2 * Firmware Assisted dump: A robust mechanism to get reliable kernel crash
3 * dump with assistance from firmware. This approach does not use kexec,
4 * instead firmware assists in booting the kdump kernel while preserving
5 * memory contents. The most of the code implementation has been adapted
6 * from phyp assisted dump implementation written by Linas Vepstas and
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 * Copyright 2011 IBM Corporation
24 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
28 #define pr_fmt(fmt) "fadump: " fmt
30 #include <linux/string.h>
31 #include <linux/memblock.h>
32 #include <linux/delay.h>
33 #include <linux/seq_file.h>
34 #include <linux/crash_dump.h>
35 #include <linux/kobject.h>
36 #include <linux/sysfs.h>
38 #include <asm/debugfs.h>
42 #include <asm/fadump.h>
43 #include <asm/setup.h>
45 static struct fw_dump fw_dump
;
46 static struct fadump_mem_struct fdm
;
47 static const struct fadump_mem_struct
*fdm_active
;
49 static DEFINE_MUTEX(fadump_mutex
);
50 struct fad_crash_memory_ranges
*crash_memory_ranges
;
51 int crash_memory_ranges_size
;
53 int max_crash_mem_ranges
;
55 /* Scan the Firmware Assisted dump configuration details. */
56 int __init
early_init_dt_scan_fw_dump(unsigned long node
,
57 const char *uname
, int depth
, void *data
)
59 const __be32
*sections
;
64 if (depth
!= 1 || strcmp(uname
, "rtas") != 0)
68 * Check if Firmware Assisted dump is supported. if yes, check
69 * if dump has been initiated on last reboot.
71 token
= of_get_flat_dt_prop(node
, "ibm,configure-kernel-dump", NULL
);
75 fw_dump
.fadump_supported
= 1;
76 fw_dump
.ibm_configure_kernel_dump
= be32_to_cpu(*token
);
79 * The 'ibm,kernel-dump' rtas node is present only if there is
80 * dump data waiting for us.
82 fdm_active
= of_get_flat_dt_prop(node
, "ibm,kernel-dump", NULL
);
84 fw_dump
.dump_active
= 1;
86 /* Get the sizes required to store dump data for the firmware provided
88 * For each dump section type supported, a 32bit cell which defines
89 * the ID of a supported section followed by two 32 bit cells which
90 * gives teh size of the section in bytes.
92 sections
= of_get_flat_dt_prop(node
, "ibm,configure-kernel-dump-sizes",
98 num_sections
= size
/ (3 * sizeof(u32
));
100 for (i
= 0; i
< num_sections
; i
++, sections
+= 3) {
101 u32 type
= (u32
)of_read_number(sections
, 1);
104 case FADUMP_CPU_STATE_DATA
:
105 fw_dump
.cpu_state_data_size
=
106 of_read_ulong(§ions
[1], 2);
108 case FADUMP_HPTE_REGION
:
109 fw_dump
.hpte_region_size
=
110 of_read_ulong(§ions
[1], 2);
119 * If fadump is registered, check if the memory provided
120 * falls within boot memory area and reserved memory area.
122 int is_fadump_memory_area(u64 addr
, ulong size
)
124 u64 d_start
= fw_dump
.reserve_dump_area_start
;
125 u64 d_end
= d_start
+ fw_dump
.reserve_dump_area_size
;
127 if (!fw_dump
.dump_registered
)
130 if (((addr
+ size
) > d_start
) && (addr
<= d_end
))
133 return (addr
+ size
) > RMA_START
&& addr
<= fw_dump
.boot_memory_size
;
136 int should_fadump_crash(void)
138 if (!fw_dump
.dump_registered
|| !fw_dump
.fadumphdr_addr
)
143 int is_fadump_active(void)
145 return fw_dump
.dump_active
;
149 * Returns 1, if there are no holes in boot memory area,
152 static int is_boot_memory_area_contiguous(void)
154 struct memblock_region
*reg
;
155 unsigned long tstart
, tend
;
156 unsigned long start_pfn
= PHYS_PFN(RMA_START
);
157 unsigned long end_pfn
= PHYS_PFN(RMA_START
+ fw_dump
.boot_memory_size
);
158 unsigned int ret
= 0;
160 for_each_memblock(memory
, reg
) {
161 tstart
= max(start_pfn
, memblock_region_memory_base_pfn(reg
));
162 tend
= min(end_pfn
, memblock_region_memory_end_pfn(reg
));
164 /* Memory hole from start_pfn to tstart */
165 if (tstart
> start_pfn
)
168 if (tend
== end_pfn
) {
173 start_pfn
= tend
+ 1;
180 /* Print firmware assisted dump configurations for debugging purpose. */
181 static void fadump_show_config(void)
183 pr_debug("Support for firmware-assisted dump (fadump): %s\n",
184 (fw_dump
.fadump_supported
? "present" : "no support"));
186 if (!fw_dump
.fadump_supported
)
189 pr_debug("Fadump enabled : %s\n",
190 (fw_dump
.fadump_enabled
? "yes" : "no"));
191 pr_debug("Dump Active : %s\n",
192 (fw_dump
.dump_active
? "yes" : "no"));
193 pr_debug("Dump section sizes:\n");
194 pr_debug(" CPU state data size: %lx\n", fw_dump
.cpu_state_data_size
);
195 pr_debug(" HPTE region size : %lx\n", fw_dump
.hpte_region_size
);
196 pr_debug("Boot memory size : %lx\n", fw_dump
.boot_memory_size
);
199 static unsigned long init_fadump_mem_struct(struct fadump_mem_struct
*fdm
,
205 memset(fdm
, 0, sizeof(struct fadump_mem_struct
));
206 addr
= addr
& PAGE_MASK
;
208 fdm
->header
.dump_format_version
= cpu_to_be32(0x00000001);
209 fdm
->header
.dump_num_sections
= cpu_to_be16(3);
210 fdm
->header
.dump_status_flag
= 0;
211 fdm
->header
.offset_first_dump_section
=
212 cpu_to_be32((u32
)offsetof(struct fadump_mem_struct
, cpu_state_data
));
215 * Fields for disk dump option.
216 * We are not using disk dump option, hence set these fields to 0.
