1 From: Yousong Zhou <yszhou4tech@gmail.com>
2 Subject: MIPS: kexec: Accept command line parameters from userspace.
4 Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
6 arch/mips/kernel/machine_kexec.c | 153 +++++++++++++++++++++++++++++++-----
7 arch/mips/kernel/machine_kexec.h | 20 +++++
8 arch/mips/kernel/relocate_kernel.S | 21 +++--
9 3 files changed, 167 insertions(+), 27 deletions(-)
10 create mode 100644 arch/mips/kernel/machine_kexec.h
12 --- a/arch/mips/kernel/machine_kexec.c
13 +++ b/arch/mips/kernel/machine_kexec.c
16 #include <linux/delay.h>
18 +#include <asm/bootinfo.h>
19 #include <asm/cacheflush.h>
22 -extern const unsigned char relocate_new_kernel[];
23 -extern const size_t relocate_new_kernel_size;
25 -extern unsigned long kexec_start_address;
26 -extern unsigned long kexec_indirection_page;
27 +#include <asm/uaccess.h>
28 +#include "machine_kexec.h"
30 int (*_machine_kexec_prepare)(struct kimage *) = NULL;
31 void (*_machine_kexec_shutdown)(void) = NULL;
32 @@ -28,9 +25,117 @@ atomic_t kexec_ready_to_reboot = ATOMIC_
33 void (*_crash_smp_send_stop)(void) = NULL;
36 +static void machine_kexec_print_args(void)
38 + unsigned long argc = (int)kexec_args[0];
41 + pr_info("kexec_args[0] (argc): %lu\n", argc);
42 + pr_info("kexec_args[1] (argv): %p\n", (void *)kexec_args[1]);
43 + pr_info("kexec_args[2] (env ): %p\n", (void *)kexec_args[2]);
44 + pr_info("kexec_args[3] (desc): %p\n", (void *)kexec_args[3]);
46 + for (i = 0; i < argc; i++) {
47 + pr_info("kexec_argv[%d] = %p, %s\n",
48 + i, kexec_argv[i], kexec_argv[i]);
52 +static void machine_kexec_init_argv(struct kimage *image)
54 + void __user *buf = NULL;
60 + for (i = 0; i < image->nr_segments; i++) {
61 + struct kexec_segment *seg;
63 + seg = &image->segment[i];
67 + if (strncmp((char *) seg->buf, "kexec ", 6))
78 + size = KEXEC_COMMAND_LINE_SIZE;
79 + size = min(size, bufsz);
81 + pr_warn("kexec command line truncated to %zd bytes\n", size);
83 + /* Copy to kernel space */
84 + if (copy_from_user(kexec_argv_buf, buf, size))
85 + pr_warn("kexec command line copy to kernel space failed\n");
87 + kexec_argv_buf[size - 1] = 0;
90 +static void machine_kexec_parse_argv(struct kimage *image)
92 + char *reboot_code_buffer;
98 + ptr = kexec_argv_buf;
102 + * convert command line string to array of parameters
103 + * (as bootloader does).
105 + while (ptr && *ptr && (KEXEC_MAX_ARGC > argc)) {
111 + kexec_argv[argc++] = ptr;
112 + ptr = strchr(ptr, ' ');
118 + kexec_args[0] = argc;
119 + kexec_args[1] = (unsigned long)kexec_argv;
123 + reboot_code_buffer = page_address(image->control_code_page);
124 + reloc_delta = reboot_code_buffer - (char *)kexec_relocate_new_kernel;
126 + kexec_args[1] += reloc_delta;
127 + for (i = 0; i < argc; i++)
128 + kexec_argv[i] += reloc_delta;
132 machine_kexec_prepare(struct kimage *kimage)
135 + * Whenever arguments passed from kexec-tools, Init the arguments as
136 + * the original ones to try avoiding booting failure.
