai Lu <ying...@kernel.org> Originally-by: David Woodhouse <dw...@infradead.org> Acked-by: Yinghai Lu <ying...@kernel.org> Acked-by: David Woodhouse <dw...@infradead.org> Acked-by: Matt Fleming <matt.flem...@intel.com> Signed-off-by: H. Peter Anvin <h...@linux.intel.com> Link: http://lkml.kernel.org/r/1359058816-7615-26-git-send-email-ying...@kernel.org Cc: Rob Landley <r...@landley.net> Cc: Gokul Caushik <caush...@gmail.com> Cc: Josh Triplett <j...@joshtriplett.org> Cc: Joe Millenbach <jmillenb...@gmail.com> --- Documentation/x86/boot.txt | 27 ++++++++++++++- Documentation/x86/zero-page.txt | 4 +++ arch/x86/boot/header.S | 39 ++++++++++++++++------ arch/x86/boot/setup.ld | 2 +- arch/x86/include/uapi/asm/bootparam.h | 63 +++++++++++++++++++++++++---------- 5 files changed, 106 insertions(+), 29 deletions(-) diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 406d82d..3edb4c2 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -57,6 +57,10 @@ Protocol 2.10: (Kernel 2.6.31) Added a protocol for relaxed alignment Protocol 2.11: (Kernel 3.6) Added a field for offset of EFI handover protocol entry point. +Protocol 2.12: (Kernel 3.9) Added the xloadflags field and extension fields + to struct boot_params for for loading bzImage and ramdisk + above 4G in 64bit. + **** MEMORY LAYOUT The traditional memory map for the kernel loader, used for Image or @@ -182,7 +186,7 @@ Offset Proto Name Meaning 0230/4 2.05+ kernel_alignment Physical addr alignment required for kernel 0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not 0235/1 2.10+ min_alignment Minimum alignment, as a power of two -0236/2 N/A pad3 Unused +0236/2 2.12+ xloadflags Boot protocol option flags 0238/4 2.06+ cmdline_size Maximum size of the kernel command line 023C/4 2.07+ hardware_subarch Hardware subarchitecture 0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data @@ -582,6 +586,27 @@ Protocol: 2.10+ misaligned kernel. Therefore, a loader should typically try each power-of-two alignment from kernel_alignment down to this alignment. +Field name: xloadflags +Type: read +Offset/size: 0x236/2 +Protocol: 2.12+ + + This field is a bitmask. + + Bit 0 (read): XLF_KERNEL_64 + - If 1, this kernel has the legacy 64-bit entry point at 0x200. + + Bit 1 (read): XLF_CAN_BE_LOADED_ABOVE_4G + - If 1, kernel/boot_params/cmdline/ramdisk can be above 4G. + + Bit 2 (read): XLF_EFI_HANDOVER_32 + - If 1, the kernel supports the 32-bit EFI handoff entry point + given at handover_offset. + + Bit 3 (read): XLF_EFI_HANDOVER_64 + - If 1, the kernel supports the 64-bit EFI handoff entry point + given at handover_offset + 0x200. + Field name: cmdline_size Type: read Offset/size: 0x238/4 diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt index cf5437d..199f453 100644 --- a/Documentation/x86/zero-page.txt +++ b/Documentation/x86/zero-page.txt @@ -19,6 +19,9 @@ Offset Proto Name Meaning 090/010 ALL hd1_info hd1 disk parameter, OBSOLETE!! 