Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
5033cba0 | 2 | /* |
62a31a03 | 3 | * Architecture specific (i386/x86_64) functions for kexec based crash dumps. |
5033cba0 EB |
4 | * |
5 | * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) | |
6 | * | |
7 | * Copyright (C) IBM Corporation, 2004. All rights reserved. | |
dd5f7260 VG |
8 | * Copyright (C) Red Hat Inc., 2014. All rights reserved. |
9 | * Authors: | |
10 | * Vivek Goyal <vgoyal@redhat.com> | |
5033cba0 EB |
11 | * |
12 | */ | |
13 | ||
dd5f7260 VG |
14 | #define pr_fmt(fmt) "kexec: " fmt |
15 | ||
5033cba0 EB |
16 | #include <linux/types.h> |
17 | #include <linux/kernel.h> | |
18 | #include <linux/smp.h> | |
5033cba0 EB |
19 | #include <linux/reboot.h> |
20 | #include <linux/kexec.h> | |
5033cba0 EB |
21 | #include <linux/delay.h> |
22 | #include <linux/elf.h> | |
23 | #include <linux/elfcore.h> | |
186f4360 | 24 | #include <linux/export.h> |
dd5f7260 | 25 | #include <linux/slab.h> |
d6472302 | 26 | #include <linux/vmalloc.h> |
6f599d84 | 27 | #include <linux/memblock.h> |
5033cba0 | 28 | |
103bf75f | 29 | #include <asm/bootparam.h> |
5033cba0 EB |
30 | #include <asm/processor.h> |
31 | #include <asm/hardirq.h> | |
32 | #include <asm/nmi.h> | |
33 | #include <asm/hw_irq.h> | |
19842d67 | 34 | #include <asm/apic.h> |
5520b7e7 | 35 | #include <asm/e820/types.h> |
8643e28d | 36 | #include <asm/io_apic.h> |
0c1b2724 | 37 | #include <asm/hpet.h> |
1eeb66a1 | 38 | #include <linux/kdebug.h> |
96b89dc6 | 39 | #include <asm/cpu.h> |
ed23dc6f | 40 | #include <asm/reboot.h> |
da06a43d | 41 | #include <asm/intel_pt.h> |
89f579ce | 42 | #include <asm/crash.h> |
6f599d84 | 43 | #include <asm/cmdline.h> |
8ef97958 | 44 | #include <asm/sev.h> |
8e294786 | 45 | |
dd5f7260 VG |
46 | /* Used while preparing memory map entries for second kernel */ |
47 | struct crash_memmap_data { | |
48 | struct boot_params *params; | |
49 | /* Type of memory */ | |
50 | unsigned int type; | |
51 | }; | |
52 | ||
b2bbe71b EH |
53 | #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) |
54 | ||
9c48f1c6 | 55 | static void kdump_nmi_callback(int cpu, struct pt_regs *regs) |
c4ac4263 | 56 | { |
a7d41820 EH |
57 | crash_save_cpu(regs, cpu); |
58 | ||
da06a43d TI |
59 | /* |
60 | * Disable Intel PT to stop its logging | |
61 | */ | |
62 | cpu_emergency_stop_pt(); | |
63 | ||
8ef97958 AK |
64 | kdump_sev_callback(); |
65 | ||
a7d41820 EH |
66 | disable_local_APIC(); |
67 | } | |
68 | ||
0ee59413 | 69 | void kdump_nmi_shootdown_cpus(void) |
d1e7b91c | 70 | { |
8e294786 | 71 | nmi_shootdown_cpus(kdump_nmi_callback); |
d1e7b91c | 72 | |
19842d67 | 73 | disable_local_APIC(); |
c4ac4263 | 74 | } |
d1e7b91c | 75 | |
0ee59413 HK |
76 | /* Override the weak function in kernel/panic.c */ |
77 | void crash_smp_send_stop(void) | |
78 | { | |
79 | static int cpus_stopped; | |
80 | ||
81 | if (cpus_stopped) | |
