From 1319916209ce8f55a4f4f848e74500633e24bb99 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Sat, 11 Jan 2020 01:04:55 +0900 Subject: [PATCH] bootconfig: init: Allow admin to use bootconfig for init command line Since the current kernel command line is too short to describe long and many options for init (e.g. systemd command line options), this allows admin to use boot config for init command line. All init command line under "init." keywords will be passed to init. For example, init.systemd { unified_cgroup_hierarchy = 1 debug_shell default_timeout_start_sec = 60 } Link: http://lkml.kernel.org/r/157867229521.17873.654222294326542349.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- init/main.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/init/main.c b/init/main.c index c0017d9d16e7..dd7da62d99a5 100644 --- a/init/main.c +++ b/init/main.c @@ -139,6 +139,8 @@ char *saved_command_line; static char *static_command_line; /* Untouched extra command line */ static char *extra_command_line; +/* Extra init arguments */ +static char *extra_init_args; static char *execute_command; static char *ramdisk_execute_command; @@ -372,6 +374,8 @@ static void __init setup_boot_config(void) pr_info("Load boot config: %d bytes\n", size); /* 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"); } } #else @@ -507,16 +511,18 @@ static inline void smp_prepare_cpus(unsigned int maxcpus) { } */ static void __init setup_command_line(char *command_line) { - size_t len, xlen = 0; + size_t len, xlen = 0, ilen = 0; if (extra_command_line) xlen = strlen(extra_command_line); + if (extra_init_args) + ilen = strlen(extra_init_args) + 4; /* for " -- " */ len = xlen + strlen(boot_command_line) + 1; - saved_command_line = memblock_alloc(len, SMP_CACHE_BYTES); + saved_command_line = memblock_alloc(len + ilen, SMP_CACHE_BYTES); if (!saved_command_line) - panic("%s: Failed to allocate %zu bytes\n", __func__, len); + panic("%s: Failed to allocate %zu bytes\n", __func__, len + ilen); static_command_line = memblock_alloc(len, SMP_CACHE_BYTES); if (!static_command_line) @@ -533,6 +539,22 @@ static void __init setup_command_line(char *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. + */ + len = strlen(saved_command_line); + if (!strstr(boot_command_line, " -- ")) { + strcpy(saved_command_line + len, " -- "); + len += 4; + } else + saved_command_line[len++] = ' '; + + strcpy(saved_command_line + len, extra_init_args); + } } /* @@ -759,6 +781,9 @@ asmlinkage __visible void __init start_kernel(void) 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); /* * These use large bootmem allocations and must precede