0A0/010 ALL sys_desc_table System description table (struct sys_desc_table) 0B0/010 ALL olpc_ofw_header OLPC's OpenFirmware CIF and friends +0C0/004 ALL ext_ramdisk_image ramdisk_image high 32bits +0C4/004 ALL ext_ramdisk_size ramdisk_size high 32bits +0C8/004 ALL ext_cmd_line_ptr cmd_line_ptr high 32bits 140/080 ALL edid_info Video mode setup (struct edid_info) 1C0/020 ALL efi_info EFI 32 information (struct efi_info) 1E0/004 ALL alk_mem_k Alternative mem check, in KB @@ -27,6 +30,7 @@ Offset Proto Name Meaning 1E9/001 ALL eddbuf_entries Number of entries in eddbuf (below) 1EA/001 ALL edd_mbr_sig_buf_entries Number of entries in edd_mbr_sig_buffer (below) +1EF/001 ALL sentinel Used to detect broken bootloaders 290/040 ALL edd_mbr_sig_buffer EDD MBR signatures 2D0/A00 ALL e820_map E820 memory map table (array of struct e820entry) diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 8c132a6..944ce59 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -21,6 +21,7 @@ #include <asm/e820.h> #include <asm/page_types.h> #include <asm/setup.h> +#include <asm/bootparam.h> #include "boot.h" #include "voffset.h" #include "zoffset.h" @@ -255,6 +256,9 @@ section_table: # header, from the old boot sector. .section ".header", "a" + .globl sentinel +sentinel: .byte 0xff, 0xff /* Used to detect broken loaders */ + .globl hdr hdr: setup_sects: .byte 0 /* Filled in by build.c */ @@ -279,7 +283,7 @@ _start: # Part 2 of the header, from the old setup.S .ascii "HdrS" # header signature - .word 0x020b # header version number (>= 0x0105) + .word 0x020c # header version number (>= 0x0105) # or else old loadlin-1.5 will fail) .globl realmode_swtch realmode_swtch: .word 0, 0 # default_switch, SETUPSEG @@ -297,13 +301,7 @@ type_of_loader: .byte 0 # 0 means ancient bootloader, newer # flags, unused bits must be zero (RFU) bit within loadflags loadflags: -LOADED_HIGH = 1 # If set, the kernel is loaded high -CAN_USE_HEAP = 0x80 # If set, the loader also has set - # heap_end_ptr to tell how much - # space behind setup.S can be used for - # heap purposes. - # Only the loader knows what is free - .byte LOADED_HIGH + .byte LOADED_HIGH # The kernel is to be loaded high setup_move_size: .word 0x8000 # size to move, when setup is not # loaded at 0x90000. We will move setup @@ -369,7 +367,23 @@ relocatable_kernel: .byte 1 relocatable_kernel: .byte 0 #endif min_alignment: .byte MIN_KERNEL_ALIGN_LG2 # minimum alignment -pad3: .word 0 + +xloadflags: +#ifdef CONFIG_X86_64 +# define XLF0 XLF_KERNEL_64 /* 64-bit kernel */ +#else +# define XLF0 0 +#endif +#ifdef CONFIG_EFI_STUB +# ifdef CONFIG_X86_64 +# define XLF23 XLF_EFI_HANDOVER_64 /* 64-bit EFI handover ok */ +# else +# define XLF23 XLF_EFI_HANDOVER_32 /* 32-bit EFI handover ok */ +# endif +#else +# define XLF23 0 +#endif + .word XLF0 | XLF23 cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line, #added with boot protocol @@ -397,8 +411,13 @@ pref_address: .quad LOAD_PHYSICAL_ADDR # preferred load addr #define INIT_SIZE VO_INIT_SIZE #endif init_size: .long INIT_SIZE # kernel initialization size -handover_offset: .long 0x30 # offset to the handover +handover_offset: +#ifdef CONFIG_EFI_STUB + .long 0x30 # offset to the handover # protocol entry point +#else + .long 0 +#endif # End of setup header ##################################################### diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld index 03c0683..96a6c75 100644 --- a/arch/x86/boot/setup.ld +++ b/arch/x86/boot/setup.ld @@ -13,7 +13,7 @@ SECTIONS .bstext : { *(.bstext) } .bsdata : { *(.bsdata) } - . = 497; + . = 495; .header : { *(.header) } .entrytext : { *(.entrytext) } .inittext : { *(.inittext) } diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index 92862cd..c15ddaf 