218 fdm
->header
.dd_block_size
= 0;
219 fdm
->header
.dd_block_offset
= 0;
220 fdm
->header
.dd_num_blocks
= 0;
221 fdm
->header
.dd_offset_disk_path
= 0;
223 /* set 0 to disable an automatic dump-reboot. */
224 fdm
->header
.max_time_auto
= 0;
226 /* Kernel dump sections */
227 /* cpu state data section. */
228 fdm
->cpu_state_data
.request_flag
= cpu_to_be32(FADUMP_REQUEST_FLAG
);
229 fdm
->cpu_state_data
.source_data_type
= cpu_to_be16(FADUMP_CPU_STATE_DATA
);
230 fdm
->cpu_state_data
.source_address
= 0;
231 fdm
->cpu_state_data
.source_len
= cpu_to_be64(fw_dump
.cpu_state_data_size
);
232 fdm
->cpu_state_data
.destination_address
= cpu_to_be64(addr
);
233 addr
+= fw_dump
.cpu_state_data_size
;
235 /* hpte region section */
236 fdm
->hpte_region
.request_flag
= cpu_to_be32(FADUMP_REQUEST_FLAG
);
237 fdm
->hpte_region
.source_data_type
= cpu_to_be16(FADUMP_HPTE_REGION
);
238 fdm
->hpte_region
.source_address
= 0;
239 fdm
->hpte_region
.source_len
= cpu_to_be64(fw_dump
.hpte_region_size
);
240 fdm
->hpte_region
.destination_address
= cpu_to_be64(addr
);
241 addr
+= fw_dump
.hpte_region_size
;
243 /* RMA region section */
244 fdm
->rmr_region
.request_flag
= cpu_to_be32(FADUMP_REQUEST_FLAG
);
245 fdm
->rmr_region
.source_data_type
= cpu_to_be16(FADUMP_REAL_MODE_REGION
);
246 fdm
->rmr_region
.source_address
= cpu_to_be64(RMA_START
);
247 fdm
->rmr_region
.source_len
= cpu_to_be64(fw_dump
.boot_memory_size
);
248 fdm
->rmr_region
.destination_address
= cpu_to_be64(addr
);
249 addr
+= fw_dump
.boot_memory_size
;
255 * fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM
257 * Function to find the largest memory size we need to reserve during early
258 * boot process. This will be the size of the memory that is required for a
259 * kernel to boot successfully.
261 * This function has been taken from phyp-assisted dump feature implementation.
263 * returns larger of 256MB or 5% rounded down to multiples of 256MB.
265 * TODO: Come up with better approach to find out more accurate memory size
266 * that is required for a kernel to boot successfully.
269 static inline unsigned long fadump_calculate_reserve_size(void)
272 unsigned long long base
, size
;
274 if (fw_dump
.reserve_bootvar
)
275 pr_warn("'fadump_reserve_mem=' parameter is deprecated in favor of 'crashkernel=' parameter.\n");
278 * Check if the size is specified through crashkernel= cmdline
279 * option. If yes, then use that but ignore base as fadump reserves
280 * memory at a predefined offset.
282 ret
= parse_crashkernel(boot_command_line
, memblock_phys_mem_size(),
284 if (ret
== 0 && size
> 0) {
285 unsigned long max_size
;
287 if (fw_dump
.reserve_bootvar
)
288 pr_info("Using 'crashkernel=' parameter for memory reservation.\n");
290 fw_dump
.reserve_bootvar
= (unsigned long)size
;
293 * Adjust if the boot memory size specified is above
296 max_size
= memblock_phys_mem_size() / MAX_BOOT_MEM_RATIO
;
297 if (fw_dump
.reserve_bootvar
> max_size
) {
298 fw_dump
.reserve_bootvar
= max_size
;
299 pr_info("Adjusted boot memory size to %luMB\n",
300 (fw_dump
.reserve_bootvar
>> 20));
303 return fw_dump
.reserve_bootvar
;
304 } else if (fw_dump
.reserve_bootvar
) {
306 * 'fadump_reserve_mem=' is being used to reserve memory
307 * for firmware-assisted dump.
309 return fw_dump
.reserve_bootvar
;
312 /* divide by 20 to get 5% of value */
313 size
= memblock_phys_mem_size() / 20;
315 /* round it down in multiples of 256 */
316 size
= size
& ~0x0FFFFFFFUL
;
318 /* Truncate to memory_limit. We don't want to over reserve the memory.*/
319 if (memory_limit
&& size
> memory_limit
)
322 return (size
> MIN_BOOT_MEM
? size
: MIN_BOOT_MEM
);
326 * Calculate the total memory size required to be reserved for
327 * firmware-assisted dump registration.
329 static unsigned long get_fadump_area_size(void)
331 unsigned long size
= 0;
333 size
+= fw_dump
.cpu_state_data_size
;
334 size
+= fw_dump
.hpte_region_size
;
335 size
+= fw_dump
.boot_memory_size
;
336 size
+= sizeof(struct fadump_crash_info_header
);
337 size
+= sizeof(struct elfhdr
); /* ELF core header.*/
338 size
+= sizeof(struct elf_phdr
); /* place holder for cpu notes */
339 /* Program headers for crash memory regions. */
340 size
+= sizeof(struct elf_phdr
) * (memblock_num_regions(memory
) + 2);
342 size
= PAGE_ALIGN(size
);
346 int __init
fadump_reserve_mem(void)
348 unsigned long base
, size
, memory_boundary
;
350 if (!fw_dump
.fadump_enabled
)
353 if (!fw_dump
.fadump_supported
) {
354 printk(KERN_INFO
"Firmware-assisted dump is not supported on"
356 fw_dump
.fadump_enabled
= 0;
360 * Initialize boot memory size
361 * If dump is active then we have already calculated the size during
365 fw_dump
.boot_memory_size
= be64_to_cpu(fdm_active
->rmr_region
.source_len
);
367 fw_dump
.boot_memory_size
= fadump_calculate_reserve_size();
370 * Calculate the memory boundary.
371 * If memory_limit is less than actual memory boundary then reserve
372 * the memory for fadump beyond the memory_limit and adjust the
373 * memory_limit accordingly, so that the running kernel can run with
374 * specified memory_limit.