82 | return; | |
83 | ||
84 | if (smp_ops.crash_stop_other_cpus) | |
85 | smp_ops.crash_stop_other_cpus(); | |
86 | else | |
87 | smp_send_stop(); | |
88 | ||
89 | cpus_stopped = 1; | |
90 | } | |
91 | ||
c4ac4263 | 92 | #else |
0ee59413 | 93 | void crash_smp_send_stop(void) |
c4ac4263 EB |
94 | { |
95 | /* There are no cpus to shootdown */ | |
96 | } | |
97 | #endif | |
98 | ||
ed23dc6f | 99 | void native_machine_crash_shutdown(struct pt_regs *regs) |
5033cba0 EB |
100 | { |
101 | /* This function is only called after the system | |
f18190bd | 102 | * has panicked or is otherwise in a critical state. |
5033cba0 EB |
103 | * The minimum amount of code to allow a kexec'd kernel |
104 | * to run successfully needs to happen here. | |
105 | * | |
106 | * In practice this means shooting down the other cpus in | |
107 | * an SMP system. | |
108 | */ | |
c4ac4263 EB |
109 | /* The kernel is broken so disable interrupts */ |
110 | local_irq_disable(); | |
a3ea8ac8 | 111 | |
0ee59413 | 112 | crash_smp_send_stop(); |
2340b62f | 113 | |
26044aff | 114 | cpu_emergency_disable_virtualization(); |
2340b62f | 115 | |
da06a43d TI |
116 | /* |
117 | * Disable Intel PT to stop its logging | |
118 | */ | |
119 | cpu_emergency_stop_pt(); | |
120 | ||
17405453 YY |
121 | #ifdef CONFIG_X86_IO_APIC |
122 | /* Prevent crash_kexec() from deadlocking on ioapic_lock. */ | |
123 | ioapic_zap_locks(); | |
339b2ae0 | 124 | clear_IO_APIC(); |
0c1b2724 | 125 | #endif |
522e6646 | 126 | lapic_shutdown(); |
339b2ae0 | 127 | restore_boot_irq_mode(); |
0c1b2724 OH |
128 | #ifdef CONFIG_HPET_TIMER |
129 | hpet_disable(); | |
19842d67 | 130 | #endif |
22daa422 KS |
131 | |
132 | /* | |
133 | * Non-crash kexec calls enc_kexec_begin() while scheduling is still | |
134 | * active. This allows the callback to wait until all in-flight | |
135 | * shared<->private conversions are complete. In a crash scenario, | |
136 | * enc_kexec_begin() gets called after all but one CPU have been shut | |
137 | * down and interrupts have been disabled. This allows the callback to | |
138 | * detect a race with the conversion and report it. | |
139 | */ | |
140 | x86_platform.guest.enc_kexec_begin(); | |
141 | x86_platform.guest.enc_kexec_finish(); | |
142 | ||
85916f81 | 143 | crash_save_cpu(regs, safe_smp_processor_id()); |
5033cba0 | 144 | } |
dd5f7260 | 145 | |
ea53ad9c | 146 | #if defined(CONFIG_KEXEC_FILE) || defined(CONFIG_CRASH_HOTPLUG) |
1d2e733b | 147 | static int get_nr_ram_ranges_callback(struct resource *res, void *arg) |
dd5f7260 | 148 | { |
e3c41e37 | 149 | unsigned int *nr_ranges = arg; |
dd5f7260 VG |
150 | |
151 | (*nr_ranges)++; | |
152 | return 0; | |
153 | } | |
154 | ||
dd5f7260 | 155 | /* Gather all the required information to prepare elf headers for ram regions */ |
8d5f894a | 156 | static struct crash_mem *fill_up_crash_elf_data(void) |
dd5f7260 VG |
157 | { |
158 | unsigned int nr_ranges = 0; | |
