From e3f12a53042e26202993baa3ad4ff8768173653d Mon Sep 17 00:00:00 2001 From: Akira Takeuchi Date: Fri, 28 Jun 2013 16:53:03 +0100 Subject: mn10300: Use early_param() to parse "mem=" parameter This fixes the problem that "init=" options may not be passed to kernel correctly. parse_mem_cmdline() of mn10300 arch gets rid of "mem=" string from redboot_command_line. Then init_setup() parses the "init=" options from static_command_line, which is a copy of redboot_command_line, and keeps the pointer to the init options in execute_command variable. Since the commit 026cee0 upstream (params: _initcall-like kernel parameters), static_command_line becomes overwritten by saved_command_line at do_initcall_level(). Notice that saved_command_line is a command line which includes "mem=" string. As a result, execute_command may point to weird string by the length of "mem=" parameter. I noticed this problem when using the command line like this: mem=128M console=ttyS0,115200 init=/bin/sh Here is the processing flow of command line parameters. start_kernel() setup_arch(&command_line) parse_mem_cmdline(cmdline_p) * strcpy(boot_command_line, redboot_command_line); * Remove "mem=xxx" from redboot_command_line. * *cmdline_p = redboot_command_line; setup_command_line(command_line) <-- command_line is redboot_command_line * strcpy(saved_command_line, boot_command_line) * strcpy(static_command_line, command_line) parse_early_param() strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); parse_early_options(tmp_cmdline); parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param); parse_args("Booting ..", static_command_line, ...); init_setup() <-- save the pointer in execute_command rest_init() kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND); At this point, execute_command points to "/bin/sh" string. kernel_init() kernel_init_freeable() do_basic_setup() do_initcalls() do_initcall_level() (*) strcpy(static_command_line, saved_command_line); Here, execute_command gets to point to "200" string !! Signed-off-by: David Howells --- arch/mn10300/kernel/setup.c | 54 ++++++++++++++++++--------------------------- 1 file changed, 21 insertions(+), 33 deletions(-) (limited to 'arch/mn10300/kernel/setup.c') diff --git a/arch/mn10300/kernel/setup.c b/arch/mn10300/kernel/setup.c index 33c3bd1e5c6d..ebac9c11f796 100644 --- a/arch/mn10300/kernel/setup.c +++ b/arch/mn10300/kernel/setup.c @@ -38,6 +38,7 @@ struct mn10300_cpuinfo boot_cpu_data; /* For PCI or other memory-mapped resources */ unsigned long pci_mem_start = 0x18000000; +static char __initdata cmd_line[COMMAND_LINE_SIZE]; char redboot_command_line[COMMAND_LINE_SIZE] = "console=ttyS0,115200 root=/dev/mtdblock3 rw"; @@ -74,45 +75,19 @@ static const char *const mn10300_cputypes[] = { }; /* - * + * Pick out the memory size. We look for mem=size, + * where size is "size[KkMm]" */ -static void __init parse_mem_cmdline(char **cmdline_p) +static int __init early_mem(char *p) { - char *from, *to, c; - - /* save unparsed command line copy for /proc/cmdline */ - strcpy(boot_command_line, redboot_command_line); - - /* see if there's an explicit memory size option */ - from = redboot_command_line; - to = redboot_command_line; - c = ' '; - - for (;;) { - if (c == ' ' && !memcmp(from, "mem=", 4)) { - if (to != redboot_command_line) - to--; - memory_size = memparse(from + 4, &from); - } - - c = *(from++); - if (!c) - break; - - *(to++) = c; - } - - *to = '\0'; - *cmdline_p = redboot_command_line; + memory_size = memparse(p, &p); if (memory_size == 0) panic("Memory size not known\n"); - memory_end = (unsigned long) CONFIG_KERNEL_RAM_BASE_ADDRESS + - memory_size; - if (memory_end > phys_memory_end) - memory_end = phys_memory_end; + return 0; } +early_param("mem", early_mem); /* * architecture specific setup @@ -125,7 +100,20 @@ void __init setup_arch(char **cmdline_p) cpu_init(); unit_setup(); smp_init_cpus(); - parse_mem_cmdline(cmdline_p); + + /* save unparsed command line copy for /proc/cmdline */ + strlcpy(boot_command_line, redboot_command_line, COMMAND_LINE_SIZE); + + /* populate cmd_line too for later use, preserving boot_command_line */ + strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE); + *cmdline_p = cmd_line; + + parse_early_param(); + + memory_end = (unsigned long) CONFIG_KERNEL_RAM_BASE_ADDRESS + + memory_size; + if (memory_end > phys_memory_end) + memory_end = phys_memory_end; init_mm.start_code = (unsigned long)&_text; init_mm.end_code = (unsigned long) &_etext; -- cgit v1.2.3