376 if (memory_limit
&& memory_limit
< memblock_end_of_DRAM()) {
377 size
= get_fadump_area_size();
378 if ((memory_limit
+ size
) < memblock_end_of_DRAM())
379 memory_limit
+= size
;
381 memory_limit
= memblock_end_of_DRAM();
382 printk(KERN_INFO
"Adjusted memory_limit for firmware-assisted"
383 " dump, now %#016llx\n", memory_limit
);
386 memory_boundary
= memory_limit
;
388 memory_boundary
= memblock_end_of_DRAM();
390 if (fw_dump
.dump_active
) {
391 printk(KERN_INFO
"Firmware-assisted dump is active.\n");
393 * If last boot has crashed then reserve all the memory
394 * above boot_memory_size so that we don't touch it until
395 * dump is written to disk by userspace tool. This memory
396 * will be released for general use once the dump is saved.
398 base
= fw_dump
.boot_memory_size
;
399 size
= memory_boundary
- base
;
400 memblock_reserve(base
, size
);
401 printk(KERN_INFO
"Reserved %ldMB of memory at %ldMB "
402 "for saving crash dump\n",
403 (unsigned long)(size
>> 20),
404 (unsigned long)(base
>> 20));
406 fw_dump
.fadumphdr_addr
=
407 be64_to_cpu(fdm_active
->rmr_region
.destination_address
) +
408 be64_to_cpu(fdm_active
->rmr_region
.source_len
);
409 pr_debug("fadumphdr_addr = %p\n",
410 (void *) fw_dump
.fadumphdr_addr
);
412 size
= get_fadump_area_size();
415 * Reserve memory at an offset closer to bottom of the RAM to
416 * minimize the impact of memory hot-remove operation. We can't
417 * use memblock_find_in_range() here since it doesn't allocate
418 * from bottom to top.
420 for (base
= fw_dump
.boot_memory_size
;
421 base
<= (memory_boundary
- size
);
423 if (memblock_is_region_memory(base
, size
) &&
424 !memblock_is_region_reserved(base
, size
))
427 if ((base
> (memory_boundary
- size
)) ||
428 memblock_reserve(base
, size
)) {
429 pr_err("Failed to reserve memory\n");
433 pr_info("Reserved %ldMB of memory at %ldMB for firmware-"
434 "assisted dump (System RAM: %ldMB)\n",
435 (unsigned long)(size
>> 20),
436 (unsigned long)(base
>> 20),
437 (unsigned long)(memblock_phys_mem_size() >> 20));
440 fw_dump
.reserve_dump_area_start
= base
;
441 fw_dump
.reserve_dump_area_size
= size
;
445 unsigned long __init
arch_reserved_kernel_pages(void)
447 return memblock_reserved_size() / PAGE_SIZE
;
450 /* Look for fadump= cmdline option. */
451 static int __init
early_fadump_param(char *p
)
456 if (strncmp(p
, "on", 2) == 0)
457 fw_dump
.fadump_enabled
= 1;
458 else if (strncmp(p
, "off", 3) == 0)
459 fw_dump
.fadump_enabled
= 0;
463 early_param("fadump", early_fadump_param
);
466 * Look for fadump_reserve_mem= cmdline option
467 * TODO: Remove references to 'fadump_reserve_mem=' parameter,
468 * the sooner 'crashkernel=' parameter is accustomed to.
470 static int __init
early_fadump_reserve_mem(char *p
)
473 fw_dump
.reserve_bootvar
= memparse(p
, &p
);
476 early_param("fadump_reserve_mem", early_fadump_reserve_mem
);
478 static int register_fw_dump(struct fadump_mem_struct
*fdm
)
481 unsigned int wait_time
;
483 pr_debug("Registering for firmware-assisted kernel dump...\n");
485 /* TODO: Add upper time limit for the delay */
487 rc
= rtas_call(fw_dump
.ibm_configure_kernel_dump
, 3, 1, NULL
,
488 FADUMP_REGISTER
, fdm
,
489 sizeof(struct fadump_mem_struct
));
491 wait_time
= rtas_busy_delay_time(rc
);
500 pr_err("Failed to register. Unknown Error(%d).\n", rc
);
503 printk(KERN_ERR
"Failed to register firmware-assisted kernel"
504 " dump. Hardware Error(%d).\n", rc
);
507 if (!is_boot_memory_area_contiguous())
508 pr_err("Can't have holes in boot memory area while "
509 "registering fadump\n");
511 printk(KERN_ERR
"Failed to register firmware-assisted kernel"
512 " dump. Parameter Error(%d).\n", rc
);
516 printk(KERN_ERR
"firmware-assisted kernel dump is already "
518 fw_dump
.dump_registered
= 1;
522 printk(KERN_INFO
"firmware-assisted kernel dump registration"
524 fw_dump
.dump_registered
= 1;
531 void crash_fadump(struct pt_regs
*regs
, const char *str
)
533 struct fadump_crash_info_header
*fdh
= NULL
;
534 int old_cpu
, this_cpu
;
536 if (!should_fadump_crash())
540 * old_cpu == -1 means this is the first CPU which has come here,
541 * go ahead and trigger fadump.
543 * old_cpu != -1 means some other CPU has already on it's way
544 * to trigger fadump, just keep looping here.
546 this_cpu
= smp_processor_id();
547 old_cpu
= cmpxchg(&crashing_cpu
, -1, this_cpu
);
551 * We can't loop here indefinitely. Wait as long as fadump
552 * is in force. If we race with fadump un-registration this
553 * loop will break and then we go down to normal panic path
554 * and reboot. If fadump is in force the first crashing
555 * cpu will definitely trigger fadump.
