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The kernel cmdline length is allowed to be longer than what printk can handle. When this happens the cmdline that's printed to the kernel ring buffer at bootup is cutoff and some kernel cmdline options are "hidden" from the logs. This undercuts the usefulness of the log message. Specifically, grepping for COMMAND_LINE_SIZE shows that 2048 is common and some architectures even define it as 4096. s390 allows a CONFIG-based maximum up to 1MB (though it's not expected that anyone will go over the default max of 4096 [1]). The maximum message pr_notice() seems to be able to handle (based on experiment) is 1021 characters. This appears to be based on the current value of PRINTKRB_RECORD_MAX as 1024 and the fact that pr_notice() spends 2 characters on the loglevel prefix and we have a '\n' at the end. While it would be possible to increase the limits of printk() (and therefore pr_notice()) somewhat, it doesn't appear possible to increase it enough to fully include a 2048-character cmdline without breaking userspace. Specifically on at least two tested userspaces (ChromeOS plus the Debian-based distro I'm typing this message on) the `dmesg` tool reads lines from `/dev/kmsg` in 2047-byte chunks. As per `Documentation/ABI/testing/dev-kmsg`: Every read() from the opened device node receives one record of the kernel's printk buffer. ... Messages in the record ring buffer get overwritten as whole, there are never partial messages received by read(). We simply can't fit a 2048-byte cmdline plus the "Kernel command line:" prefix plus info about time/log_level/etc in a 2047-byte read. The above means that if we want to avoid the truncation we need to do some type of wrapping of the cmdline when printing. Add wrapping to the printout of the kernel command line. By default, the wrapping is set to 1021 characters to avoid breaking anyone, but allow wrapping to be set lower by a Kconfig knob "CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN". Any tools that are correctly parsing the cmdline today (because it is less than 1021 characters) will see no difference in their behavior. The format of wrapped output is designed to be matched by anyone using "grep" to search for the cmdline and also to be easy for tools to handle. Anyone who is sure their tools (if any) handle the wrapped format can choose a lower wrapping value and have prettier output. Setting CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN to 0 fully disables the wrapping logic. This means that long command lines will be truncated again, but this config could be set if command lines are expected to be long and userspace is known not to handle parsing logs with the wrapping. Wrapping is based on spaces, ignoring quotes. All lines are prefixed with "Kernel command line: " and lines that are not the last line have a " \" suffix added to them. The prefix and suffix count towards the line length for wrapping purposes. The ideal length will be exceeded if no appropriate place to wrap is found. The wrapping function added here is fairly generic and could be made a library function (somewhat like print_hex_dump()) if it's needed elsewhere in the kernel. However, having printk() directly incorporate this wrapping would be unlikely to be a good idea since it would break printouts into more than one record without any obvious common line prefix to tie lines together. It would also be extra overhead when, in general, kernel log message should simply be kept smaller than 1021 bytes. For some discussion on this topic, see responses to the v1 posting of this patch [2]. [akpm@linux-foundation.org: make print_kernel_cmdline __init] [dianders@chromium.org: v4] Link: https://lkml.kernel.org/r/20251027082204.v4.1.I095f1e2c6c27f9f4de0b4841f725f356c643a13f@changeid Link: https://lkml.kernel.org/r/20251023113257.v3.1.I095f1e2c6c27f9f4de0b4841f725f356c643a13f@changeid Link: https://lore.kernel.org/r/20251021131633.26700Dd6-hca@linux.ibm.com [1] Link: https://lore.kernel.org/r/CAD=FV=VNyt1zG_8pS64wgV8VkZWiWJymnZ-XCfkrfaAhhFSKcA@mail.gmail.com [2] Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Chant <achant@google.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Francesco Valla <francesco@valla.it> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: guoweikang <guoweikang.kernel@gmail.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Hendrik Farr <kernel@jfarr.cc> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Kees Cook <kees@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1719 lines
42 KiB
C
1719 lines
42 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/init/main.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* GK 2/5/95 - Changed to support mounting root fs via NFS
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* Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
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* Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
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* Simplified starting of init: Michael A. Griffith <grif@acm.org>
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*/
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#define DEBUG /* Enable initcall_debug */
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#include <linux/types.h>
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#include <linux/export.h>
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#include <linux/extable.h>
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#include <linux/module.h>
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#include <linux/proc_fs.h>
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#include <linux/binfmts.h>
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#include <linux/kernel.h>
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#include <linux/syscalls.h>
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#include <linux/stackprotector.h>
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#include <linux/string.h>
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#include <linux/ctype.h>
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#include <linux/delay.h>
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#include <linux/ioport.h>
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#include <linux/init.h>
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#include <linux/initrd.h>
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#include <linux/memblock.h>
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#include <linux/acpi.h>
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#include <linux/bootconfig.h>
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#include <linux/console.h>
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#include <linux/nmi.h>
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#include <linux/percpu.h>
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#include <linux/kmod.h>
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#include <linux/kprobes.h>
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#include <linux/kmsan.h>
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#include <linux/vmalloc.h>
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#include <linux/kernel_stat.h>
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#include <linux/start_kernel.h>
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#include <linux/security.h>
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#include <linux/smp.h>
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#include <linux/profile.h>
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#include <linux/kfence.h>
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#include <linux/rcupdate.h>
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#include <linux/srcu.h>
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#include <linux/moduleparam.h>
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#include <linux/kallsyms.h>
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#include <linux/buildid.h>
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#include <linux/writeback.h>
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#include <linux/cpu.h>
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#include <linux/cpuset.h>
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#include <linux/memcontrol.h>
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#include <linux/cgroup.h>
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#include <linux/tick.h>
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#include <linux/sched/isolation.h>
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#include <linux/interrupt.h>
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#include <linux/taskstats_kern.h>
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#include <linux/delayacct.h>
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#include <linux/unistd.h>
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#include <linux/utsname.h>
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#include <linux/rmap.h>
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#include <linux/mempolicy.h>
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#include <linux/key.h>
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#include <linux/debug_locks.h>
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#include <linux/debugobjects.h>
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#include <linux/lockdep.h>
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#include <linux/kmemleak.h>
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#include <linux/padata.h>
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#include <linux/pid_namespace.h>
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#include <linux/device/driver.h>
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#include <linux/kthread.h>
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#include <linux/sched.h>
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#include <linux/sched/init.h>
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#include <linux/signal.h>
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#include <linux/idr.h>
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#include <linux/kgdb.h>
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#include <linux/ftrace.h>
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#include <linux/async.h>
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#include <linux/shmem_fs.h>
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#include <linux/slab.h>
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#include <linux/perf_event.h>
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#include <linux/ptrace.h>
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#include <linux/pti.h>
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#include <linux/blkdev.h>
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#include <linux/sched/clock.h>
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#include <linux/sched/task.h>
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#include <linux/sched/task_stack.h>
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#include <linux/context_tracking.h>
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#include <linux/random.h>
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#include <linux/moduleloader.h>
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#include <linux/list.h>
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#include <linux/integrity.h>
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#include <linux/proc_ns.h>
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#include <linux/io.h>
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#include <linux/cache.h>
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#include <linux/rodata_test.h>
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#include <linux/jump_label.h>
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#include <linux/kcsan.h>
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#include <linux/init_syscalls.h>
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#include <linux/stackdepot.h>
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#include <linux/randomize_kstack.h>
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#include <linux/pidfs.h>
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#include <linux/ptdump.h>
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#include <linux/time_namespace.h>
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#include <net/net_namespace.h>
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#include <asm/io.h>
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#include <asm/setup.h>
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#include <asm/sections.h>
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#include <asm/cacheflush.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/initcall.h>
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#include <kunit/test.h>
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static int kernel_init(void *);
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/*
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* Debug helper: via this flag we know that we are in 'early bootup code'
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* where only the boot processor is running with IRQ disabled. This means
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* two things - IRQ must not be enabled before the flag is cleared and some
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* operations which are not allowed with IRQ disabled are allowed while the
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* flag is set.
