linux_dsm_epyc7002/arch/x86/include/uapi/asm/bootparam.h
Baoquan He f2d08c5d3b x86/boot: Add xloadflags bits to check for 5-level paging support
The current kernel supports 5-level paging mode, and supports dynamically
choosing the paging mode during bootup depending on the kernel image,
hardware and kernel parameter settings. This flexibility brings several
issues to kexec/kdump:

1) Dynamic switching between paging modes requires support in the target
   kernel. This means kexec from a 5-level paging kernel into a kernel
   which does not support mode switching is not possible. So the loader
   needs to be able to analyze the supported paging modes of the kexec
   target kernel.

2) If running on a 5-level paging kernel and the kexec target kernel is a
   4-level paging kernel, the target immage cannot be loaded above the 64TB
   address space limit. But the kexec loader searches for a load area from
   top to bottom which would eventually put the target kernel above 64TB
   when the machine has large enough RAM size. So the loader needs to be
   able to analyze the paging mode of the target kernel to load it at a
   suitable spot in the address space.

Solution:

Add two bits XLF_5LEVEL and XLF_5LEVEL_ENABLED:

 - Bit XLF_5LEVEL indicates whether 5-level paging mode switching support
   is available. (Issue #1)

 - Bit XLF_5LEVEL_ENABLED indicates whether the kernel was compiled with
   full 5-level paging support (CONFIG_X86_5LEVEL=y). (Issue #2)

The loader will use these bits to verify whether the target kernel is
suitable to be kexec'ed to from a 5-level paging kernel and to determine
the constraints of the target kernel load address.

The flags will be used by the kernel kexec subsystem and the userspace
kexec tools.

[ tglx: Massaged changelog ]

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: dyoung@redhat.com
Link: https://lkml.kernel.org/r/20190524073810.24298-2-bhe@redhat.com
2019-06-28 07:14:59 +02:00