557 while (fw_dump
.dump_registered
)
562 fdh
= __va(fw_dump
.fadumphdr_addr
);
563 fdh
->crashing_cpu
= crashing_cpu
;
564 crash_save_vmcoreinfo();
569 ppc_save_regs(&fdh
->regs
);
571 fdh
->online_mask
= *cpu_online_mask
;
573 /* Call ibm,os-term rtas call to trigger firmware assisted dump */
574 rtas_os_term((char *)str
);
577 #define GPR_MASK 0xffffff0000000000
578 static inline int fadump_gpr_index(u64 id
)
583 if ((id
& GPR_MASK
) == REG_ID("GPR")) {
584 /* get the digits at the end */
589 str
[0] = (id
>> 8) & 0xff;
590 sscanf(str
, "%d", &i
);
597 static inline void fadump_set_regval(struct pt_regs
*regs
, u64 reg_id
,
602 i
= fadump_gpr_index(reg_id
);
604 regs
->gpr
[i
] = (unsigned long)reg_val
;
605 else if (reg_id
== REG_ID("NIA"))
606 regs
->nip
= (unsigned long)reg_val
;
607 else if (reg_id
== REG_ID("MSR"))
608 regs
->msr
= (unsigned long)reg_val
;
609 else if (reg_id
== REG_ID("CTR"))
610 regs
->ctr
= (unsigned long)reg_val
;
611 else if (reg_id
== REG_ID("LR"))
612 regs
->link
= (unsigned long)reg_val
;
613 else if (reg_id
== REG_ID("XER"))
614 regs
->xer
= (unsigned long)reg_val
;
615 else if (reg_id
== REG_ID("CR"))
616 regs
->ccr
= (unsigned long)reg_val
;
617 else if (reg_id
== REG_ID("DAR"))
618 regs
->dar
= (unsigned long)reg_val
;
619 else if (reg_id
== REG_ID("DSISR"))
620 regs
->dsisr
= (unsigned long)reg_val
;
623 static struct fadump_reg_entry
*
624 fadump_read_registers(struct fadump_reg_entry
*reg_entry
, struct pt_regs
*regs
)
626 memset(regs
, 0, sizeof(struct pt_regs
));
628 while (be64_to_cpu(reg_entry
->reg_id
) != REG_ID("CPUEND")) {
629 fadump_set_regval(regs
, be64_to_cpu(reg_entry
->reg_id
),
630 be64_to_cpu(reg_entry
->reg_value
));
637 static u32
*fadump_regs_to_elf_notes(u32
*buf
, struct pt_regs
*regs
)
639 struct elf_prstatus prstatus
;
641 memset(&prstatus
, 0, sizeof(prstatus
));
643 * FIXME: How do i get PID? Do I really need it?
644 * prstatus.pr_pid = ????
646 elf_core_copy_kernel_regs(&prstatus
.pr_reg
, regs
);
647 buf
= append_elf_note(buf
, CRASH_CORE_NOTE_NAME
, NT_PRSTATUS
,
648 &prstatus
, sizeof(prstatus
));
652 static void fadump_update_elfcore_header(char *bufp
)
655 struct elf_phdr
*phdr
;
657 elf
= (struct elfhdr
*)bufp
;
658 bufp
+= sizeof(struct elfhdr
);
660 /* First note is a place holder for cpu notes info. */
661 phdr
= (struct elf_phdr
*)bufp
;
663 if (phdr
->p_type
== PT_NOTE
) {
664 phdr
->p_paddr
= fw_dump
.cpu_notes_buf
;
665 phdr
->p_offset
= phdr
->p_paddr
;
666 phdr
->p_filesz
= fw_dump
.cpu_notes_buf_size
;
667 phdr
->p_memsz
= fw_dump
.cpu_notes_buf_size
;
672 static void *fadump_cpu_notes_buf_alloc(unsigned long size
)
676 unsigned long order
, count
, i
;
678 order
= get_order(size
);
679 vaddr
= (void *)__get_free_pages(GFP_KERNEL
|__GFP_ZERO
, order
);
684 page
= virt_to_page(vaddr
);
685 for (i
= 0; i
< count
; i
++)
686 SetPageReserved(page
+ i
);
690 static void fadump_cpu_notes_buf_free(unsigned long vaddr
, unsigned long size
)
693 unsigned long order
, count
, i
;
695 order
= get_order(size
);
697 page
= virt_to_page(vaddr
);
698 for (i
= 0; i
< count
; i
++)
699 ClearPageReserved(page
+ i
);
700 __free_pages(page
, order
);
704 * Read CPU state dump data and convert it into ELF notes.
705 * The CPU dump starts with magic number "REGSAVE". NumCpusOffset should be
706 * used to access the data to allow for additional fields to be added without
707 * affecting compatibility. Each list of registers for a CPU starts with
708 * "CPUSTRT" and ends with "CPUEND". Each register entry is of 16 bytes,
709 * 8 Byte ASCII identifier and 8 Byte register value. The register entry
710 * with identifier "CPUSTRT" and "CPUEND" contains 4 byte cpu id as part
711 * of register value. For more details refer to PAPR document.
713 * Only for the crashing cpu we ignore the CPU dump data and get exact
714 * state from fadump crash info structure populated by first kernel at the
717 static int __init
fadump_build_cpu_notes(const struct fadump_mem_struct
*fdm
)
719 struct fadump_reg_save_area_header
*reg_header
;
720 struct fadump_reg_entry
*reg_entry
;
721 struct fadump_crash_info_header
*fdh
= NULL
;
724 u32 num_cpus
, *note_buf
;
726 int i
, rc
= 0, cpu
= 0;
728 if (!fdm
->cpu_state_data
.bytes_dumped
)
731 addr
= be64_to_cpu(fdm
->cpu_state_data
.destination_address
);
735 if (be64_to_cpu(reg_header
->magic_number
) != REGSAVE_AREA_MAGIC
) {
736 printk(KERN_ERR
"Unable to read register save area.\n");
739 pr_debug("--------CPU State Data------------\n");
740 pr_debug("Magic Number: %llx\n", be64_to_cpu(reg_header
->magic_number
));
741 pr_debug("NumCpuOffset: %x\n", be32_to_cpu(reg_header
->num_cpu_offset
));
743 vaddr
+= be32_to_cpu(reg_header
->num_cpu_offset
);
744 num_cpus
= be32_to_cpu(*((__be32
*)(vaddr
)));
745 pr_debug("NumCpus : %u\n", num_cpus
);
746 vaddr
+= sizeof(u32
);
747 reg_entry
= (struct fadump_reg_entry
*)vaddr
;
749 /* Allocate buffer to hold cpu crash notes. */
750 fw_dump
.cpu_notes_buf_size
= num_cpus
* sizeof(note_buf_t
);
751 fw_dump
.cpu_notes_buf_size
= PAGE_ALIGN(fw_dump
.cpu_notes_buf_size
);
752 note_buf
= fadump_cpu_notes_buf_alloc(fw_dump
.cpu_notes_buf_size
);
754 printk(KERN_ERR
"Failed to allocate 0x%lx bytes for "
755 "cpu notes buffer\n", fw_dump
.cpu_notes_buf_size
);
758 fw_dump
.cpu_notes_buf
= __pa(note_buf
);
760 pr_debug("Allocated buffer for cpu notes of size %ld at %p\n",
761 (num_cpus
* sizeof(note_buf_t
)), note_buf
);
763 if (fw_dump
.fadumphdr_addr
)
764 fdh
= __va(fw_dump
.fadumphdr_addr
);
766 for (i
= 0; i
< num_cpus
; i
++) {
767 if (be64_to_cpu(reg_entry
->reg_id
) != REG_ID("CPUSTRT")) {
768 printk(KERN_ERR
"Unable to read CPU state data\n");
772 /* Lower 4 bytes of reg_value contains logical cpu id */
773 cpu
= be64_to_cpu(reg_entry
->reg_value
) & FADUMP_CPU_ID_MASK
;
774 if (fdh
&& !cpumask_test_cpu(cpu
, &fdh
->online_mask
)) {
775 SKIP_TO_NEXT_CPU(reg_entry
);
778 pr_debug("Reading register data for cpu %d...\n", cpu
);
779 if (fdh
&& fdh
->crashing_cpu
== cpu
) {
781 note_buf
= fadump_regs_to_elf_notes(note_buf
, ®s
);
782 SKIP_TO_NEXT_CPU(reg_entry
);
785 reg_entry
= fadump_read_registers(reg_entry
, ®s
);
786 note_buf
= fadump_regs_to_elf_notes(note_buf
, ®s
);
789 final_note(note_buf
);
792 pr_debug("Updating elfcore header (%llx) with cpu notes\n",
793 fdh
->elfcorehdr_addr
);
794 fadump_update_elfcore_header((char *)__va(fdh
->elfcorehdr_addr
));
799 fadump_cpu_notes_buf_free((unsigned long)__va(fw_dump
.cpu_notes_buf
),
800 fw_dump
.cpu_notes_buf_size
);
801 fw_dump
.cpu_notes_buf
= 0;
802 fw_dump
.cpu_notes_buf_size
= 0;
808 * Validate and process the dump data stored by firmware before exporting
809 * it through '/proc/vmcore'.