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*/
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bool early_boot_irqs_disabled __read_mostly;
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enum system_states system_state __read_mostly;
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EXPORT_SYMBOL(system_state);
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/*
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* Boot command-line arguments
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*/
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#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
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#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
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/* Default late time init is NULL. archs can override this later. */
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void (*__initdata late_time_init)(void);
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/* Untouched command line saved by arch-specific code. */
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char __initdata boot_command_line[COMMAND_LINE_SIZE];
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/* Untouched saved command line (eg. for /proc) */
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char *saved_command_line __ro_after_init;
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unsigned int saved_command_line_len __ro_after_init;
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/* Command line for parameter parsing */
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static char *static_command_line;
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/* Untouched extra command line */
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static char *extra_command_line;
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/* Extra init arguments */
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static char *extra_init_args;
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#ifdef CONFIG_BOOT_CONFIG
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/* Is bootconfig on command line? */
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static bool bootconfig_found;
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static size_t initargs_offs;
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#else
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# define bootconfig_found false
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# define initargs_offs 0
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#endif
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static char *execute_command;
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static char *ramdisk_execute_command = "/init";
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/*
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* Used to generate warnings if static_key manipulation functions are used
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* before jump_label_init is called.
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*/
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bool static_key_initialized __read_mostly;
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EXPORT_SYMBOL_GPL(static_key_initialized);
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/*
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* If set, this is an indication to the drivers that reset the underlying
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* device before going ahead with the initialization otherwise driver might
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* rely on the BIOS and skip the reset operation.
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*
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* This is useful if kernel is booting in an unreliable environment.
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* For ex. kdump situation where previous kernel has crashed, BIOS has been
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* skipped and devices will be in unknown state.
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*/
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unsigned int reset_devices;
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EXPORT_SYMBOL(reset_devices);
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static int __init set_reset_devices(char *str)
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{
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reset_devices = 1;
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return 1;
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}
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__setup("reset_devices", set_reset_devices);
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static const char *argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
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const char *envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
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static const char *panic_later, *panic_param;
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static bool __init obsolete_checksetup(char *line)
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{
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const struct obs_kernel_param *p;
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bool had_early_param = false;
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p = __setup_start;
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do {
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int n = strlen(p->str);
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if (parameqn(line, p->str, n)) {
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if (p->early) {
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/* Already done in parse_early_param?
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* (Needs exact match on param part).
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* Keep iterating, as we can have early
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* params and __setups of same names 8( */
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if (line[n] == '\0' || line[n] == '=')
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had_early_param = true;
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} else if (!p->setup_func) {
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pr_warn("Parameter %s is obsolete, ignored\n",
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p->str);
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return true;
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} else if (p->setup_func(line + n))
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return true;
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}
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p++;
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} while (p < __setup_end);
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return had_early_param;
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}
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/*
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* This should be approx 2 Bo*oMips to start (note initial shift), and will
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* still work even if initially too large, it will just take slightly longer
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*/
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unsigned long loops_per_jiffy = (1<<12);
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EXPORT_SYMBOL(loops_per_jiffy);
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static int __init debug_kernel(char *str)
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{
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console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
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return 0;
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}
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static int __init quiet_kernel(char *str)
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{
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console_loglevel = CONSOLE_LOGLEVEL_QUIET;
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return 0;
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}
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early_param("debug", debug_kernel);
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early_param("quiet", quiet_kernel);
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static int __init loglevel(char *str)
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{
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int newlevel;
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/*
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* Only update loglevel value when a correct setting was passed,
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* to prevent blind crashes (when loglevel being set to 0) that
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* are quite hard to debug
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*/
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if (get_option(&str, &newlevel)) {
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console_loglevel = newlevel;
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return 0;
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}
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return -EINVAL;
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}
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early_param("loglevel", loglevel);
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#ifdef CONFIG_BLK_DEV_INITRD
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static void * __init get_boot_config_from_initrd(size_t *_size)
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{
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u32 size, csum;
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char *data;
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u32 *hdr;
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int i;
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if (!initrd_end)
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return NULL;
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data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN;
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/*
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* Since Grub may align the size of initrd to 4, we must
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* check the preceding 3 bytes as well.
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*/
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for (i = 0; i < 4; i++) {
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if (!memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN))
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goto found;
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data--;
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}
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return NULL;
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found:
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hdr = (u32 *)(data - 8);
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size = le32_to_cpu(hdr[0]);
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csum = le32_to_cpu(hdr[1]);
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data = ((void *)hdr) - size;
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if ((unsigned long)data < initrd_start) {
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pr_err("bootconfig size %d is greater than initrd size %ld\n",
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size, initrd_end - initrd_start);
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return NULL;
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}
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if (xbc_calc_checksum(data, size) != csum) {
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pr_err("bootconfig checksum failed\n");
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return NULL;
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}
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/* Remove bootconfig from initramfs/initrd */
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initrd_end = (unsigned long)data;
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if (_size)
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*_size = size;
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return data;
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}
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#else
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static void * __init get_boot_config_from_initrd(size_t *_size)
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{
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return NULL;
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}
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#endif
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#ifdef CONFIG_BOOT_CONFIG
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static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata;
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#define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0)
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static int __init xbc_snprint_cmdline(char *buf, size_t size,
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struct xbc_node *root)
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{
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struct xbc_node *knode, *vnode;
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char *end = buf + size;
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const char *val, *q;
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int ret;
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xbc_node_for_each_key_value(root, knode, val) {
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ret = xbc_node_compose_key_after(root, knode,
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xbc_namebuf, XBC_KEYLEN_MAX);
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if (ret < 0)
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return ret;
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vnode = xbc_node_get_child(knode);
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if (!vnode) {
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ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf);
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if (ret < 0)
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return ret;
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buf += ret;
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continue;
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}
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xbc_array_for_each_value(vnode, val) {
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/*
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* For prettier and more readable /proc/cmdline, only
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* quote the value when necessary, i.e. when it contains
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* whitespace.
