linux/arch/mn10300/kernel/setup.c
Akira Takeuchi e3f12a5304 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: <level>_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 <dhowells@redhat.com>
2013-06-28 16:53:03 +01:00

287 lines
6.7 KiB
C

/* MN10300 Arch-specific initialisation
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/seq_file.h>
#include <linux/cpu.h>
#include <asm/processor.h>
#include <linux/console.h>
#include <asm/uaccess.h>
#include <asm/setup.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <proc/proc.h>
#include <asm/fpu.h>
#include <asm/sections.h>
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";
char __initdata redboot_platform_name[COMMAND_LINE_SIZE];
static struct resource code_resource = {
.start = 0x100000,
.end = 0,
.name = "Kernel code",
};
static struct resource data_resource = {
.start = 0,
.end = 0,
.name = "Kernel data",
};
static unsigned long __initdata phys_memory_base;
static unsigned long __initdata phys_memory_end;
static unsigned long __initdata memory_end;
unsigned long memory_size;
struct thread_info *__current_ti = &init_thread_union.thread_info;
struct task_struct *__current = &init_task;
#define mn10300_known_cpus 5
static const char *const mn10300_cputypes[] = {
"am33-1",
"am33-2",
"am34-1",
"am33-3",
"am34-2",
"unknown"
};
/*
* Pick out the memory size. We look for mem=size,
* where size is "size[KkMm]"
*/
static int __init early_mem(char *p)
{
memory_size = memparse(p, &p);
if (memory_size == 0)
panic("Memory size not known\n");
return 0;
}
early_param("mem", early_mem);
/*
* architecture specific setup
*/
void __init setup_arch(char **cmdline_p)
{
unsigned long bootmap_size;
unsigned long kstart_pfn, start_pfn, free_pfn, end_pfn;
cpu_init();
unit_setup();
smp_init_cpus();
/* 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;
init_mm.end_data = (unsigned long) &_edata;
init_mm.brk = (unsigned long) &_end;
code_resource.start = virt_to_bus(&_text);
code_resource.end = virt_to_bus(&_etext)-1;
data_resource.start = virt_to_bus(&_etext);
data_resource.end = virt_to_bus(&_edata)-1;
start_pfn = (CONFIG_KERNEL_RAM_BASE_ADDRESS >> PAGE_SHIFT);
kstart_pfn = PFN_UP(__pa(&_text));
free_pfn = PFN_UP(__pa(&_end));
end_pfn = PFN_DOWN(__pa(memory_end));
bootmap_size = init_bootmem_node(&contig_page_data,
free_pfn,
start_pfn,
end_pfn);
if (kstart_pfn > start_pfn)
free_bootmem(PFN_PHYS(start_pfn),
PFN_PHYS(kstart_pfn - start_pfn));
free_bootmem(PFN_PHYS(free_pfn),
PFN_PHYS(end_pfn - free_pfn));
/* If interrupt vector table is in main ram, then we need to
reserve the page it is occupying. */
if (CONFIG_INTERRUPT_VECTOR_BASE >= CONFIG_KERNEL_RAM_BASE_ADDRESS &&
CONFIG_INTERRUPT_VECTOR_BASE < memory_end)
reserve_bootmem(CONFIG_INTERRUPT_VECTOR_BASE, PAGE_SIZE,
BOOTMEM_DEFAULT);
reserve_bootmem(PAGE_ALIGN(PFN_PHYS(free_pfn)), bootmap_size,
BOOTMEM_DEFAULT);
#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
conswitchp = &dummy_con;
#endif
#endif
paging_init();
}
/*
* perform CPU initialisation
*/
void __init cpu_init(void)
{
unsigned long cpurev = CPUREV, type;
type = (CPUREV & CPUREV_TYPE) >> CPUREV_TYPE_S;
if (type > mn10300_known_cpus)
type = mn10300_known_cpus;
printk(KERN_INFO "Panasonic %s, rev %ld\n",
mn10300_cputypes[type],
(cpurev & CPUREV_REVISION) >> CPUREV_REVISION_S);
get_mem_info(&phys_memory_base, &memory_size);
phys_memory_end = phys_memory_base + memory_size;
fpu_init_state();
}
static struct cpu cpu_devices[NR_CPUS];
static int __init topology_init(void)
{
int i;
for_each_present_cpu(i)
register_cpu(&cpu_devices[i], i);
return 0;
}
subsys_initcall(topology_init);
/*
* Get CPU information for use by the procfs.
*/
static int show_cpuinfo(struct seq_file *m, void *v)
{
#ifdef CONFIG_SMP
struct mn10300_cpuinfo *c = v;
unsigned long cpu_id = c - cpu_data;
unsigned long cpurev = c->type, type, icachesz, dcachesz;
#else /* CONFIG_SMP */
unsigned long cpu_id = 0;
unsigned long cpurev = CPUREV, type, icachesz, dcachesz;
#endif /* CONFIG_SMP */
#ifdef CONFIG_SMP
if (!cpu_online(cpu_id))
return 0;
#endif
type = (cpurev & CPUREV_TYPE) >> CPUREV_TYPE_S;
if (type > mn10300_known_cpus)
type = mn10300_known_cpus;
icachesz =
((cpurev & CPUREV_ICWAY ) >> CPUREV_ICWAY_S) *
((cpurev & CPUREV_ICSIZE) >> CPUREV_ICSIZE_S) *
1024;
dcachesz =
((cpurev & CPUREV_DCWAY ) >> CPUREV_DCWAY_S) *
((cpurev & CPUREV_DCSIZE) >> CPUREV_DCSIZE_S) *
1024;
seq_printf(m,
"processor : %ld\n"
"vendor_id : " PROCESSOR_VENDOR_NAME "\n"
"cpu core : %s\n"
"cpu rev : %lu\n"
"model name : " PROCESSOR_MODEL_NAME "\n"
"icache size: %lu\n"
"dcache size: %lu\n",
cpu_id,
mn10300_cputypes[type],
(cpurev & CPUREV_REVISION) >> CPUREV_REVISION_S,
icachesz,
dcachesz
);
seq_printf(m,
"ioclk speed: %lu.%02luMHz\n"
"bogomips : %lu.%02lu\n\n",
MN10300_IOCLK / 1000000,
(MN10300_IOCLK / 10000) % 100,
#ifdef CONFIG_SMP
c->loops_per_jiffy / (500000 / HZ),
(c->loops_per_jiffy / (5000 / HZ)) % 100
#else /* CONFIG_SMP */
loops_per_jiffy / (500000 / HZ),
(loops_per_jiffy / (5000 / HZ)) % 100
#endif /* CONFIG_SMP */
);
return 0;
}
static void *c_start(struct seq_file *m, loff_t *pos)
{
return *pos < NR_CPUS ? cpu_data + *pos : NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return c_start(m, pos);
}
static void c_stop(struct seq_file *m, void *v)
{
}
const struct seq_operations cpuinfo_op = {
.start = c_start,
.next = c_next,
.stop = c_stop,
.show = show_cpuinfo,
};