811 static int __init
process_fadump(const struct fadump_mem_struct
*fdm_active
)
813 struct fadump_crash_info_header
*fdh
;
816 if (!fdm_active
|| !fw_dump
.fadumphdr_addr
)
819 /* Check if the dump data is valid. */
820 if ((be16_to_cpu(fdm_active
->header
.dump_status_flag
) == FADUMP_ERROR_FLAG
) ||
821 (fdm_active
->cpu_state_data
.error_flags
!= 0) ||
822 (fdm_active
->rmr_region
.error_flags
!= 0)) {
823 printk(KERN_ERR
"Dump taken by platform is not valid\n");
826 if ((fdm_active
->rmr_region
.bytes_dumped
!=
827 fdm_active
->rmr_region
.source_len
) ||
828 !fdm_active
->cpu_state_data
.bytes_dumped
) {
829 printk(KERN_ERR
"Dump taken by platform is incomplete\n");
833 /* Validate the fadump crash info header */
834 fdh
= __va(fw_dump
.fadumphdr_addr
);
835 if (fdh
->magic_number
!= FADUMP_CRASH_INFO_MAGIC
) {
836 printk(KERN_ERR
"Crash info header is not valid.\n");
840 rc
= fadump_build_cpu_notes(fdm_active
);
845 * We are done validating dump info and elfcore header is now ready
846 * to be exported. set elfcorehdr_addr so that vmcore module will
847 * export the elfcore header through '/proc/vmcore'.
849 elfcorehdr_addr
= fdh
->elfcorehdr_addr
;
854 static void free_crash_memory_ranges(void)
856 kfree(crash_memory_ranges
);
857 crash_memory_ranges
= NULL
;
858 crash_memory_ranges_size
= 0;
859 max_crash_mem_ranges
= 0;
863 * Allocate or reallocate crash memory ranges array in incremental units
866 static int allocate_crash_memory_ranges(void)
868 struct fad_crash_memory_ranges
*new_array
;
871 new_size
= crash_memory_ranges_size
+ PAGE_SIZE
;
872 pr_debug("Allocating %llu bytes of memory for crash memory ranges\n",
875 new_array
= krealloc(crash_memory_ranges
, new_size
, GFP_KERNEL
);
876 if (new_array
== NULL
) {
877 pr_err("Insufficient memory for setting up crash memory ranges\n");
878 free_crash_memory_ranges();
882 crash_memory_ranges
= new_array
;
883 crash_memory_ranges_size
= new_size
;
884 max_crash_mem_ranges
= (new_size
/
885 sizeof(struct fad_crash_memory_ranges
));
889 static inline int fadump_add_crash_memory(unsigned long long base
,
890 unsigned long long end
)
895 if (crash_mem_ranges
== max_crash_mem_ranges
) {
898 ret
= allocate_crash_memory_ranges();
903 pr_debug("crash_memory_range[%d] [%#016llx-%#016llx], %#llx bytes\n",
904 crash_mem_ranges
, base
, end
- 1, (end
- base
));
905 crash_memory_ranges
[crash_mem_ranges
].base
= base
;
906 crash_memory_ranges
[crash_mem_ranges
].size
= end
- base
;
911 static int fadump_exclude_reserved_area(unsigned long long start
,
912 unsigned long long end
)
914 unsigned long long ra_start
, ra_end
;
917 ra_start
= fw_dump
.reserve_dump_area_start
;
918 ra_end
= ra_start
+ fw_dump
.reserve_dump_area_size
;
920 if ((ra_start
< end
) && (ra_end
> start
)) {
921 if ((start
< ra_start
) && (end
> ra_end
)) {
922 ret
= fadump_add_crash_memory(start
, ra_start
);
926 ret
= fadump_add_crash_memory(ra_end
, end
);
927 } else if (start
< ra_start
) {
928 ret
= fadump_add_crash_memory(start
, ra_start
);
929 } else if (ra_end
< end
) {
930 ret
= fadump_add_crash_memory(ra_end
, end
);
933 ret
= fadump_add_crash_memory(start
, end
);
938 static int fadump_init_elfcore_header(char *bufp
)
942 elf
= (struct elfhdr
*) bufp
;
943 bufp
+= sizeof(struct elfhdr
);
944 memcpy(elf
->e_ident
, ELFMAG
, SELFMAG
);
945 elf
->e_ident
[EI_CLASS
] = ELF_CLASS
;
946 elf
->e_ident
[EI_DATA
] = ELF_DATA
;
947 elf
->e_ident
[EI_VERSION
] = EV_CURRENT
;
948 elf
->e_ident
[EI_OSABI
] = ELF_OSABI
;
949 memset(elf
->e_ident
+EI_PAD
, 0, EI_NIDENT
-EI_PAD
);
950 elf
->e_type
= ET_CORE
;
951 elf
->e_machine
= ELF_ARCH
;
952 elf
->e_version
= EV_CURRENT
;
954 elf
->e_phoff
= sizeof(struct elfhdr
);
956 #if defined(_CALL_ELF)
957 elf
->e_flags
= _CALL_ELF
;
961 elf
->e_ehsize
= sizeof(struct elfhdr
);
962 elf
->e_phentsize
= sizeof(struct elf_phdr
);
964 elf
->e_shentsize
= 0;
972 * Traverse through memblock structure and setup crash memory ranges. These
973 * ranges will be used create PT_LOAD program headers in elfcore header.