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*/
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q = strpbrk(val, " \t\r\n") ? "\"" : "";
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ret = snprintf(buf, rest(buf, end), "%s=%s%s%s ",
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xbc_namebuf, q, val, q);
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if (ret < 0)
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return ret;
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buf += ret;
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}
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}
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return buf - (end - size);
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}
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#undef rest
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/* Make an extra command line under given key word */
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static char * __init xbc_make_cmdline(const char *key)
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{
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struct xbc_node *root;
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char *new_cmdline;
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int ret, len = 0;
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root = xbc_find_node(key);
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if (!root)
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return NULL;
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/* Count required buffer size */
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len = xbc_snprint_cmdline(NULL, 0, root);
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if (len <= 0)
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return NULL;
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new_cmdline = memblock_alloc(len + 1, SMP_CACHE_BYTES);
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if (!new_cmdline) {
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pr_err("Failed to allocate memory for extra kernel cmdline.\n");
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return NULL;
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}
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ret = xbc_snprint_cmdline(new_cmdline, len + 1, root);
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if (ret < 0 || ret > len) {
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pr_err("Failed to print extra kernel cmdline.\n");
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memblock_free(new_cmdline, len + 1);
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return NULL;
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}
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return new_cmdline;
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}
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static int __init bootconfig_params(char *param, char *val,
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const char *unused, void *arg)
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{
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if (strcmp(param, "bootconfig") == 0) {
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bootconfig_found = true;
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}
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return 0;
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}
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static int __init warn_bootconfig(char *str)
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{
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/* The 'bootconfig' has been handled by bootconfig_params(). */
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return 0;
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}
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static void __init setup_boot_config(void)
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{
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static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
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const char *msg, *data;
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int pos, ret;
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size_t size;
|
|
char *err;
|
|
|
|
/* Cut out the bootconfig data even if we have no bootconfig option */
|
|
data = get_boot_config_from_initrd(&size);
|
|
/* If there is no bootconfig in initrd, try embedded one. */
|
|
if (!data)
|
|
data = xbc_get_embedded_bootconfig(&size);
|
|
|
|
strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
|
|
err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
|
|
bootconfig_params);
|
|
|
|
if (IS_ERR(err) || !(bootconfig_found || IS_ENABLED(CONFIG_BOOT_CONFIG_FORCE)))
|
|
return;
|
|
|
|
/* parse_args() stops at the next param of '--' and returns an address */
|
|
if (err)
|
|
initargs_offs = err - tmp_cmdline;
|
|
|
|
if (!data) {
|
|
/* If user intended to use bootconfig, show an error level message */
|
|
if (bootconfig_found)
|
|
pr_err("'bootconfig' found on command line, but no bootconfig found\n");
|
|
else
|
|
pr_info("No bootconfig data provided, so skipping bootconfig");
|
|
return;
|
|
}
|
|
|
|
if (size >= XBC_DATA_MAX) {
|
|
pr_err("bootconfig size %ld greater than max size %d\n",
|
|
(long)size, XBC_DATA_MAX);
|
|
return;
|
|
}
|
|
|
|
ret = xbc_init(data, size, &msg, &pos);
|
|
if (ret < 0) {
|
|
if (pos < 0)
|
|
pr_err("Failed to init bootconfig: %s.\n", msg);
|
|
else
|
|
pr_err("Failed to parse bootconfig: %s at %d.\n",
|
|
msg, pos);
|
|
} else {
|
|
xbc_get_info(&ret, NULL);
|
|
pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret);
|
|
/* keys starting with "kernel." are passed via cmdline */
|
|
extra_command_line = xbc_make_cmdline("kernel");
|
|
/* Also, "init." keys are init arguments */
|
|
extra_init_args = xbc_make_cmdline("init");
|
|
}
|
|
return;
|
|
}
|
|
|
|
static void __init exit_boot_config(void)
|
|
{
|
|
xbc_exit();
|
|
}
|
|
|
|
#else /* !CONFIG_BOOT_CONFIG */
|
|
|
|
static void __init setup_boot_config(void)
|
|
{
|
|
/* Remove bootconfig data from initrd */
|
|
get_boot_config_from_initrd(NULL);
|
|
}
|
|
|
|
static int __init warn_bootconfig(char *str)
|
|
{
|
|
pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOT_CONFIG is not set.\n");
|
|
return 0;
|
|
}
|
|
|
|
#define exit_boot_config() do {} while (0)
|
|
|
|
#endif /* CONFIG_BOOT_CONFIG */
|
|
|
|
early_param("bootconfig", warn_bootconfig);
|
|
|
|
bool __init cmdline_has_extra_options(void)
|
|
{
|
|
return extra_command_line || extra_init_args;
|
|
}
|
|
|
|
/* Change NUL term back to "=", to make "param" the whole string. */
|
|
static void __init repair_env_string(char *param, char *val)
|
|
{
|
|
if (val) {
|
|
/* param=val or param="val"? */
|
|
if (val == param+strlen(param)+1)
|
|
val[-1] = '=';
|
|
else if (val == param+strlen(param)+2) {
|
|
val[-2] = '=';
|
|
memmove(val-1, val, strlen(val)+1);
|
|
} else
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
/* Anything after -- gets handed straight to init. */
|
|
static int __init set_init_arg(char *param, char *val,
|
|
const char *unused, void *arg)
|
|
{
|
|
unsigned int i;
|
|
|
|
if (panic_later)
|
|
return 0;
|
|
|
|
repair_env_string(param, val);
|
|
|
|
for (i = 0; argv_init[i]; i++) {
|
|
if (i == MAX_INIT_ARGS) {
|
|
panic_later = "init";
|
|
panic_param = param;
|
|
return 0;
|
|
}
|
|
}
|
|
argv_init[i] = param;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Unknown boot options get handed to init, unless they look like
|
|
* unused parameters (modprobe will find them in /proc/cmdline).
|
|
*/
|
|
static int __init unknown_bootoption(char *param, char *val,
|
|
const char *unused, void *arg)
|
|
{
|
|
size_t len = strlen(param);
|
|
/*
|
|
* Well-known bootloader identifiers:
|
|
* 1. LILO/Grub pass "BOOT_IMAGE=...";
|
|
* 2. kexec/kdump (kexec-tools) pass "kexec".
|
|
*/
|
|
const char *bootloader[] = { "BOOT_IMAGE=", "kexec", NULL };
|
|
|
|
/* Handle params aliased to sysctls */
|
|
if (sysctl_is_alias(param))
|
|
return 0;
|
|
|
|
repair_env_string(param, val);
|
|
|
|
/* Handle bootloader identifier */
|
|
for (int i = 0; bootloader[i]; i++) {
|
|
if (strstarts(param, bootloader[i]))
|
|
return 0;
|
|
}
|
|
|
|
/* Handle obsolete-style parameters */
|
|
if (obsolete_checksetup(param))
|
|
return 0;
|
|
|
|
/* Unused module parameter. */
|
|
if (strnchr(param, len, '.'))
|
|
return 0;
|
|
|
|
if (panic_later)
|
|
return 0;
|
|
|
|
if (val) {
|
|
/* Environment option */
|
|
unsigned int i;
|
|
for (i = 0; envp_init[i]; i++) {
|
|
if (i == MAX_INIT_ENVS) {
|
|
panic_later = "env";
|
|
panic_param = param;
|
|
}
|
|
if (!strncmp(param, envp_init[i], len+1))
|
|
break;
|
|
}
|
|
envp_init[i] = param;
|
|
} else {
|
|
/* Command line option */
|
|
unsigned int i;
|
|
for (i = 0; argv_init[i]; i++) {
|
|
if (i == MAX_INIT_ARGS) {
|
|
panic_later = "init";
|
|
panic_param = param;
|
|
}
|
|
}
|
|
argv_init[i] = param;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __init init_setup(char *str)
|
|
{
|
|
unsigned int i;
|
|
|
|
execute_command = str;
|
|
/*
|
|
* In case LILO is going to boot us with default command line,
|
|
* it prepends "auto" before the whole cmdline which makes
|
|
* the shell think it should execute a script with such name.
|
|
* So we ignore all arguments entered _before_ init=... [MJ]
|
|
*/
|
|
for (i = 1; i < MAX_INIT_ARGS; i++)
|
|
argv_init[i] = NULL;
|
|
return 1;
|
|
}
|
|
__setup("init=", init_setup);
|
|
|
|
static int __init rdinit_setup(char *str)
|
|
{
|
|
unsigned int i;
|
|
|
|
ramdisk_execute_command = str;
|
|
/* See "auto" comment in init_setup */
|
|
for (i = 1; i < MAX_INIT_ARGS; i++)
|
|
argv_init[i] = NULL;
|
|
return 1;
|
|
}
|
|
__setup("rdinit=", rdinit_setup);
|
|
|
|
#ifndef CONFIG_SMP
|
|
static inline void setup_nr_cpu_ids(void) { }
|
|
static inline void smp_prepare_cpus(unsigned int maxcpus) { }
|
|
#endif
|
|
|
|
/*
|
|
* We need to store the untouched command line for future reference.