8d5f894a | 159 | struct crash_mem *cmem; |
dd5f7260 | 160 | |
9eff3037 | 161 | walk_system_ram_res(0, -1, &nr_ranges, get_nr_ram_ranges_callback); |
8d5f894a AT |
162 | if (!nr_ranges) |
163 | return NULL; | |
dd5f7260 | 164 | |
8d5f894a AT |
165 | /* |
166 | * Exclusion of crash region and/or crashk_low_res may cause | |
167 | * another range split. So add extra two slots here. | |
168 | */ | |
169 | nr_ranges += 2; | |
4df43095 | 170 | cmem = vzalloc(struct_size(cmem, ranges, nr_ranges)); |
8d5f894a AT |
171 | if (!cmem) |
172 | return NULL; | |
dd5f7260 | 173 | |
8d5f894a AT |
174 | cmem->max_nr_ranges = nr_ranges; |
175 | cmem->nr_ranges = 0; | |
dd5f7260 | 176 | |
8d5f894a | 177 | return cmem; |
dd5f7260 VG |
178 | } |
179 | ||
dd5f7260 VG |
180 | /* |
181 | * Look for any unwanted ranges between mstart, mend and remove them. This | |
8d5f894a | 182 | * might lead to split and split ranges are put in cmem->ranges[] array |
dd5f7260 | 183 | */ |
8d5f894a | 184 | static int elf_header_exclude_ranges(struct crash_mem *cmem) |
dd5f7260 | 185 | { |
dd5f7260 VG |
186 | int ret = 0; |
187 | ||
7c321eb2 | 188 | /* Exclude the low 1M because it is always reserved */ |
61bb219f | 189 | ret = crash_exclude_mem_range(cmem, 0, SZ_1M - 1); |
7c321eb2 LJ |
190 | if (ret) |
191 | return ret; | |
192 | ||
dd5f7260 | 193 | /* Exclude crashkernel region */ |
babac4a8 | 194 | ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); |
dd5f7260 VG |
195 | if (ret) |
196 | return ret; | |
197 | ||
9eff3037 | 198 | if (crashk_low_res.end) |
babac4a8 | 199 | ret = crash_exclude_mem_range(cmem, crashk_low_res.start, |
9eff3037 | 200 | crashk_low_res.end); |
dd5f7260 | 201 | |
dd5f7260 VG |
202 | return ret; |
203 | } | |
204 | ||
1d2e733b | 205 | static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg) |
dd5f7260 | 206 | { |
8d5f894a | 207 | struct crash_mem *cmem = arg; |
dd5f7260 | 208 | |
cbe66016 AT |
209 | cmem->ranges[cmem->nr_ranges].start = res->start; |
210 | cmem->ranges[cmem->nr_ranges].end = res->end; | |
211 | cmem->nr_ranges++; | |
dd5f7260 | 212 | |
cbe66016 | 213 | return 0; |
dd5f7260 VG |
214 | } |
215 | ||
dd5f7260 | 216 | /* Prepare elf headers. Return addr and size */ |
83d4a42a YW |
217 | static int prepare_elf_headers(void **addr, unsigned long *sz, |
218 | unsigned long *nr_mem_ranges) | |
dd5f7260 | 219 | { |
8d5f894a | 220 | struct crash_mem *cmem; |
7c321eb2 | 221 | int ret; |
dd5f7260 | 222 | |
8d5f894a AT |
223 | cmem = fill_up_crash_elf_data(); |
224 | if (!cmem) | |
dd5f7260 VG |
225 | return -ENOMEM; |
226 | ||
9eff3037 | 227 | ret = walk_system_ram_res(0, -1, cmem, prepare_elf64_ram_headers_callback); |
cbe66016 AT |
228 | if (ret) |
229 | goto out; | |
230 | ||
231 | /* Exclude unwanted mem ranges */ | |
8d5f894a | 232 | ret = elf_header_exclude_ranges(cmem); |
cbe66016 AT |
233 | if (ret) |
234 | goto out; | |