975 static int fadump_setup_crash_memory_ranges(void)
977 struct memblock_region
*reg
;
978 unsigned long long start
, end
;
981 pr_debug("Setup crash memory ranges.\n");
982 crash_mem_ranges
= 0;
984 * add the first memory chunk (RMA_START through boot_memory_size) as
985 * a separate memory chunk. The reason is, at the time crash firmware
986 * will move the content of this memory chunk to different location
987 * specified during fadump registration. We need to create a separate
988 * program header for this chunk with the correct offset.
990 ret
= fadump_add_crash_memory(RMA_START
, fw_dump
.boot_memory_size
);
994 for_each_memblock(memory
, reg
) {
995 start
= (unsigned long long)reg
->base
;
996 end
= start
+ (unsigned long long)reg
->size
;
999 * skip the first memory chunk that is already added (RMA_START
1000 * through boot_memory_size). This logic needs a relook if and
1001 * when RMA_START changes to a non-zero value.
1003 BUILD_BUG_ON(RMA_START
!= 0);
1004 if (start
< fw_dump
.boot_memory_size
) {
1005 if (end
> fw_dump
.boot_memory_size
)
1006 start
= fw_dump
.boot_memory_size
;
1011 /* add this range excluding the reserved dump area. */
1012 ret
= fadump_exclude_reserved_area(start
, end
);
1021 * If the given physical address falls within the boot memory region then
1022 * return the relocated address that points to the dump region reserved
1023 * for saving initial boot memory contents.
1025 static inline unsigned long fadump_relocate(unsigned long paddr
)
1027 if (paddr
> RMA_START
&& paddr
< fw_dump
.boot_memory_size
)
1028 return be64_to_cpu(fdm
.rmr_region
.destination_address
) + paddr
;
1033 static int fadump_create_elfcore_headers(char *bufp
)
1036 struct elf_phdr
*phdr
;
1039 fadump_init_elfcore_header(bufp
);
1040 elf
= (struct elfhdr
*)bufp
;
1041 bufp
+= sizeof(struct elfhdr
);
1044 * setup ELF PT_NOTE, place holder for cpu notes info. The notes info
1045 * will be populated during second kernel boot after crash. Hence
1046 * this PT_NOTE will always be the first elf note.
1048 * NOTE: Any new ELF note addition should be placed after this note.
1050 phdr
= (struct elf_phdr
*)bufp
;
1051 bufp
+= sizeof(struct elf_phdr
);
1052 phdr
->p_type
= PT_NOTE
;
1064 /* setup ELF PT_NOTE for vmcoreinfo */
1065 phdr
= (struct elf_phdr
*)bufp
;
1066 bufp
+= sizeof(struct elf_phdr
);
1067 phdr
->p_type
= PT_NOTE
;
1072 phdr
->p_paddr
= fadump_relocate(paddr_vmcoreinfo_note());
1073 phdr
->p_offset
= phdr
->p_paddr
;
1074 phdr
->p_memsz
= phdr
->p_filesz
= VMCOREINFO_NOTE_SIZE
;
1076 /* Increment number of program headers. */
1079 /* setup PT_LOAD sections. */
1081 for (i
= 0; i
< crash_mem_ranges
; i
++) {
1082 unsigned long long mbase
, msize
;
1083 mbase
= crash_memory_ranges
[i
].base
;
1084 msize
= crash_memory_ranges
[i
].size
;
1089 phdr
= (struct elf_phdr
*)bufp
;
1090 bufp
+= sizeof(struct elf_phdr
);
1091 phdr
->p_type
= PT_LOAD
;
1092 phdr
->p_flags
= PF_R
|PF_W
|PF_X
;
1093 phdr
->p_offset
= mbase
;
1095 if (mbase
== RMA_START
) {
1097 * The entire RMA region will be moved by firmware
1098 * to the specified destination_address. Hence set
1099 * the correct offset.
1101 phdr
->p_offset
= be64_to_cpu(fdm
.rmr_region
.destination_address
);
1104 phdr
->p_paddr
= mbase
;
1105 phdr
->p_vaddr
= (unsigned long)__va(mbase
);
1106 phdr
->p_filesz
= msize
;
1107 phdr
->p_memsz
= msize
;
1110 /* Increment number of program headers. */
1116 static unsigned long init_fadump_header(unsigned long addr
)
1118 struct fadump_crash_info_header
*fdh
;
1123 fw_dump
.fadumphdr_addr
= addr
;
1125 addr
+= sizeof(struct fadump_crash_info_header
);
1127 memset(fdh
, 0, sizeof(struct fadump_crash_info_header
));
1128 fdh
->magic_number
= FADUMP_CRASH_INFO_MAGIC
;
1129 fdh
->elfcorehdr_addr
= addr
;
1130 /* We will set the crashing cpu id in crash_fadump() during crash. */
1131 fdh
->crashing_cpu
= CPU_UNKNOWN
;
1136 static int register_fadump(void)
1143 * If no memory is reserved then we can not register for firmware-
1146 if (!fw_dump
.reserve_dump_area_size
)
1149 ret
= fadump_setup_crash_memory_ranges();
1153 addr
= be64_to_cpu(fdm
.rmr_region
.destination_address
) + be64_to_cpu(fdm
.rmr_region
.source_len
);
1154 /* Initialize fadump crash info header. */
1155 addr
= init_fadump_header(addr
);
1158 pr_debug("Creating ELF core headers at %#016lx\n", addr
);
1159 fadump_create_elfcore_headers(vaddr
);
1161 /* register the future kernel dump with firmware. */
1162 return register_fw_dump(&fdm
);
1165 static int fadump_unregister_dump(struct fadump_mem_struct
*fdm
)
1168 unsigned int wait_time
;
1170 pr_debug("Un-register firmware-assisted dump\n");
1172 /* TODO: Add upper time limit for the delay */
1174 rc
= rtas_call(fw_dump
.ibm_configure_kernel_dump
, 3, 1, NULL
,
1175 FADUMP_UNREGISTER
, fdm
,
1176 sizeof(struct fadump_mem_struct
));
1178 wait_time
= rtas_busy_delay_time(rc
);
1181 } while (wait_time
);
1184 printk(KERN_ERR
"Failed to un-register firmware-assisted dump."