|
|
* We also need to store the touched command line since the parameter
|
|
* parsing is performed in place, and we should allow a component to
|
|
* store reference of name/value for future reference.
|
|
*/
|
|
static void __init setup_command_line(char *command_line)
|
|
{
|
|
size_t len, xlen = 0, ilen = 0;
|
|
|
|
if (extra_command_line)
|
|
xlen = strlen(extra_command_line);
|
|
if (extra_init_args) {
|
|
extra_init_args = strim(extra_init_args); /* remove trailing space */
|
|
ilen = strlen(extra_init_args) + 4; /* for " -- " */
|
|
}
|
|
|
|
len = xlen + strlen(boot_command_line) + ilen + 1;
|
|
|
|
saved_command_line = memblock_alloc_or_panic(len, SMP_CACHE_BYTES);
|
|
|
|
len = xlen + strlen(command_line) + 1;
|
|
|
|
static_command_line = memblock_alloc_or_panic(len, SMP_CACHE_BYTES);
|
|
|
|
if (xlen) {
|
|
/*
|
|
* We have to put extra_command_line before boot command
|
|
* lines because there could be dashes (separator of init
|
|
* command line) in the command lines.
|
|
*/
|
|
strcpy(saved_command_line, extra_command_line);
|
|
strcpy(static_command_line, extra_command_line);
|
|
}
|
|
strcpy(saved_command_line + xlen, boot_command_line);
|
|
strcpy(static_command_line + xlen, command_line);
|
|
|
|
if (ilen) {
|
|
/*
|
|
* Append supplemental init boot args to saved_command_line
|
|
* so that user can check what command line options passed
|
|
* to init.
|
|
* The order should always be
|
|
* " -- "[bootconfig init-param][cmdline init-param]
|
|
*/
|
|
if (initargs_offs) {
|
|
len = xlen + initargs_offs;
|
|
strcpy(saved_command_line + len, extra_init_args);
|
|
len += ilen - 4; /* strlen(extra_init_args) */
|
|
strcpy(saved_command_line + len,
|
|
boot_command_line + initargs_offs - 1);
|
|
} else {
|
|
len = strlen(saved_command_line);
|
|
strcpy(saved_command_line + len, " -- ");
|
|
len += 4;
|
|
strcpy(saved_command_line + len, extra_init_args);
|
|
}
|
|
}
|
|
|
|
saved_command_line_len = strlen(saved_command_line);
|
|
}
|
|
|
|
/*
|
|
* We need to finalize in a non-__init function or else race conditions
|
|
* between the root thread and the init thread may cause start_kernel to
|
|
* be reaped by free_initmem before the root thread has proceeded to
|
|
* cpu_idle.
|
|
*
|
|
* gcc-3.4 accidentally inlines this function, so use noinline.
|
|
*/
|
|
|
|
static __initdata DECLARE_COMPLETION(kthreadd_done);
|
|
|
|
static noinline void __ref __noreturn rest_init(void)
|
|
{
|
|
struct task_struct *tsk;
|
|
int pid;
|
|
|
|
rcu_scheduler_starting();
|
|
/*
|
|
* We need to spawn init first so that it obtains pid 1, however
|
|
* the init task will end up wanting to create kthreads, which, if
|
|
* we schedule it before we create kthreadd, will OOPS.
|
|
*/
|
|
pid = user_mode_thread(kernel_init, NULL, CLONE_FS);
|
|
/*
|
|
* Pin init on the boot CPU. Task migration is not properly working
|
|
* until sched_init_smp() has been run. It will set the allowed
|
|
* CPUs for init to the non isolated CPUs.
|
|
*/
|
|
rcu_read_lock();
|
|
tsk = find_task_by_pid_ns(pid, &init_pid_ns);
|
|
tsk->flags |= PF_NO_SETAFFINITY;
|
|
set_cpus_allowed_ptr(tsk, cpumask_of(smp_processor_id()));
|
|
rcu_read_unlock();
|
|
|
|
numa_default_policy();
|
|
pid = kernel_thread(kthreadd, NULL, NULL, CLONE_FS | CLONE_FILES);
|
|
rcu_read_lock();
|
|
kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
|
|
rcu_read_unlock();
|
|
|
|
/*
|
|
* Enable might_sleep() and smp_processor_id() checks.
|
|
* They cannot be enabled earlier because with CONFIG_PREEMPTION=y
|
|
* kernel_thread() would trigger might_sleep() splats. With
|
|
* CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled
|
|
* already, but it's stuck on the kthreadd_done completion.
|
|
*/
|
|
system_state = SYSTEM_SCHEDULING;
|
|
|
|
complete(&kthreadd_done);
|
|
|
|
/*
|
|
* The boot idle thread must execute schedule()
|
|
* at least once to get things moving:
|
|
*/
|
|
schedule_preempt_disabled();
|
|
/* Call into cpu_idle with preempt disabled */
|
|
cpu_startup_entry(CPUHP_ONLINE);
|
|
}
|
|
|
|
/* Check for early params. */
|
|
static int __init do_early_param(char *param, char *val,
|
|
const char *unused, void *arg)
|
|
{
|
|
const struct obs_kernel_param *p;
|
|
|
|
for (p = __setup_start; p < __setup_end; p++) {
|
|
if (p->early && parameq(param, p->str)) {
|
|
if (p->setup_func(val) != 0)
|
|
pr_warn("Malformed early option '%s'\n", param);
|
|
}
|
|
}
|
|
/* We accept everything at this stage. */
|
|
return 0;
|
|
}
|
|
|
|
void __init parse_early_options(char *cmdline)
|
|
{
|
|
parse_args("early options", cmdline, NULL, 0, 0, 0, NULL,
|
|
do_early_param);
|
|
}
|
|
|
|
/* Arch code calls this early on, or if not, just before other parsing. */
|
|
void __init parse_early_param(void)
|
|
{
|
|
static int done __initdata;
|
|
static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
|
|
|
|
if (done)
|
|
return;
|
|
|
|
/* All fall through to do_early_param. */
|
|
strscpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
|
|
parse_early_options(tmp_cmdline);
|
|
done = 1;
|
|
}
|
|
|
|
void __init __weak arch_post_acpi_subsys_init(void) { }
|
|
|
|
void __init __weak smp_setup_processor_id(void)
|
|
{
|
|
}
|
|
|
|
void __init __weak smp_prepare_boot_cpu(void)
|
|
{
|
|
}
|
|
|
|
# if THREAD_SIZE >= PAGE_SIZE
|
|
void __init __weak thread_stack_cache_init(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
void __init __weak poking_init(void) { }
|
|
|
|
void __init __weak pgtable_cache_init(void) { }
|
|
|
|
void __init __weak trap_init(void) { }
|
|
|
|
bool initcall_debug;
|
|
core_param(initcall_debug, initcall_debug, bool, 0644);
|
|
|
|
#ifdef TRACEPOINTS_ENABLED
|
|
static void __init initcall_debug_enable(void);
|
|
#else
|
|
static inline void initcall_debug_enable(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET
|
|
DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT,
|
|