139 + kexec_args[0] = fw_arg0;
140 + kexec_args[1] = fw_arg1;
141 + kexec_args[2] = fw_arg2;
142 + kexec_args[3] = fw_arg3;
144 + machine_kexec_init_argv(kimage);
145 + machine_kexec_parse_argv(kimage);
147 if (_machine_kexec_prepare)
148 return _machine_kexec_prepare(kimage);
150 @@ -67,10 +172,12 @@ machine_kexec(struct kimage *image)
154 - (unsigned long)page_address(image->control_code_page);
155 + (unsigned long)page_address(image->control_code_page);
156 + pr_info("reboot_code_buffer = %p\n", (void *)reboot_code_buffer);
158 kexec_start_address =
159 (unsigned long) phys_to_virt(image->start);
160 + pr_info("kexec_start_address = %p\n", (void *)kexec_start_address);
162 if (image->type == KEXEC_TYPE_DEFAULT) {
163 kexec_indirection_page =
164 @@ -78,9 +185,19 @@ machine_kexec(struct kimage *image)
166 kexec_indirection_page = (unsigned long)&image->head;
168 + pr_info("kexec_indirection_page = %p\n", (void *)kexec_indirection_page);
170 - memcpy((void*)reboot_code_buffer, relocate_new_kernel,
171 - relocate_new_kernel_size);
172 + pr_info("Where is memcpy: %p\n", memcpy);
173 + pr_info("kexec_relocate_new_kernel = %p, kexec_relocate_new_kernel_end = %p\n",
174 + (void *)kexec_relocate_new_kernel, &kexec_relocate_new_kernel_end);
175 + pr_info("Copy %lu bytes from %p to %p\n", KEXEC_RELOCATE_NEW_KERNEL_SIZE,
176 + (void *)kexec_relocate_new_kernel, (void *)reboot_code_buffer);
177 + memcpy((void*)reboot_code_buffer, kexec_relocate_new_kernel,
178 + KEXEC_RELOCATE_NEW_KERNEL_SIZE);
180 + pr_info("Before _print_args().\n");
181 + machine_kexec_print_args();
182 + pr_info("Before eval loop.\n");
185 * The generic kexec code builds a page list with physical
186 @@ -102,15 +219,16 @@ machine_kexec(struct kimage *image)
188 * we do not want to be bothered.
190 + pr_info("Before irq_disable.\n");
193 - printk("Will call new kernel at %08lx\n", image->start);
194 - printk("Bye ...\n");
195 + pr_info("Will call new kernel at %08lx\n", image->start);
196 + pr_info("Bye ...\n");
199 /* All secondary cpus now may jump to kexec_wait cycle */
200 relocated_kexec_smp_wait = reboot_code_buffer +
201 - (void *)(kexec_smp_wait - relocate_new_kernel);
202 + (void *)(kexec_smp_wait - kexec_relocate_new_kernel);
204 atomic_set(&kexec_ready_to_reboot, 1);
207 +++ b/arch/mips/kernel/machine_kexec.h
209 +#ifndef _MACHINE_KEXEC_H
210 +#define _MACHINE_KEXEC_H
212 +#ifndef __ASSEMBLY__
213 +extern const unsigned char kexec_relocate_new_kernel[];
214 +extern unsigned long kexec_relocate_new_kernel_end;
215 +extern unsigned long kexec_start_address;
216 +extern unsigned long kexec_indirection_page;
218 +extern char kexec_argv_buf[];
219 +extern char *kexec_argv[];
221 +#define KEXEC_RELOCATE_NEW_KERNEL_SIZE ((unsigned long)&kexec_relocate_new_kernel_end - (unsigned long)kexec_relocate_new_kernel)
222 +#endif /* !__ASSEMBLY__ */
224 +#define KEXEC_COMMAND_LINE_SIZE 256
225 +#define KEXEC_ARGV_SIZE (KEXEC_COMMAND_LINE_SIZE / 16)
226 +#define KEXEC_MAX_ARGC (KEXEC_ARGV_SIZE / sizeof(long))
229 --- a/arch/mips/kernel/relocate_kernel.S
230 +++ b/arch/mips/kernel/relocate_kernel.S
232 #include <asm/mipsregs.h>
233 #include <asm/stackframe.h>
234 #include <asm/addrspace.h>
235 +#include "machine_kexec.h"
237 -LEAF(relocate_new_kernel)
238 +LEAF(kexec_relocate_new_kernel)
242 @@ -98,7 +99,7 @@ done:
244 /* jump to kexec_start_address */
246 - END(relocate_new_kernel)
247 + END(kexec_relocate_new_kernel)
251 @@ -184,9 +185,15 @@ kexec_indirection_page:
253 .size kexec_indirection_page, PTRSIZE
255 -relocate_new_kernel_end:
257 + EXPORT(kexec_argv_buf)
258 + .skip KEXEC_COMMAND_LINE_SIZE
259 + .size kexec_argv_buf, KEXEC_COMMAND_LINE_SIZE
263 + .skip KEXEC_ARGV_SIZE
264 + .size kexec_argv, KEXEC_ARGV_SIZE
266 -relocate_new_kernel_size:
267 - EXPORT(relocate_new_kernel_size)
268 - PTR relocate_new_kernel_end - relocate_new_kernel
269 - .size relocate_new_kernel_size, PTRSIZE
270 +kexec_relocate_new_kernel_end:
271 + EXPORT(kexec_relocate_new_kernel_end)