1185 " unexpected error(%d).\n", rc
);
1188 fw_dump
.dump_registered
= 0;
1192 static int fadump_invalidate_dump(struct fadump_mem_struct
*fdm
)
1195 unsigned int wait_time
;
1197 pr_debug("Invalidating firmware-assisted dump registration\n");
1199 /* TODO: Add upper time limit for the delay */
1201 rc
= rtas_call(fw_dump
.ibm_configure_kernel_dump
, 3, 1, NULL
,
1202 FADUMP_INVALIDATE
, fdm
,
1203 sizeof(struct fadump_mem_struct
));
1205 wait_time
= rtas_busy_delay_time(rc
);
1208 } while (wait_time
);
1211 pr_err("Failed to invalidate firmware-assisted dump registration. Unexpected error (%d).\n", rc
);
1214 fw_dump
.dump_active
= 0;
1219 void fadump_cleanup(void)
1221 /* Invalidate the registration only if dump is active. */
1222 if (fw_dump
.dump_active
) {
1223 init_fadump_mem_struct(&fdm
,
1224 be64_to_cpu(fdm_active
->cpu_state_data
.destination_address
));
1225 fadump_invalidate_dump(&fdm
);
1226 } else if (fw_dump
.dump_registered
) {
1227 /* Un-register Firmware-assisted dump if it was registered. */
1228 fadump_unregister_dump(&fdm
);
1229 free_crash_memory_ranges();
1233 static void fadump_free_reserved_memory(unsigned long start_pfn
,
1234 unsigned long end_pfn
)
1237 unsigned long time_limit
= jiffies
+ HZ
;
1239 pr_info("freeing reserved memory (0x%llx - 0x%llx)\n",
1240 PFN_PHYS(start_pfn
), PFN_PHYS(end_pfn
));
1242 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
1243 free_reserved_page(pfn_to_page(pfn
));
1245 if (time_after(jiffies
, time_limit
)) {
1247 time_limit
= jiffies
+ HZ
;
1253 * Skip memory holes and free memory that was actually reserved.
1255 static void fadump_release_reserved_area(unsigned long start
, unsigned long end
)
1257 struct memblock_region
*reg
;
1258 unsigned long tstart
, tend
;
1259 unsigned long start_pfn
= PHYS_PFN(start
);
1260 unsigned long end_pfn
= PHYS_PFN(end
);
1262 for_each_memblock(memory
, reg
) {
1263 tstart
= max(start_pfn
, memblock_region_memory_base_pfn(reg
));
1264 tend
= min(end_pfn
, memblock_region_memory_end_pfn(reg
));
1265 if (tstart
< tend
) {
1266 fadump_free_reserved_memory(tstart
, tend
);
1268 if (tend
== end_pfn
)
1271 start_pfn
= tend
+ 1;
1277 * Release the memory that was reserved in early boot to preserve the memory
1278 * contents. The released memory will be available for general use.
1280 static void fadump_release_memory(unsigned long begin
, unsigned long end
)
1282 unsigned long ra_start
, ra_end
;
1284 ra_start
= fw_dump
.reserve_dump_area_start
;
1285 ra_end
= ra_start
+ fw_dump
.reserve_dump_area_size
;
1288 * exclude the dump reserve area. Will reuse it for next
1289 * fadump registration.
1291 if (begin
< ra_end
&& end
> ra_start
) {
1292 if (begin
< ra_start
)
1293 fadump_release_reserved_area(begin
, ra_start
);
1295 fadump_release_reserved_area(ra_end
, end
);
1297 fadump_release_reserved_area(begin
, end
);
1300 static void fadump_invalidate_release_mem(void)
1302 unsigned long reserved_area_start
, reserved_area_end
;
1303 unsigned long destination_address
;
1305 mutex_lock(&fadump_mutex
);
1306 if (!fw_dump
.dump_active
) {
1307 mutex_unlock(&fadump_mutex
);
1311 destination_address
= be64_to_cpu(fdm_active
->cpu_state_data
.destination_address
);
1313 mutex_unlock(&fadump_mutex
);
1316 * Save the current reserved memory bounds we will require them
1317 * later for releasing the memory for general use.
1319 reserved_area_start
= fw_dump
.reserve_dump_area_start
;
1320 reserved_area_end
= reserved_area_start
+
1321 fw_dump
.reserve_dump_area_size
;
1323 * Setup reserve_dump_area_start and its size so that we can
1324 * reuse this reserved memory for Re-registration.
1326 fw_dump
.reserve_dump_area_start
= destination_address
;
1327 fw_dump
.reserve_dump_area_size
= get_fadump_area_size();
1329 fadump_release_memory(reserved_area_start
, reserved_area_end
);
1330 if (fw_dump
.cpu_notes_buf
) {
1331 fadump_cpu_notes_buf_free(
1332 (unsigned long)__va(fw_dump
.cpu_notes_buf
),
1333 fw_dump
.cpu_notes_buf_size
);
1334 fw_dump
.cpu_notes_buf
= 0;
1335 fw_dump
.cpu_notes_buf_size
= 0;
1337 /* Initialize the kernel dump memory structure for FAD registration. */
1338 init_fadump_mem_struct(&fdm
, fw_dump
.reserve_dump_area_start
);
1341 static ssize_t
fadump_release_memory_store(struct kobject
*kobj
,
1342 struct kobj_attribute
*attr
,
1343 const char *buf
, size_t count
)
1347 if (!fw_dump
.dump_active
)
1350 if (kstrtoint(buf
, 0, &input
))
1355 * Take away the '/proc/vmcore'. We are releasing the dump
1356 * memory, hence it will not be valid anymore.