randomize_kstack_offset);
|
|
DEFINE_PER_CPU(u32, kstack_offset);
|
|
|
|
static int __init early_randomize_kstack_offset(char *buf)
|
|
{
|
|
int ret;
|
|
bool bool_result;
|
|
|
|
ret = kstrtobool(buf, &bool_result);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (bool_result)
|
|
static_branch_enable(&randomize_kstack_offset);
|
|
else
|
|
static_branch_disable(&randomize_kstack_offset);
|
|
return 0;
|
|
}
|
|
early_param("randomize_kstack_offset", early_randomize_kstack_offset);
|
|
#endif
|
|
|
|
static void __init print_unknown_bootoptions(void)
|
|
{
|
|
char *unknown_options;
|
|
char *end;
|
|
const char *const *p;
|
|
size_t len;
|
|
|
|
if (panic_later || (!argv_init[1] && !envp_init[2]))
|
|
return;
|
|
|
|
/*
|
|
* Determine how many options we have to print out, plus a space
|
|
* before each
|
|
*/
|
|
len = 1; /* null terminator */
|
|
for (p = &argv_init[1]; *p; p++) {
|
|
len++;
|
|
len += strlen(*p);
|
|
}
|
|
for (p = &envp_init[2]; *p; p++) {
|
|
len++;
|
|
len += strlen(*p);
|
|
}
|
|
|
|
unknown_options = memblock_alloc(len, SMP_CACHE_BYTES);
|
|
if (!unknown_options) {
|
|
pr_err("%s: Failed to allocate %zu bytes\n",
|
|
__func__, len);
|
|
return;
|
|
}
|
|
end = unknown_options;
|
|
|
|
for (p = &argv_init[1]; *p; p++)
|
|
end += sprintf(end, " %s", *p);
|
|
for (p = &envp_init[2]; *p; p++)
|
|
end += sprintf(end, " %s", *p);
|
|
|
|
/* Start at unknown_options[1] to skip the initial space */
|
|
pr_notice("Unknown kernel command line parameters \"%s\", will be passed to user space.\n",
|
|
&unknown_options[1]);
|
|
memblock_free(unknown_options, len);
|
|
}
|
|
|
|
static void __init early_numa_node_init(void)
|
|
{
|
|
#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
|
|
#ifndef cpu_to_node
|
|
int cpu;
|
|
|
|
/* The early_cpu_to_node() should be ready here. */
|
|
for_each_possible_cpu(cpu)
|
|
set_cpu_numa_node(cpu, early_cpu_to_node(cpu));
|
|
#endif
|
|
#endif
|
|
}
|
|
|
|
#define KERNEL_CMDLINE_PREFIX "Kernel command line: "
|
|
#define KERNEL_CMDLINE_PREFIX_LEN (sizeof(KERNEL_CMDLINE_PREFIX) - 1)
|
|
#define KERNEL_CMDLINE_CONTINUATION " \\"
|
|
#define KERNEL_CMDLINE_CONTINUATION_LEN (sizeof(KERNEL_CMDLINE_CONTINUATION) - 1)
|
|
|
|
#define MIN_CMDLINE_LOG_WRAP_IDEAL_LEN (KERNEL_CMDLINE_PREFIX_LEN + \
|
|
KERNEL_CMDLINE_CONTINUATION_LEN)
|
|
#define CMDLINE_LOG_WRAP_IDEAL_LEN (CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN > \
|
|
MIN_CMDLINE_LOG_WRAP_IDEAL_LEN ? \
|
|
CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN : \
|
|
MIN_CMDLINE_LOG_WRAP_IDEAL_LEN)
|
|
|
|
#define IDEAL_CMDLINE_LEN (CMDLINE_LOG_WRAP_IDEAL_LEN - KERNEL_CMDLINE_PREFIX_LEN)
|
|
#define IDEAL_CMDLINE_SPLIT_LEN (IDEAL_CMDLINE_LEN - KERNEL_CMDLINE_CONTINUATION_LEN)
|
|
|
|
/**
|
|
* print_kernel_cmdline() - Print the kernel cmdline with wrapping.
|
|
* @cmdline: The cmdline to print.
|
|
*
|
|
* Print the kernel command line, trying to wrap based on the Kconfig knob
|
|
* CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN.
|
|
*
|
|
* Wrapping is based on spaces, ignoring quotes. All lines are prefixed
|
|
* with "Kernel command line: " and lines that are not the last line have
|
|
* a " \" suffix added to them. The prefix and suffix count towards the
|
|
* line length for wrapping purposes. The ideal length will be exceeded
|
|
* if no appropriate place to wrap is found.
|
|
*
|
|
* Example output if CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN is 40:
|
|
* Kernel command line: loglevel=7 \
|
|
* Kernel command line: init=/sbin/init \
|
|
* Kernel command line: root=PARTUUID=8c3efc1a-768b-6642-8d0c-89eb782f19f0/PARTNROFF=1 \
|
|
* Kernel command line: rootwait ro \
|
|
* Kernel command line: my_quoted_arg="The \
|
|
* Kernel command line: quick brown fox \
|
|
* Kernel command line: jumps over the \
|
|
* Kernel command line: lazy dog."
|
|
*/
|
|
static void __init print_kernel_cmdline(const char *cmdline)
|
|
{
|
|
size_t len;
|
|
|
|
/* Config option of 0 or anything longer than the max disables wrapping */
|
|
if (CONFIG_CMDLINE_LOG_WRAP_IDEAL_LEN == 0 ||
|
|
IDEAL_CMDLINE_LEN >= COMMAND_LINE_SIZE - 1) {
|
|
pr_notice("%s%s\n", KERNEL_CMDLINE_PREFIX, cmdline);
|
|
return;
|
|
}
|
|
|
|
len = strlen(cmdline);
|
|
while (len > IDEAL_CMDLINE_LEN) {
|
|
const char *first_space;
|
|
const char *prev_cutoff;
|
|
const char *cutoff;
|
|
int to_print;
|
|
size_t used;
|
|
|
|
/* Find the last ' ' that wouldn't make the line too long */
|
|
prev_cutoff = NULL;
|
|
cutoff = cmdline;
|
|
while (true) {
|
|
cutoff = strchr(cutoff + 1, ' ');
|
|
if (!cutoff || cutoff - cmdline > IDEAL_CMDLINE_SPLIT_LEN)
|
|
break;
|
|
prev_cutoff = cutoff;
|
|
}
|
|
if (prev_cutoff)
|
|
cutoff = prev_cutoff;
|
|
else if (!cutoff)
|
|
break;
|
|
|
|
/* Find the beginning and end of the string of spaces */
|
|
first_space = cutoff;
|
|
while (first_space > cmdline && first_space[-1] == ' ')
|
|
first_space--;
|
|
to_print = first_space - cmdline;
|
|
while (*cutoff == ' ')
|
|
cutoff++;
|
|
used = cutoff - cmdline;
|
|
|
|
/* If the whole string is used, break and do the final printout */
|
|
if (len == used)
|
|
break;
|
|
|
|
if (to_print)
|
|
pr_notice("%s%.*s%s\n", KERNEL_CMDLINE_PREFIX,
|
|
to_print, cmdline, KERNEL_CMDLINE_CONTINUATION);
|
|
|
|
len -= used;
|
|
cmdline += used;
|
|
}
|
|
if (len)
|
|
pr_notice("%s%s\n", KERNEL_CMDLINE_PREFIX, cmdline);
|
|
}
|
|
|
|
asmlinkage __visible __init __no_sanitize_address __noreturn __no_stack_protector
|
|
void start_kernel(void)
|
|
{
|
|
char *command_line;
|
|
char *after_dashes;
|
|
|
|
set_task_stack_end_magic(&init_task);
|
|
smp_setup_processor_id();
|
|
debug_objects_early_init();
|
|
init_vmlinux_build_id();
|
|
|
|
cgroup_init_early();
|
|
|
|
local_irq_disable();
|
|
early_boot_irqs_disabled = true;
|
|
|
|
/*
|
|
* Interrupts are still disabled. Do necessary setups, then
|
|
* enable them.
