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Diffstat (limited to 'man2/kexec_load.2')
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diff --git a/man2/kexec_load.2 b/man2/kexec_load.2 deleted file mode 100644 index 499f6ca..0000000 --- a/man2/kexec_load.2 +++ /dev/null @@ -1,331 +0,0 @@ -.\" Copyright (C) 2010 Intel Corporation, Author: Andi Kleen -.\" and Copyright 2014, Vivek Goyal <vgoyal@redhat.com> -.\" and Copyright (c) 2015, Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH kexec_load 2 2023-10-31 "Linux man-pages 6.7" -.SH NAME -kexec_load, kexec_file_load \- load a new kernel for later execution -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.BR "#include <linux/kexec.h>" " /* Definition of " KEXEC_* " constants */" -.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" -.B #include <unistd.h> -.P -.BI "long syscall(SYS_kexec_load, unsigned long " entry , -.BI " unsigned long " nr_segments \ -", struct kexec_segment *" segments , -.BI " unsigned long " flags ); -.BI "long syscall(SYS_kexec_file_load, int " kernel_fd ", int " initrd_fd , -.BI " unsigned long " cmdline_len ", const char *" cmdline , -.BI " unsigned long " flags ); -.fi -.P -.IR Note : -glibc provides no wrappers for these system calls, -necessitating the use of -.BR syscall (2). -.SH DESCRIPTION -The -.BR kexec_load () -system call loads a new kernel that can be executed later by -.BR reboot (2). -.P -The -.I flags -argument is a bit mask that controls the operation of the call. -The following values can be specified in -.IR flags : -.TP -.BR KEXEC_ON_CRASH " (since Linux 2.6.13)" -Execute the new kernel automatically on a system crash. -This "crash kernel" is loaded into an area of reserved memory that -is determined at boot time using the -.I crashkernel -kernel command-line parameter. -The location of this reserved memory is exported to user space via the -.I /proc/iomem -file, in an entry labeled "Crash kernel". -A user-space application can parse this file and prepare a list of -segments (see below) that specify this reserved memory as destination. -If this flag is specified, the kernel checks that the -target segments specified in -.I segments -fall within the reserved region. -.TP -.BR KEXEC_PRESERVE_CONTEXT " (since Linux 2.6.27)" -Preserve the system hardware and -software states before executing the new kernel. -This could be used for system suspend. -This flag is available only if the kernel was configured with -.BR CONFIG_KEXEC_JUMP , -and is effective only if -.I nr_segments -is greater than 0. -.P -The high-order bits (corresponding to the mask 0xffff0000) of -.I flags -contain the architecture of the to-be-executed kernel. -Specify (OR) the constant -.B KEXEC_ARCH_DEFAULT -to use the current architecture, -or one of the following architecture constants -.BR KEXEC_ARCH_386 , -.BR KEXEC_ARCH_68K , -.BR KEXEC_ARCH_X86_64 , -.BR KEXEC_ARCH_PPC , -.BR KEXEC_ARCH_PPC64 , -.BR KEXEC_ARCH_IA_64 , -.BR KEXEC_ARCH_ARM , -.BR KEXEC_ARCH_S390 , -.BR KEXEC_ARCH_SH , -.BR KEXEC_ARCH_MIPS , -and -.BR KEXEC_ARCH_MIPS_LE . -The architecture must be executable on the CPU of the system. -.P -The -.I entry -argument is the physical entry address in the kernel image. -The -.I nr_segments -argument is the number of segments pointed to by the -.I segments -pointer; -the kernel imposes an (arbitrary) limit of 16 on the number of segments. -The -.I segments -argument is an array of -.I kexec_segment -structures which define the kernel layout: -.P -.in +4n -.EX -struct kexec_segment { - void *buf; /* Buffer in user space */ - size_t bufsz; /* Buffer length in user space */ - void *mem; /* Physical address of kernel */ - size_t memsz; /* Physical address length */ -}; -.EE -.in -.P -The kernel image defined by -.I segments -is copied from the calling process into -the kernel either in regular -memory or in reserved memory (if -.B KEXEC_ON_CRASH -is set). -The kernel first performs various sanity checks on the -information passed in -.IR segments . -If these checks pass, the kernel copies the segment data to kernel memory. -Each segment specified in -.I segments -is copied as follows: -.IP \[bu] 3 -.I buf -and -.I bufsz -identify a memory region in the caller's virtual address space -that is the source of the copy. -The value in -.I bufsz -may not exceed the value in the -.I memsz -field. -.IP \[bu] -.I mem -and -.I memsz -specify a physical address range that is the target of the copy. -The values specified in both fields must be multiples of -the system page size. -.IP \[bu] -.I bufsz -bytes are copied from the source buffer to the target kernel buffer. -If -.I bufsz -is less than -.IR memsz , -then the excess bytes in the kernel buffer are zeroed out. -.P -In case of a normal kexec (i.e., the -.B KEXEC_ON_CRASH -flag is not set), the segment data is loaded in any available memory -and is moved to the final destination at kexec reboot time (e.g., when the -.BR kexec (8) -command is executed with the -.I \-e -option). -.P -In case of kexec on panic (i.e., the -.B KEXEC_ON_CRASH -flag is set), the segment data is -loaded to reserved memory at the time of the call, and, after a crash, -the kexec mechanism simply passes control to that kernel. -.P -The -.BR kexec_load () -system call is available only if the kernel was configured with -.BR CONFIG_KEXEC . -.SS kexec_file_load() -The -.BR kexec_file_load () -system call is similar to -.BR kexec_load (), -but it takes a different set of arguments. -It reads the kernel to be loaded from the file referred to by -the file descriptor -.IR kernel_fd , -and the initrd (initial RAM disk) -to be loaded from file referred to by the file descriptor -.IR initrd_fd . -The -.I cmdline -argument is a pointer to a buffer containing the command line -for the new kernel. -The -.I cmdline_len -argument specifies size of the buffer. -The last byte in the buffer must be a null byte (\[aq]\e0\[aq]). -.P -The -.I flags -argument is a bit mask which modifies the behavior of the call. -The following values can be specified in -.IR flags : -.TP -.B KEXEC_FILE_UNLOAD -Unload the currently loaded kernel. -.TP -.B KEXEC_FILE_ON_CRASH -Load the new kernel in the memory region reserved for the crash kernel -(as for -.BR KEXEC_ON_CRASH ). -This kernel is booted if the currently running kernel crashes. -.TP -.B KEXEC_FILE_NO_INITRAMFS -Loading initrd/initramfs is optional. -Specify this flag if no initramfs is being loaded. -If this flag is set, the value passed in -.I initrd_fd -is ignored. -.P -The -.BR kexec_file_load () -.\" See also http://lwn.net/Articles/603116/ -system call was added to provide support for systems -where "kexec" loading should be restricted to -only kernels that are signed. -This system call is available only if the kernel was configured with -.BR CONFIG_KEXEC_FILE . -.SH RETURN VALUE -On success, these system calls returns 0. -On error, \-1 is returned and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EADDRNOTAVAIL -.\" See kernel/kexec.::sanity_check_segment_list in the 3.19 kernel source -The -.B KEXEC_ON_CRASH -flags was specified, but the region specified by the -.I mem -and -.I memsz -fields of one of the -.I segments -entries lies outside the range of memory reserved for the crash kernel. -.TP -.B EADDRNOTAVAIL -The value in a -.I mem -or -.I memsz -field in one of the -.I segments -entries is not a multiple of the system page size. -.TP -.B EBADF -.I kernel_fd -or -.I initrd_fd -is not a valid file descriptor. -.TP -.B EBUSY -Another crash kernel is already being loaded -or a crash kernel is already in use. -.TP -.B EINVAL -.I flags -is invalid. -.TP -.B EINVAL -The value of a -.I bufsz -field in one of the -.I segments -entries exceeds the value in the corresponding -.I memsz -field. -.TP -.B EINVAL -.I nr_segments -exceeds -.B KEXEC_SEGMENT_MAX -(16). -.TP -.B EINVAL -Two or more of the kernel target buffers overlap. -.TP -.B EINVAL -The value in -.I cmdline[cmdline_len\-1] -is not \[aq]\e0\[aq]. -.TP -.B EINVAL -The file referred to by -.I kernel_fd -or -.I initrd_fd -is empty (length zero). -.TP -.B ENOEXEC -.I kernel_fd -does not refer to an open file, or the kernel can't load this file. -Currently, the file must be a bzImage and contain an x86 kernel that -is loadable above 4\ GiB in memory (see the kernel source file -.IR Documentation/x86/boot.txt ). -.TP -.B ENOMEM -Could not allocate memory. -.TP -.B EPERM -The caller does not have the -.B CAP_SYS_BOOT -capability. -.SH STANDARDS -Linux. -.SH HISTORY -.TP -.BR kexec_load () -Linux 2.6.13. -.TP -.BR kexec_file_load () -Linux 3.17. -.SH SEE ALSO -.BR reboot (2), -.BR syscall (2), -.BR kexec (8) -.P -The kernel source files -.I Documentation/kdump/kdump.txt -and -.I Documentation/admin\-guide/kernel\-parameters.txt |