235 | ||
ea53ad9c ED |
236 | /* Return the computed number of memory ranges, for hotplug usage */ |
237 | *nr_mem_ranges = cmem->nr_ranges; | |
238 | ||
dd5f7260 | 239 | /* By default prepare 64bit headers */ |
83d4a42a | 240 | ret = crash_prepare_elf64_headers(cmem, IS_ENABLED(CONFIG_X86_64), addr, sz); |
cbe66016 | 241 | |
cbe66016 | 242 | out: |
8d5f894a | 243 | vfree(cmem); |
dd5f7260 VG |
244 | return ret; |
245 | } | |
ea53ad9c | 246 | #endif |
dd5f7260 | 247 | |
ea53ad9c | 248 | #ifdef CONFIG_KEXEC_FILE |
8ec67d97 | 249 | static int add_e820_entry(struct boot_params *params, struct e820_entry *entry) |
dd5f7260 VG |
250 | { |
251 | unsigned int nr_e820_entries; | |
252 | ||
253 | nr_e820_entries = params->e820_entries; | |
08b46d5d | 254 | if (nr_e820_entries >= E820_MAX_ENTRIES_ZEROPAGE) |
dd5f7260 VG |
255 | return 1; |
256 | ||
9eff3037 | 257 | memcpy(¶ms->e820_table[nr_e820_entries], entry, sizeof(struct e820_entry)); |
dd5f7260 VG |
258 | params->e820_entries++; |
259 | return 0; | |
260 | } | |
261 | ||
1d2e733b | 262 | static int memmap_entry_callback(struct resource *res, void *arg) |
dd5f7260 VG |
263 | { |
264 | struct crash_memmap_data *cmd = arg; | |
265 | struct boot_params *params = cmd->params; | |
8ec67d97 | 266 | struct e820_entry ei; |
dd5f7260 | 267 | |
1d2e733b | 268 | ei.addr = res->start; |
9275b933 | 269 | ei.size = resource_size(res); |
dd5f7260 VG |
270 | ei.type = cmd->type; |
271 | add_e820_entry(params, &ei); | |
272 | ||
273 | return 0; | |
274 | } | |
275 | ||
276 | static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem, | |
277 | unsigned long long mstart, | |
278 | unsigned long long mend) | |
279 | { | |
280 | unsigned long start, end; | |
dd5f7260 VG |
281 | |
282 | cmem->ranges[0].start = mstart; | |
283 | cmem->ranges[0].end = mend; | |
284 | cmem->nr_ranges = 1; | |
285 | ||
dd5f7260 | 286 | /* Exclude elf header region */ |
179350f0 LR |
287 | start = image->elf_load_addr; |
288 | end = start + image->elf_headers_sz - 1; | |
babac4a8 | 289 | return crash_exclude_mem_range(cmem, start, end); |
dd5f7260 VG |
290 | } |
291 | ||
292 | /* Prepare memory map for crash dump kernel */ | |
293 | int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params) | |
294 | { | |
295 | int i, ret = 0; | |
296 | unsigned long flags; | |
8ec67d97 | 297 | struct e820_entry ei; |
dd5f7260 VG |
298 | struct crash_memmap_data cmd; |
299 | struct crash_mem *cmem; | |
300 | ||
5849cdf8 | 301 | cmem = vzalloc(struct_size(cmem, ranges, 1)); |
dd5f7260 VG |
302 | if (!cmem) |
303 | return -ENOMEM; | |
304 | ||
305 | memset(&cmd, 0, sizeof(struct crash_memmap_data)); | |
306 | cmd.params = params; | |
307 | ||
7c321eb2 LJ |
308 | /* Add the low 1M */ |
309 | cmd.type = E820_TYPE_RAM; | |
310 | flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; | |
311 | walk_iomem_res_desc(IORES_DESC_NONE, flags, 0, (1<<20)-1, &cmd, | |