|
|
*/
|
|
boot_cpu_init();
|
|
page_address_init();
|
|
pr_notice("%s", linux_banner);
|
|
setup_arch(&command_line);
|
|
/* Static keys and static calls are needed by LSMs */
|
|
jump_label_init();
|
|
static_call_init();
|
|
early_security_init();
|
|
setup_boot_config();
|
|
setup_command_line(command_line);
|
|
setup_nr_cpu_ids();
|
|
setup_per_cpu_areas();
|
|
smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
|
|
early_numa_node_init();
|
|
boot_cpu_hotplug_init();
|
|
|
|
print_kernel_cmdline(saved_command_line);
|
|
/* parameters may set static keys */
|
|
parse_early_param();
|
|
after_dashes = parse_args("Booting kernel",
|
|
static_command_line, __start___param,
|
|
__stop___param - __start___param,
|
|
-1, -1, NULL, &unknown_bootoption);
|
|
print_unknown_bootoptions();
|
|
if (!IS_ERR_OR_NULL(after_dashes))
|
|
parse_args("Setting init args", after_dashes, NULL, 0, -1, -1,
|
|
NULL, set_init_arg);
|
|
if (extra_init_args)
|
|
parse_args("Setting extra init args", extra_init_args,
|
|
NULL, 0, -1, -1, NULL, set_init_arg);
|
|
|
|
/* Architectural and non-timekeeping rng init, before allocator init */
|
|
random_init_early(command_line);
|
|
|
|
/*
|
|
* These use large bootmem allocations and must precede
|
|
* initalization of page allocator
|
|
*/
|
|
setup_log_buf(0);
|
|
vfs_caches_init_early();
|
|
sort_main_extable();
|
|
trap_init();
|
|
mm_core_init();
|
|
maple_tree_init();
|
|
poking_init();
|
|
ftrace_init();
|
|
|
|
/* trace_printk can be enabled here */
|
|
early_trace_init();
|
|
|
|
/*
|
|
* Set up the scheduler prior starting any interrupts (such as the
|
|
* timer interrupt). Full topology setup happens at smp_init()
|
|
* time - but meanwhile we still have a functioning scheduler.
|
|
*/
|
|
sched_init();
|
|
|
|
if (WARN(!irqs_disabled(),
|
|
"Interrupts were enabled *very* early, fixing it\n"))
|
|
local_irq_disable();
|
|
radix_tree_init();
|
|
|
|
/*
|
|
* Set up housekeeping before setting up workqueues to allow the unbound
|
|
* workqueue to take non-housekeeping into account.
|
|
*/
|
|
housekeeping_init();
|
|
|
|
/*
|
|
* Allow workqueue creation and work item queueing/cancelling
|
|
* early. Work item execution depends on kthreads and starts after
|
|
* workqueue_init().
|
|
*/
|
|
workqueue_init_early();
|
|
|
|
rcu_init();
|
|
kvfree_rcu_init();
|
|
|
|
/* Trace events are available after this */
|
|
trace_init();
|
|
|
|
if (initcall_debug)
|
|
initcall_debug_enable();
|
|
|
|
context_tracking_init();
|
|
/* init some links before init_ISA_irqs() */
|
|
early_irq_init();
|
|
init_IRQ();
|
|
tick_init();
|
|
rcu_init_nohz();
|
|
timers_init();
|
|
srcu_init();
|
|
hrtimers_init();
|
|
softirq_init();
|
|
timekeeping_init();
|
|
time_init();
|
|
|
|
/* This must be after timekeeping is initialized */
|
|
random_init();
|
|
|
|
/* These make use of the fully initialized rng */
|
|
kfence_init();
|
|
boot_init_stack_canary();
|
|
|
|
perf_event_init();
|
|
profile_init();
|
|
call_function_init();
|
|
WARN(!irqs_disabled(), "Interrupts were enabled early\n");
|
|
|
|
early_boot_irqs_disabled = false;
|
|
local_irq_enable();
|
|
|
|
kmem_cache_init_late();
|
|
|
|
/*
|
|
* HACK ALERT! This is early. We're enabling the console before
|
|
* we've done PCI setups etc, and console_init() must be aware of
|
|
* this. But we do want output early, in case something goes wrong.
|
|
*/
|
|
console_init();
|
|
if (panic_later)
|
|
panic("Too many boot %s vars at `%s'", panic_later,
|
|
panic_param);
|
|
|
|
lockdep_init();
|
|
|
|
/*
|
|
* Need to run this when irqs are enabled, because it wants
|
|
* to self-test [hard/soft]-irqs on/off lock inversion bugs
|
|
* too:
|
|
*/
|
|
locking_selftest();
|
|
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
if (initrd_start && !initrd_below_start_ok &&
|
|
page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
|
|
pr_crit("initrd overwritten (0x%08lx < 0x%08lx) - disabling it.\n",
|
|
page_to_pfn(virt_to_page((void *)initrd_start)),
|
|
min_low_pfn);
|
|
initrd_start = 0;
|
|
}
|
|
#endif
|
|
setup_per_cpu_pageset();
|
|
numa_policy_init();
|
|
acpi_early_init();
|
|
if (late_time_init)
|
|
late_time_init();
|
|
sched_clock_init();
|
|
calibrate_delay();
|
|
|
|
arch_cpu_finalize_init();
|
|
|
|
pid_idr_init();
|
|
anon_vma_init();
|
|
thread_stack_cache_init();
|
|
cred_init();
|
|
fork_init();
|
|
proc_caches_init();
|
|
uts_ns_init();
|
|
time_ns_init();
|
|
key_init();
|
|
security_init();
|
|
dbg_late_init();
|
|
net_ns_init();
|
|
vfs_caches_init();
|
|
pagecache_init();
|
|
signals_init();
|
|
seq_file_init();
|
|
proc_root_init();
|
|
nsfs_init();
|
|
pidfs_init();
|
|
cpuset_init();
|
|
mem_cgroup_init();
|
|
cgroup_init();
|
|
taskstats_init_early();
|
|
delayacct_init();
|
|
|
|
acpi_subsystem_init();
|
|
arch_post_acpi_subsys_init();
|
|
kcsan_init();
|
|
|
|
/* Do the rest non-__init'ed, we're now alive */
|
|
rest_init();
|
|
|
|
/*
|
|
* Avoid stack canaries in callers of boot_init_stack_canary for gcc-10
|
|
* and older.
|
|
*/
|
|
#if !__has_attribute(__no_stack_protector__)
|
|
prevent_tail_call_optimization();
|
|
#endif
|
|
}
|
|
|
|
/* Call all constructor functions linked into the kernel. */
|
|
static void __init do_ctors(void)
|
|
{
|
|
/*
|
|
* For UML, the constructors have already been called by the
|
|
* normal setup code as it's just a normal ELF binary, so we
|
|
* cannot do it again - but we do need CONFIG_CONSTRUCTORS
|
|
* even on UML for modules.
|
|
*/
|
|
#if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML)
|
|
ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
|
|
|
|
for (; fn < (ctor_fn_t *) __ctors_end; fn++)
|
|
(*fn)();
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_KALLSYMS
|
|
struct blacklist_entry {
|
|
struct list_head next;
|
|
char *buf;
|
|
};
|
|
|
|
static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
|
|
|
|
static int __init initcall_blacklist(char *str)
|
|
{
|
|
char *str_entry;
|
|
struct blacklist_entry *entry;
|
|
|
|
/* str argument is a comma-separated list of functions */
|
|
do {
|
|
str_entry = strsep(&str, ",");
|
|
if (str_entry) {
|
|
pr_debug("blacklisting initcall %s\n", str_entry);
|
|
entry = memblock_alloc_or_panic(sizeof(*entry),
|
|
SMP_CACHE_BYTES);
|
|
entry->buf = memblock_alloc_or_panic(strlen(str_entry) + 1,
|
|
SMP_CACHE_BYTES);
|
|
strcpy(entry->buf, str_entry);
|
|
list_add(&entry->next, &blacklisted_initcalls);
|
|
}
|
|
} while (str_entry);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static bool __init_or_module initcall_blacklisted(initcall_t fn)
|
|
{
|
|
struct blacklist_entry *entry;
|
|
char fn_name[KSYM_SYMBOL_LEN];
|
|
unsigned long addr;
|
|
|
|
if (list_empty(&blacklisted_initcalls))
|
|
return false;
|
|
|
|
addr = (unsigned long) dereference_function_descriptor(fn);
|
|
sprint_symbol_no_offset(fn_name, addr);
|
|
|
|
/*
|
|
* fn will be "function_name [module_name]" where [module_name] is not
|
|
* displayed for built-in init functions. Strip off the [module_name].