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -1,6 +1,31 @@ #ifndef _ASM_X86_BOOTPARAM_H #define _ASM_X86_BOOTPARAM_H +/* setup_data types */ +#define SETUP_NONE 0 +#define SETUP_E820_EXT 1 +#define SETUP_DTB 2 +#define SETUP_PCI 3 + +/* ram_size flags */ +#define RAMDISK_IMAGE_START_MASK 0x07FF +#define RAMDISK_PROMPT_FLAG 0x8000 +#define RAMDISK_LOAD_FLAG 0x4000 + +/* loadflags */ +#define LOADED_HIGH (1<<0) +#define QUIET_FLAG (1<<5) +#define KEEP_SEGMENTS (1<<6) +#define CAN_USE_HEAP (1<<7) + +/* xloadflags */ +#define XLF_KERNEL_64 (1<<0) +#define XLF_CAN_BE_LOADED_ABOVE_4G (1<<1) +#define XLF_EFI_HANDOVER_32 (1<<2) +#define XLF_EFI_HANDOVER_64 (1<<3) + +#ifndef __ASSEMBLY__ + #include <linux/types.h> #include <linux/screen_info.h> #include <linux/apm_bios.h> @@ -9,12 +34,6 @@ #include <asm/ist.h> #include <video/edid.h> -/* setup data types */ -#define SETUP_NONE 0 -#define SETUP_E820_EXT 1 -#define SETUP_DTB 2 -#define SETUP_PCI 3 - /* extensible setup data list node */ struct setup_data { __u64 next; @@ -28,9 +47,6 @@ struct setup_header { __u16 root_flags; __u32 syssize; __u16 ram_size; -#define RAMDISK_IMAGE_START_MASK 0x07FF -#define RAMDISK_PROMPT_FLAG 0x8000 -#define RAMDISK_LOAD_FLAG 0x4000 __u16 vid_mode; __u16 root_dev; __u16 boot_flag; @@ -42,10 +58,6 @@ struct setup_header { __u16 kernel_version; __u8 type_of_loader; __u8 loadflags; -#define LOADED_HIGH (1<<0) -#define QUIET_FLAG (1<<5) -#define KEEP_SEGMENTS (1<<6) -#define CAN_USE_HEAP (1<<7) __u16 setup_move_size; __u32 code32_start; __u32 ramdisk_image; @@ -58,7 +70,8 @@ struct setup_header { __u32 initrd_addr_max; __u32 kernel_alignment; __u8 relocatable_kernel; - __u8 _pad2[3]; + __u8 min_alignment; + __u16 xloadflags; __u32 cmdline_size; __u32 hardware_subarch; __u64 hardware_subarch_data; @@ -106,7 +119,10 @@ struct boot_params { __u8 hd1_info[16]; /* obsolete! */ /* 0x090 */ struct sys_desc_table sys_desc_table; /* 0x0a0 */ struct olpc_ofw_header olpc_ofw_header; /* 0x0b0 */ - __u8 _pad4[128]; /* 0x0c0 */ + __u32 ext_ramdisk_image; /* 0x0c0 */ + __u32 ext_ramdisk_size; /* 0x0c4 */ + __u32 ext_cmd_line_ptr; /* 0x0c8 */ + __u8 _pad4[116]; /* 0x0cc */ struct edid_info edid_info; /* 0x140 */ struct efi_info efi_info; /* 0x1c0 */ __u32 alt_mem_k; /* 0x1e0 */ @@ -115,7 +131,20 @@ struct boot_params { __u8 eddbuf_entries; /* 0x1e9 */ __u8 edd_mbr_sig_buf_entries; /* 0x1ea */ __u8 kbd_status; /* 0x1eb */ - __u8 _pad6[5]; /* 0x1ec */ + __u8 _pad5[3]; /* 0x1ec */ + /* + * The sentinel is set to a nonzero value (0xff) in header.S. + * + * A bootloader is supposed to only take setup_header and put + * it into a clean boot_params buffer. If it turns out that + * it is clumsy or too generous with the buffer, it most + * probably will pick up the sentinel variable too. The fact + * that this variable then is still 0xff will let kernel + * know that some variables in boot_params are invalid and + * kernel should zero out certain portions of boot_params. + */ + __u8 sentinel; /* 0x1ef */ + __u8 _pad6[1]; /* 0x1f0 */ struct setup_header hdr; /* setup header */ /* 0x1f1 */ __u8 _pad7[0x290-0x1f1-sizeof(struct setup_header)]; __u32 edd_mbr_sig_buffer[EDD_MBR_SIG_MAX]; /* 0x290 */ @@ -134,6 +163,6 @@ enum { X86_NR_SUBARCHS, }; - +#endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_BOOTPARAM_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
