korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-11 12:28:41 +08:00
Code Issues Packages Projects Releases Wiki Activity

bootconfig: Load boot config from the tail of initrd

Browse Source 
Load the extended boot config data from the tail of initrd
image. If there is an SKC data there, it has
[(u32)size][(u32)checksum] header (in really, this is a
footer) at the end of initrd. If the checksum (simple sum
of bytes) is match, this starts parsing it from there.

Link: http://lkml.kernel.org/r/157867222435.17873.9936667353335606867.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Masami Hiramatsu 2020-01-11 01:03:44 +09:00 committed by Steven Rostedt (VMware)
parent 76db5a27a8
commit 7684b8582c
2 changed files with 55 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
init/Kconfig
View File

@ -1217,6 +1217,7 @@ endif
config BOOT_CONFIG
bool "Boot config support"
depends on BLK_DEV_INITRD
select LIBXBC
default y
help

54
init/main.c
View File

@ -28,6 +28,7 @@
#include <linux/initrd.h>
#include <linux/memblock.h>
#include <linux/acpi.h>
#include <linux/bootconfig.h>
#include <linux/console.h>
#include <linux/nmi.h>
#include <linux/percpu.h>
@ -245,6 +246,58 @@ static int __init loglevel(char *str)
early_param("loglevel", loglevel);
#ifdef CONFIG_BOOT_CONFIG
u32 boot_config_checksum(unsigned char *p, u32 size)
{
u32 ret = 0;
while (size--)
ret += *p++;
return ret;
}
static void __init setup_boot_config(void)
{
u32 size, csum;
char *data, *copy;
u32 *hdr;
if (!initrd_end)
return;
hdr = (u32 *)(initrd_end - 8);
size = hdr[0];
csum = hdr[1];
if (size >= XBC_DATA_MAX)
return;
data = ((void *)hdr) - size;
if ((unsigned long)data < initrd_start)
return;
if (boot_config_checksum((unsigned char *)data, size) != csum)
return;
copy = memblock_alloc(size + 1, SMP_CACHE_BYTES);
if (!copy) {
pr_err("Failed to allocate memory for boot config\n");
return;
}
memcpy(copy, data, size);
copy[size] = '\0';
if (xbc_init(copy) < 0)
pr_err("Failed to parse boot config\n");
else
pr_info("Load boot config: %d bytes\n", size);
}
#else
#define setup_boot_config() do { } while (0)
#endif
/* Change NUL term back to "=", to make "param" the whole string. */
static int __init repair_env_string(char *param, char *val,
const char *unused, void *arg)
@ -595,6 +648,7 @@ asmlinkage __visible void __init start_kernel(void)
pr_notice("%s", linux_banner);
early_security_init();
setup_arch(&command_line);
setup_boot_config();
setup_command_line(command_line);
setup_nr_cpu_ids();
setup_per_cpu_areas();