253 lines
7.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#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
#define SETUP_EFI 4
#define SETUP_APPLE_PROPERTIES 5
#define SETUP_JAILHOUSE 6
/* 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 KASLR_FLAG (1<<1)
#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)
#define XLF_EFI_KEXEC (1<<4)
#define XLF_5LEVEL (1<<5)
#define XLF_5LEVEL_ENABLED (1<<6)
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/screen_info.h>
#include <linux/apm_bios.h>
#include <linux/edd.h>
#include <asm/ist.h>
#include <video/edid.h>
/* extensible setup data list node */
struct setup_data {
__u64 next;
__u32 type;
__u32 len;
__u8 data[0];
};
struct setup_header {
__u8 setup_sects;
__u16 root_flags;
__u32 syssize;
__u16 ram_size;
__u16 vid_mode;
__u16 root_dev;
__u16 boot_flag;
__u16 jump;
__u32 header;
__u16 version;
__u32 realmode_swtch;
__u16 start_sys_seg;
__u16 kernel_version;
__u8 type_of_loader;
__u8 loadflags;
__u16 setup_move_size;
__u32 code32_start;
__u32 ramdisk_image;
__u32 ramdisk_size;
__u32 bootsect_kludge;
__u16 heap_end_ptr;
__u8 ext_loader_ver;
__u8 ext_loader_type;
__u32 cmd_line_ptr;
__u32 initrd_addr_max;
__u32 kernel_alignment;
__u8 relocatable_kernel;
__u8 min_alignment;
__u16 xloadflags;
__u32 cmdline_size;
__u32 hardware_subarch;
__u64 hardware_subarch_data;
__u32 payload_offset;
__u32 payload_length;
__u64 setup_data;
__u64 pref_address;
__u32 init_size;
__u32 handover_offset;
} __attribute__((packed));
struct sys_desc_table {
__u16 length;
__u8 table[14];
};
/* Gleaned from OFW's set-parameters in cpu/x86/pc/linux.fth */
struct olpc_ofw_header {
__u32 ofw_magic; /* OFW signature */
__u32 ofw_version;
__u32 cif_handler; /* callback into OFW */
__u32 irq_desc_table;
} __attribute__((packed));
struct efi_info {
__u32 efi_loader_signature;
__u32 efi_systab;
__u32 efi_memdesc_size;
__u32 efi_memdesc_version;
__u32 efi_memmap;
__u32 efi_memmap_size;
__u32 efi_systab_hi;
__u32 efi_memmap_hi;
};
/*
* This is the maximum number of entries in struct boot_params::e820_table
* (the zeropage), which is part of the x86 boot protocol ABI:
*/
#define E820_MAX_ENTRIES_ZEROPAGE 128
/*
* The E820 memory region entry of the boot protocol ABI:
*/
struct boot_e820_entry {
__u64 addr;
__u64 size;
__u32 type;
} __attribute__((packed));
/*
* Smallest compatible version of jailhouse_setup_data required by this kernel.
*/
#define JAILHOUSE_SETUP_REQUIRED_VERSION 1
/*
* The boot loader is passing platform information via this Jailhouse-specific
* setup data structure.
*/
struct jailhouse_setup_data {
__u16 version;
__u16 compatible_version;
__u16 pm_timer_address;
__u16 num_cpus;
__u64 pci_mmconfig_base;
__u32 tsc_khz;
__u32 apic_khz;
__u8 standard_ioapic;
__u8 cpu_ids[255];
} __attribute__((packed));
/* The so-called "zeropage" */
struct boot_params {
struct screen_info screen_info; /* 0x000 */
struct apm_bios_info apm_bios_info; /* 0x040 */
__u8 _pad2[4]; /* 0x054 */
__u64 tboot_addr; /* 0x058 */
struct ist_info ist_info; /* 0x060 */
__u64 acpi_rsdp_addr; /* 0x070 */
__u8 _pad3[8]; /* 0x078 */
__u8 hd0_info[16]; /* obsolete! */ /* 0x080 */
__u8 hd1_info[16]; /* obsolete! */ /* 0x090 */
struct sys_desc_table sys_desc_table; /* obsolete! */ /* 0x0a0 */
struct olpc_ofw_header olpc_ofw_header; /* 0x0b0 */
__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 */
__u32 scratch; /* Scratch field! */ /* 0x1e4 */
__u8 e820_entries; /* 0x1e8 */
__u8 eddbuf_entries; /* 0x1e9 */
__u8 edd_mbr_sig_buf_entries; /* 0x1ea */
__u8 kbd_status; /* 0x1eb */
__u8 secure_boot; /* 0x1ec */
__u8 _pad5[2]; /* 0x1ed */
/*
* 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 */
struct boot_e820_entry e820_table[E820_MAX_ENTRIES_ZEROPAGE]; /* 0x2d0 */
__u8 _pad8[48]; /* 0xcd0 */
struct edd_info eddbuf[EDDMAXNR]; /* 0xd00 */
__u8 _pad9[276]; /* 0xeec */
} __attribute__((packed));
/**
* enum x86_hardware_subarch - x86 hardware subarchitecture
*
* The x86 hardware_subarch and hardware_subarch_data were added as of the x86
* boot protocol 2.07 to help distinguish and support custom x86 boot
* sequences. This enum represents accepted values for the x86
* hardware_subarch. Custom x86 boot sequences (not X86_SUBARCH_PC) do not
* have or simply *cannot* make use of natural stubs like BIOS or EFI, the
* hardware_subarch can be used on the Linux entry path to revector to a
* subarchitecture stub when needed. This subarchitecture stub can be used to
* set up Linux boot parameters or for special care to account for nonstandard
* handling of page tables.
*
* These enums should only ever be used by x86 code, and the code that uses
* it should be well contained and compartamentalized.
*
* KVM and Xen HVM do not have a subarch as these are expected to follow
* standard x86 boot entries. If there is a genuine need for "hypervisor" type
* that should be considered separately in the future. Future guest types
* should seriously consider working with standard x86 boot stubs such as
* the BIOS or EFI boot stubs.
*
* WARNING: this enum is only used for legacy hacks, for platform features that
* are not easily enumerated or discoverable. You should not ever use
* this for new features.
*
* @X86_SUBARCH_PC: Should be used if the hardware is enumerable using standard
* PC mechanisms (PCI, ACPI) and doesn't need a special boot flow.
* @X86_SUBARCH_LGUEST: Used for x86 hypervisor demo, lguest, deprecated
* @X86_SUBARCH_XEN: Used for Xen guest types which follow the PV boot path,
* which start at asm startup_xen() entry point and later jump to the C
* xen_start_kernel() entry point. Both domU and dom0 type of guests are
* currently supportd through this PV boot path.
* @X86_SUBARCH_INTEL_MID: Used for Intel MID (Mobile Internet Device) platform
* systems which do not have the PCI legacy interfaces.
* @X86_SUBARCH_CE4100: Used for Intel CE media processor (CE4100) SoC for
* for settop boxes and media devices, the use of a subarch for CE4100
* is more of a hack...
*/
enum x86_hardware_subarch {
X86_SUBARCH_PC = 0,
X86_SUBARCH_LGUEST,
X86_SUBARCH_XEN,
X86_SUBARCH_INTEL_MID,
X86_SUBARCH_CE4100,
X86_NR_SUBARCHS,
};
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_BOOTPARAM_H */