9eff3037 | 312 | memmap_entry_callback); |
dd5f7260 VG |
313 | |
314 | /* Add ACPI tables */ | |
09821ff1 | 315 | cmd.type = E820_TYPE_ACPI; |
dd5f7260 | 316 | flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
f0f4711a | 317 | walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1, &cmd, |
9eff3037 | 318 | memmap_entry_callback); |
dd5f7260 VG |
319 | |
320 | /* Add ACPI Non-volatile Storage */ | |
09821ff1 | 321 | cmd.type = E820_TYPE_NVS; |
f0f4711a | 322 | walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1, &cmd, |
9eff3037 | 323 | memmap_entry_callback); |
dd5f7260 | 324 | |
980621da LJ |
325 | /* Add e820 reserved ranges */ |
326 | cmd.type = E820_TYPE_RESERVED; | |
327 | flags = IORESOURCE_MEM; | |
328 | walk_iomem_res_desc(IORES_DESC_RESERVED, flags, 0, -1, &cmd, | |
9eff3037 | 329 | memmap_entry_callback); |
980621da | 330 | |
dd5f7260 VG |
331 | /* Add crashk_low_res region */ |
332 | if (crashk_low_res.end) { | |
333 | ei.addr = crashk_low_res.start; | |
1429b568 | 334 | ei.size = resource_size(&crashk_low_res); |
09821ff1 | 335 | ei.type = E820_TYPE_RAM; |
dd5f7260 VG |
336 | add_e820_entry(params, &ei); |
337 | } | |
338 | ||
339 | /* Exclude some ranges from crashk_res and add rest to memmap */ | |
9eff3037 | 340 | ret = memmap_exclude_ranges(image, cmem, crashk_res.start, crashk_res.end); |
dd5f7260 VG |
341 | if (ret) |
342 | goto out; | |
343 | ||
344 | for (i = 0; i < cmem->nr_ranges; i++) { | |
345 | ei.size = cmem->ranges[i].end - cmem->ranges[i].start + 1; | |
346 | ||
347 | /* If entry is less than a page, skip it */ | |
348 | if (ei.size < PAGE_SIZE) | |
349 | continue; | |
350 | ei.addr = cmem->ranges[i].start; | |
09821ff1 | 351 | ei.type = E820_TYPE_RAM; |
dd5f7260 VG |
352 | add_e820_entry(params, &ei); |
353 | } | |
354 | ||
355 | out: | |
356 | vfree(cmem); | |
357 | return ret; | |
358 | } | |
359 | ||
dd5f7260 VG |
360 | int crash_load_segments(struct kimage *image) |
361 | { | |
dd5f7260 | 362 | int ret; |
ea53ad9c | 363 | unsigned long pnum = 0; |
ec2b9bfa TJB |
364 | struct kexec_buf kbuf = { .image = image, .buf_min = 0, |
365 | .buf_max = ULONG_MAX, .top_down = false }; | |
dd5f7260 | 366 | |
dd5f7260 | 367 | /* Prepare elf headers and add a segment */ |
83d4a42a | 368 | ret = prepare_elf_headers(&kbuf.buffer, &kbuf.bufsz, &pnum); |
dd5f7260 VG |
369 | if (ret) |
370 | return ret; | |
371 | ||
ea53ad9c ED |
372 | image->elf_headers = kbuf.buffer; |
373 | image->elf_headers_sz = kbuf.bufsz; | |
374 | kbuf.memsz = kbuf.bufsz; | |
375 | ||
376 | #ifdef CONFIG_CRASH_HOTPLUG | |
377 | /* | |
378 | * The elfcorehdr segment size accounts for VMCOREINFO, kernel_map, | |
379 | * maximum CPUs and maximum memory ranges. | |
380 | */ | |
381 | if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG)) | |
382 | pnum = 2 + CONFIG_NR_CPUS_DEFAULT + CONFIG_CRASH_MAX_MEMORY_RANGES; | |