|
|
*/
|
|
strreplace(fn_name, ' ', '\0');
|
|
|
|
list_for_each_entry(entry, &blacklisted_initcalls, next) {
|
|
if (!strcmp(fn_name, entry->buf)) {
|
|
pr_debug("initcall %s blacklisted\n", fn_name);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
#else
|
|
static int __init initcall_blacklist(char *str)
|
|
{
|
|
pr_warn("initcall_blacklist requires CONFIG_KALLSYMS\n");
|
|
return 0;
|
|
}
|
|
|
|
static bool __init_or_module initcall_blacklisted(initcall_t fn)
|
|
{
|
|
return false;
|
|
}
|
|
#endif
|
|
__setup("initcall_blacklist=", initcall_blacklist);
|
|
|
|
static __init_or_module void
|
|
trace_initcall_start_cb(void *data, initcall_t fn)
|
|
{
|
|
ktime_t *calltime = data;
|
|
|
|
printk(KERN_DEBUG "calling %pS @ %i\n", fn, task_pid_nr(current));
|
|
*calltime = ktime_get();
|
|
}
|
|
|
|
static __init_or_module void
|
|
trace_initcall_finish_cb(void *data, initcall_t fn, int ret)
|
|
{
|
|
ktime_t rettime, *calltime = data;
|
|
|
|
rettime = ktime_get();
|
|
printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n",
|
|
fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime));
|
|
}
|
|
|
|
static __init_or_module void
|
|
trace_initcall_level_cb(void *data, const char *level)
|
|
{
|
|
printk(KERN_DEBUG "entering initcall level: %s\n", level);
|
|
}
|
|
|
|
static ktime_t initcall_calltime;
|
|
|
|
#ifdef TRACEPOINTS_ENABLED
|
|
static void __init initcall_debug_enable(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_trace_initcall_start(trace_initcall_start_cb,
|
|
&initcall_calltime);
|
|
ret |= register_trace_initcall_finish(trace_initcall_finish_cb,
|
|
&initcall_calltime);
|
|
ret |= register_trace_initcall_level(trace_initcall_level_cb, NULL);
|
|
WARN(ret, "Failed to register initcall tracepoints\n");
|
|
}
|
|
# define do_trace_initcall_start trace_initcall_start
|
|
# define do_trace_initcall_finish trace_initcall_finish
|
|
# define do_trace_initcall_level trace_initcall_level
|
|
#else
|
|
static inline void do_trace_initcall_start(initcall_t fn)
|
|
{
|
|
if (!initcall_debug)
|
|
return;
|
|
trace_initcall_start_cb(&initcall_calltime, fn);
|
|
}
|
|
static inline void do_trace_initcall_finish(initcall_t fn, int ret)
|
|
{
|
|
if (!initcall_debug)
|
|
return;
|
|
trace_initcall_finish_cb(&initcall_calltime, fn, ret);
|
|
}
|
|
static inline void do_trace_initcall_level(const char *level)
|
|
{
|
|
if (!initcall_debug)
|
|
return;
|
|
trace_initcall_level_cb(NULL, level);
|
|
}
|
|
#endif /* !TRACEPOINTS_ENABLED */
|
|
|
|
int __init_or_module do_one_initcall(initcall_t fn)
|
|
{
|
|
int count = preempt_count();
|
|
char msgbuf[64];
|
|
int ret;
|
|
|
|
if (initcall_blacklisted(fn))
|
|
return -EPERM;
|
|
|
|
do_trace_initcall_start(fn);
|
|
ret = fn();
|
|
do_trace_initcall_finish(fn, ret);
|
|
|
|
msgbuf[0] = 0;
|
|
|
|
if (preempt_count() != count) {
|
|
sprintf(msgbuf, "preemption imbalance ");
|
|
preempt_count_set(count);
|
|
}
|
|
if (irqs_disabled()) {
|
|
strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
|
|
local_irq_enable();
|
|
}
|
|
WARN(msgbuf[0], "initcall %pS returned with %s\n", fn, msgbuf);
|
|
|
|
add_latent_entropy();
|
|
return ret;
|
|
}
|
|
|
|
|
|
static initcall_entry_t *initcall_levels[] __initdata = {
|
|
__initcall0_start,
|
|
__initcall1_start,
|
|
__initcall2_start,
|
|
__initcall3_start,
|
|
__initcall4_start,
|
|
__initcall5_start,
|
|
__initcall6_start,
|
|
__initcall7_start,
|
|
__initcall_end,
|
|
};
|
|
|
|
/* Keep these in sync with initcalls in include/linux/init.h */
|
|
static const char *initcall_level_names[] __initdata = {
|
|
"pure",
|
|
"core",
|
|
"postcore",
|
|
"arch",
|
|
"subsys",
|
|
"fs",
|
|
"device",
|
|
"late",
|
|
};
|
|
|
|
static int __init ignore_unknown_bootoption(char *param, char *val,
|
|
const char *unused, void *arg)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void __init do_initcall_level(int level, char *command_line)
|
|
{
|
|
initcall_entry_t *fn;
|
|
|
|
parse_args(initcall_level_names[level],
|
|
command_line, __start___param,
|
|
__stop___param - __start___param,
|
|
level, level,
|
|
NULL, ignore_unknown_bootoption);
|
|
|
|
do_trace_initcall_level(initcall_level_names[level]);
|
|
for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
|
|
do_one_initcall(initcall_from_entry(fn));
|
|
}
|
|
|
|
static void __init do_initcalls(void)
|
|
{
|
|
int level;
|
|
size_t len = saved_command_line_len + 1;
|
|
char *command_line;
|
|
|
|
command_line = kzalloc(len, GFP_KERNEL);
|
|
if (!command_line)
|
|
panic("%s: Failed to allocate %zu bytes\n", __func__, len);
|
|
|
|
for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
|
|
/* Parser modifies command_line, restore it each time */
|
|
strcpy(command_line, saved_command_line);
|
|
do_initcall_level(level, command_line);
|
|
}
|
|
|
|
kfree(command_line);
|
|
}
|
|
|
|
/*
|
|
* Ok, the machine is now initialized. None of the devices
|
|
* have been touched yet, but the CPU subsystem is up and
|
|
* running, and memory and process management works.
|
|
*
|
|
* Now we can finally start doing some real work..
