mirror of
https://github.com/torvalds/linux.git
synced 2025-10-30 08:08:27 +02:00
f367474b58
Currently, the kexec_file_load syscall on x86 does not support passing a device tree blob to the new kernel. Some embedded x86 systems use device trees. On these systems, failing to pass a device tree to the new kernel causes a boot failure. To add support for this, we copy the behavior of ARM64 and PowerPC and copy the current boot's device tree blob for use in the new kernel. We do this on x86 by passing the device tree blob as a setup_data entry in accordance with the x86 boot protocol. This behavior is gated behind the KEXEC_FILE_FORCE_DTB flag. Link: https://lkml.kernel.org/r/20250805211527.122367-3-makb@juniper.net Signed-off-by: Brian Mak <makb@juniper.net> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Dave Young <dyoung@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
73 lines
2.4 KiB
C
73 lines
2.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
|
|
#ifndef _UAPILINUX_KEXEC_H
|
|
#define _UAPILINUX_KEXEC_H
|
|
|
|
/* kexec system call - It loads the new kernel to boot into.
|
|
* kexec does not sync, or unmount filesystems so if you need
|
|
* that to happen you need to do that yourself.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
|
|
/* kexec flags for different usage scenarios */
|
|
#define KEXEC_ON_CRASH 0x00000001
|
|
#define KEXEC_PRESERVE_CONTEXT 0x00000002
|
|
#define KEXEC_UPDATE_ELFCOREHDR 0x00000004
|
|
#define KEXEC_CRASH_HOTPLUG_SUPPORT 0x00000008
|
|
#define KEXEC_ARCH_MASK 0xffff0000
|
|
|
|
/*
|
|
* Kexec file load interface flags.
|
|
* KEXEC_FILE_UNLOAD : Unload already loaded kexec/kdump image.
|
|
* KEXEC_FILE_ON_CRASH : Load/unload operation belongs to kdump image.
|
|
* KEXEC_FILE_NO_INITRAMFS : No initramfs is being loaded. Ignore the initrd
|
|
* fd field.
|
|
* KEXEC_FILE_FORCE_DTB : Force carrying over the current boot's DTB to the new
|
|
* kernel on x86. This is already the default behavior on
|
|
* some other architectures, like ARM64 and PowerPC.
|
|
*/
|
|
#define KEXEC_FILE_UNLOAD 0x00000001
|
|
#define KEXEC_FILE_ON_CRASH 0x00000002
|
|
#define KEXEC_FILE_NO_INITRAMFS 0x00000004
|
|
#define KEXEC_FILE_DEBUG 0x00000008
|
|
#define KEXEC_FILE_NO_CMA 0x00000010
|
|
#define KEXEC_FILE_FORCE_DTB 0x00000020
|
|
|
|
/* These values match the ELF architecture values.
|
|
* Unless there is a good reason that should continue to be the case.
|
|
*/
|
|
#define KEXEC_ARCH_DEFAULT ( 0 << 16)
|
|
#define KEXEC_ARCH_386 ( 3 << 16)
|
|
#define KEXEC_ARCH_68K ( 4 << 16)
|
|
#define KEXEC_ARCH_PARISC (15 << 16)
|
|
#define KEXEC_ARCH_X86_64 (62 << 16)
|
|
#define KEXEC_ARCH_PPC (20 << 16)
|
|
#define KEXEC_ARCH_PPC64 (21 << 16)
|
|
#define KEXEC_ARCH_IA_64 (50 << 16)
|
|
#define KEXEC_ARCH_ARM (40 << 16)
|
|
#define KEXEC_ARCH_S390 (22 << 16)
|
|
#define KEXEC_ARCH_SH (42 << 16)
|
|
#define KEXEC_ARCH_MIPS_LE (10 << 16)
|
|
#define KEXEC_ARCH_MIPS ( 8 << 16)
|
|
#define KEXEC_ARCH_AARCH64 (183 << 16)
|
|
#define KEXEC_ARCH_RISCV (243 << 16)
|
|
#define KEXEC_ARCH_LOONGARCH (258 << 16)
|
|
|
|
/* The artificial cap on the number of segments passed to kexec_load. */
|
|
#define KEXEC_SEGMENT_MAX 16
|
|
|
|
#ifndef __KERNEL__
|
|
/*
|
|
* This structure is used to hold the arguments that are used when
|
|
* loading kernel binaries.
|
|
*/
|
|
struct kexec_segment {
|
|
const void *buf;
|
|
__kernel_size_t bufsz;
|
|
const void *mem;
|
|
__kernel_size_t memsz;
|
|
};
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* _UAPILINUX_KEXEC_H */
|