1358 #ifdef CONFIG_PROC_VMCORE
1361 fadump_invalidate_release_mem();
1368 static ssize_t
fadump_enabled_show(struct kobject
*kobj
,
1369 struct kobj_attribute
*attr
,
1372 return sprintf(buf
, "%d\n", fw_dump
.fadump_enabled
);
1375 static ssize_t
fadump_register_show(struct kobject
*kobj
,
1376 struct kobj_attribute
*attr
,
1379 return sprintf(buf
, "%d\n", fw_dump
.dump_registered
);
1382 static ssize_t
fadump_register_store(struct kobject
*kobj
,
1383 struct kobj_attribute
*attr
,
1384 const char *buf
, size_t count
)
1389 if (!fw_dump
.fadump_enabled
|| fdm_active
)
1392 if (kstrtoint(buf
, 0, &input
))
1395 mutex_lock(&fadump_mutex
);
1399 if (fw_dump
.dump_registered
== 0) {
1402 /* Un-register Firmware-assisted dump */
1403 fadump_unregister_dump(&fdm
);
1406 if (fw_dump
.dump_registered
== 1) {
1410 /* Register Firmware-assisted dump */
1411 ret
= register_fadump();
1419 mutex_unlock(&fadump_mutex
);
1420 return ret
< 0 ? ret
: count
;
1423 static int fadump_region_show(struct seq_file
*m
, void *private)
1425 const struct fadump_mem_struct
*fdm_ptr
;
1427 if (!fw_dump
.fadump_enabled
)
1430 mutex_lock(&fadump_mutex
);
1432 fdm_ptr
= fdm_active
;
1434 mutex_unlock(&fadump_mutex
);
1439 "CPU : [%#016llx-%#016llx] %#llx bytes, "
1441 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
),
1442 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
) +
1443 be64_to_cpu(fdm_ptr
->cpu_state_data
.source_len
) - 1,
1444 be64_to_cpu(fdm_ptr
->cpu_state_data
.source_len
),
1445 be64_to_cpu(fdm_ptr
->cpu_state_data
.bytes_dumped
));
1447 "HPTE: [%#016llx-%#016llx] %#llx bytes, "
1449 be64_to_cpu(fdm_ptr
->hpte_region
.destination_address
),
1450 be64_to_cpu(fdm_ptr
->hpte_region
.destination_address
) +
1451 be64_to_cpu(fdm_ptr
->hpte_region
.source_len
) - 1,
1452 be64_to_cpu(fdm_ptr
->hpte_region
.source_len
),
1453 be64_to_cpu(fdm_ptr
->hpte_region
.bytes_dumped
));
1455 "DUMP: [%#016llx-%#016llx] %#llx bytes, "
1457 be64_to_cpu(fdm_ptr
->rmr_region
.destination_address
),
1458 be64_to_cpu(fdm_ptr
->rmr_region
.destination_address
) +
1459 be64_to_cpu(fdm_ptr
->rmr_region
.source_len
) - 1,
1460 be64_to_cpu(fdm_ptr
->rmr_region
.source_len
),
1461 be64_to_cpu(fdm_ptr
->rmr_region
.bytes_dumped
));
1464 (fw_dump
.reserve_dump_area_start
==
1465 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
)))
1468 /* Dump is active. Show reserved memory region. */
1470 " : [%#016llx-%#016llx] %#llx bytes, "
1472 (unsigned long long)fw_dump
.reserve_dump_area_start
,
1473 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
) - 1,
1474 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
) -
1475 fw_dump
.reserve_dump_area_start
,
1476 be64_to_cpu(fdm_ptr
->cpu_state_data
.destination_address
) -
1477 fw_dump
.reserve_dump_area_start
);
1480 mutex_unlock(&fadump_mutex
);
1484 static struct kobj_attribute fadump_release_attr
= __ATTR(fadump_release_mem
,
1486 fadump_release_memory_store
);
1487 static struct kobj_attribute fadump_attr
= __ATTR(fadump_enabled
,
1488 0444, fadump_enabled_show
,
1490 static struct kobj_attribute fadump_register_attr
= __ATTR(fadump_registered
,
1491 0644, fadump_register_show
,
1492 fadump_register_store
);
1494 static int fadump_region_open(struct inode
*inode
, struct file
*file
)
1496 return single_open(file
, fadump_region_show
, inode
->i_private
);
1499 static const struct file_operations fadump_region_fops
= {
1500 .open
= fadump_region_open
,
1502 .llseek
= seq_lseek
,
1503 .release
= single_release
,
1506 static void fadump_init_files(void)
1508 struct dentry
*debugfs_file
;
1511 rc
= sysfs_create_file(kernel_kobj
, &fadump_attr
.attr
);
1513 printk(KERN_ERR
"fadump: unable to create sysfs file"
1514 " fadump_enabled (%d)\n", rc
);
1516 rc
= sysfs_create_file(kernel_kobj
, &fadump_register_attr
.attr
);
1518 printk(KERN_ERR
"fadump: unable to create sysfs file"
1519 " fadump_registered (%d)\n", rc
);
1521 debugfs_file
= debugfs_create_file("fadump_region", 0444,
1522 powerpc_debugfs_root
, NULL
,
1523 &fadump_region_fops
);
1525 printk(KERN_ERR
"fadump: unable to create debugfs file"
1526 " fadump_region\n");
1528 if (fw_dump
.dump_active
) {
1529 rc
= sysfs_create_file(kernel_kobj
, &fadump_release_attr
.attr
);
1531 printk(KERN_ERR
"fadump: unable to create sysfs file"
1532 " fadump_release_mem (%d)\n", rc
);
1538 * Prepare for firmware-assisted dump.
1540 int __init
setup_fadump(void)
1542 if (!fw_dump
.fadump_enabled
)
1545 if (!fw_dump
.fadump_supported
) {
1546 printk(KERN_ERR
"Firmware-assisted dump is not supported on"
1547 " this hardware\n");
1551 fadump_show_config();
1553 * If dump data is available then see if it is valid and prepare for
1554 * saving it to the disk.
1556 if (fw_dump
.dump_active
) {
1558 * if dump process fails then invalidate the registration
1559 * and release memory before proceeding for re-registration.
1561 if (process_fadump(fdm_active
) < 0)
1562 fadump_invalidate_release_mem();
1564 /* Initialize the kernel dump memory structure for FAD registration. */
1565 else if (fw_dump
.reserve_dump_area_size
)
1566 init_fadump_mem_struct(&fdm
, fw_dump
.reserve_dump_area_start
);
1567 fadump_init_files();
1571 subsys_initcall(setup_fadump
);