|
|
*/
|
|
static void __init do_basic_setup(void)
|
|
{
|
|
cpuset_init_smp();
|
|
driver_init();
|
|
init_irq_proc();
|
|
do_ctors();
|
|
do_initcalls();
|
|
}
|
|
|
|
static void __init do_pre_smp_initcalls(void)
|
|
{
|
|
initcall_entry_t *fn;
|
|
|
|
do_trace_initcall_level("early");
|
|
for (fn = __initcall_start; fn < __initcall0_start; fn++)
|
|
do_one_initcall(initcall_from_entry(fn));
|
|
}
|
|
|
|
static int run_init_process(const char *init_filename)
|
|
{
|
|
const char *const *p;
|
|
|
|
argv_init[0] = init_filename;
|
|
pr_info("Run %s as init process\n", init_filename);
|
|
pr_debug(" with arguments:\n");
|
|
for (p = argv_init; *p; p++)
|
|
pr_debug(" %s\n", *p);
|
|
pr_debug(" with environment:\n");
|
|
for (p = envp_init; *p; p++)
|
|
pr_debug(" %s\n", *p);
|
|
return kernel_execve(init_filename, argv_init, envp_init);
|
|
}
|
|
|
|
static int try_to_run_init_process(const char *init_filename)
|
|
{
|
|
int ret;
|
|
|
|
ret = run_init_process(init_filename);
|
|
|
|
if (ret && ret != -ENOENT) {
|
|
pr_err("Starting init: %s exists but couldn't execute it (error %d)\n",
|
|
init_filename, ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static noinline void __init kernel_init_freeable(void);
|
|
|
|
#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
|
|
bool rodata_enabled __ro_after_init = true;
|
|
|
|
#ifndef arch_parse_debug_rodata
|
|
static inline bool arch_parse_debug_rodata(char *str) { return false; }
|
|
#endif
|
|
|
|
static int __init set_debug_rodata(char *str)
|
|
{
|
|
if (arch_parse_debug_rodata(str))
|
|
return 0;
|
|
|
|
if (str && !strcmp(str, "on"))
|
|
rodata_enabled = true;
|
|
else if (str && !strcmp(str, "off"))
|
|
rodata_enabled = false;
|
|
else
|
|
pr_warn("Invalid option string for rodata: '%s'\n", str);
|
|
return 0;
|
|
}
|
|
early_param("rodata", set_debug_rodata);
|
|
#endif
|
|
|
|
static void mark_readonly(void)
|
|
{
|
|
if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && rodata_enabled) {
|
|
/*
|
|
* load_module() results in W+X mappings, which are cleaned
|
|
* up with init_free_wq. Let's make sure that queued work is
|
|
* flushed so that we don't hit false positives looking for
|
|
* insecure pages which are W+X.
|
|
*/
|
|
flush_module_init_free_work();
|
|
jump_label_init_ro();
|
|
mark_rodata_ro();
|
|
debug_checkwx();
|
|
rodata_test();
|
|
} else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
|
|
pr_info("Kernel memory protection disabled.\n");
|
|
} else if (IS_ENABLED(CONFIG_ARCH_HAS_STRICT_KERNEL_RWX)) {
|
|
pr_warn("Kernel memory protection not selected by kernel config.\n");
|
|
} else {
|
|
pr_warn("This architecture does not have kernel memory protection.\n");
|
|
}
|
|
}
|
|
|
|
void __weak free_initmem(void)
|
|
{
|
|
free_initmem_default(POISON_FREE_INITMEM);
|
|
}
|
|
|
|
static int __ref kernel_init(void *unused)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* Wait until kthreadd is all set-up.
|
|
*/
|
|
wait_for_completion(&kthreadd_done);
|
|
|
|
kernel_init_freeable();
|
|
/* need to finish all async __init code before freeing the memory */
|
|
async_synchronize_full();
|
|
|
|
system_state = SYSTEM_FREEING_INITMEM;
|
|
kprobe_free_init_mem();
|
|
ftrace_free_init_mem();
|
|
kgdb_free_init_mem();
|
|
exit_boot_config();
|
|
free_initmem();
|
|
mark_readonly();
|
|
|
|
/*
|
|
* Kernel mappings are now finalized - update the userspace page-table
|
|
* to finalize PTI.
|
|
*/
|
|
pti_finalize();
|
|
|
|
system_state = SYSTEM_RUNNING;
|
|
numa_default_policy();
|
|
|
|
rcu_end_inkernel_boot();
|
|
|
|
do_sysctl_args();
|
|
|
|
if (ramdisk_execute_command) {
|
|
ret = run_init_process(ramdisk_execute_command);
|
|
if (!ret)
|
|
return 0;
|
|
pr_err("Failed to execute %s (error %d)\n",
|
|
ramdisk_execute_command, ret);
|
|
}
|
|
|
|
/*
|
|
* We try each of these until one succeeds.
|
|
*
|
|
* The Bourne shell can be used instead of init if we are
|
|
* trying to recover a really broken machine.
|
|
*/
|
|
if (execute_command) {
|
|
ret = run_init_process(execute_command);
|
|
if (!ret)
|
|
return 0;
|
|
panic("Requested init %s failed (error %d).",
|
|
execute_command, ret);
|
|
}
|
|
|
|
if (CONFIG_DEFAULT_INIT[0] != '\0') {
|
|
ret = run_init_process(CONFIG_DEFAULT_INIT);
|
|
if (ret)
|
|
pr_err("Default init %s failed (error %d)\n",
|
|
CONFIG_DEFAULT_INIT, ret);
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
if (!try_to_run_init_process("/sbin/init") ||
|
|
!try_to_run_init_process("/etc/init") ||
|
|
!try_to_run_init_process("/bin/init") ||
|
|
!try_to_run_init_process("/bin/sh"))
|
|
return 0;
|
|
|
|
panic("No working init found. Try passing init= option to kernel. "
|
|
"See Linux Documentation/admin-guide/init.rst for guidance.");
|
|
}
|
|
|
|
/* Open /dev/console, for stdin/stdout/stderr, this should never fail */
|
|
void __init console_on_rootfs(void)
|
|
{
|
|
struct file *file = filp_open("/dev/console", O_RDWR, 0);
|
|
|
|
if (IS_ERR(file)) {
|
|
pr_err("Warning: unable to open an initial console.\n");
|
|
return;
|
|
}
|
|
init_dup(file);
|
|
init_dup(file);
|
|
init_dup(file);
|
|
fput(file);
|
|
}
|
|
|
|
static noinline void __init kernel_init_freeable(void)
|
|
{
|
|
/* Now the scheduler is fully set up and can do blocking allocations */
|
|
gfp_allowed_mask = __GFP_BITS_MASK;
|
|
|
|
/*
|
|
* init can allocate pages on any node
|
|
*/
|
|
set_mems_allowed(node_states[N_MEMORY]);
|
|
|
|
cad_pid = get_pid(task_pid(current));
|
|
|
|
smp_prepare_cpus(setup_max_cpus);
|
|
|
|
workqueue_init();
|
|
|
|
init_mm_internals();
|
|
|
|
do_pre_smp_initcalls();
|
|
lockup_detector_init();
|
|
|
|
smp_init();
|
|
sched_init_smp();
|
|
|
|
workqueue_init_topology();
|
|
async_init();
|
|
padata_init();
|
|
page_alloc_init_late();
|
|
|
|
do_basic_setup();
|
|
|
|
kunit_run_all_tests();
|
|
|
|
wait_for_initramfs();
|
|
console_on_rootfs();
|
|
|
|
/*
|
|
* check if there is an early userspace init. If yes, let it do all
|
|
* the work
|
|
*/
|
|
int ramdisk_command_access;
|
|
ramdisk_command_access = init_eaccess(ramdisk_execute_command);
|
|
if (ramdisk_command_access != 0) {
|
|
pr_warn("check access for rdinit=%s failed: %i, ignoring\n",
|
|
ramdisk_execute_command, ramdisk_command_access);
|
|
ramdisk_execute_command = NULL;
|
|
prepare_namespace();
|
|
}
|
|
|
|
/*
|
|
* Ok, we have completed the initial bootup, and
|
|
* we're essentially up and running. Get rid of the
|
|
* initmem segments and start the user-mode stuff..
|
|
*
|
|
* rootfs is available now, try loading the public keys
|
|
* and default modules
|
|
*/
|
|
|
|
integrity_load_keys();
|
|
}
|