383 | else | |
384 | pnum += 2 + CONFIG_NR_CPUS_DEFAULT; | |
385 | ||
386 | if (pnum < (unsigned long)PN_XNUM) { | |
387 | kbuf.memsz = pnum * sizeof(Elf64_Phdr); | |
388 | kbuf.memsz += sizeof(Elf64_Ehdr); | |
389 | ||
390 | image->elfcorehdr_index = image->nr_segments; | |
391 | ||
392 | /* Mark as usable to crash kernel, else crash kernel fails on boot */ | |
393 | image->elf_headers_sz = kbuf.memsz; | |
394 | } else { | |
395 | pr_err("number of Phdrs %lu exceeds max\n", pnum); | |
396 | } | |
397 | #endif | |
dd5f7260 | 398 | |
ec2b9bfa | 399 | kbuf.buf_align = ELF_CORE_HEADER_ALIGN; |
993a1103 | 400 | kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; |
ec2b9bfa | 401 | ret = kexec_add_buffer(&kbuf); |
d00dd2f2 | 402 | if (ret) |
dd5f7260 | 403 | return ret; |
179350f0 | 404 | image->elf_load_addr = kbuf.mem; |
e687b2fa BH |
405 | kexec_dprintk("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n", |
406 | image->elf_load_addr, kbuf.bufsz, kbuf.memsz); | |
dd5f7260 VG |
407 | |
408 | return ret; | |
409 | } | |
74ca317c | 410 | #endif /* CONFIG_KEXEC_FILE */ |
ea53ad9c ED |
411 | |
412 | #ifdef CONFIG_CRASH_HOTPLUG | |
413 | ||
414 | #undef pr_fmt | |
415 | #define pr_fmt(fmt) "crash hp: " fmt | |
416 | ||
79365026 | 417 | int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags) |
a72bbec7 | 418 | { |
a72bbec7 | 419 | |
79365026 SJ |
420 | #ifdef CONFIG_KEXEC_FILE |
421 | if (image->file_mode) | |
422 | return 1; | |
a72bbec7 | 423 | #endif |
79365026 SJ |
424 | /* |
425 | * Initially, crash hotplug support for kexec_load was added | |
426 | * with the KEXEC_UPDATE_ELFCOREHDR flag. Later, this | |
427 | * functionality was expanded to accommodate multiple kexec | |
428 | * segment updates, leading to the introduction of the | |
429 | * KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag bit. Consequently, | |
430 | * when the kexec tool sends either of these flags, it indicates | |
431 | * that the required kexec segment (elfcorehdr) is excluded from | |
432 | * the SHA calculation. | |
433 | */ | |
434 | return (kexec_flags & KEXEC_UPDATE_ELFCOREHDR || | |
435 | kexec_flags & KEXEC_CRASH_HOTPLUG_SUPPORT); | |
436 | } | |
a72bbec7 ED |
437 | |
438 | unsigned int arch_crash_get_elfcorehdr_size(void) | |
439 | { | |
440 | unsigned int sz; | |
441 | ||
442 | /* kernel_map, VMCOREINFO and maximum CPUs */ | |
443 | sz = 2 + CONFIG_NR_CPUS_DEFAULT; | |
444 | if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG)) | |
445 | sz += CONFIG_CRASH_MAX_MEMORY_RANGES; | |
446 | sz *= sizeof(Elf64_Phdr); | |
447 | return sz; | |
448 | } | |
449 | ||
ea53ad9c ED |
450 | /** |
451 | * arch_crash_handle_hotplug_event() - Handle hotplug elfcorehdr changes | |
452 | * @image: a pointer to kexec_crash_image | |
11800571 SJ |
453 | * @arg: struct memory_notify handler for memory hotplug case and |
454 | * NULL for CPU hotplug case. | |
ea53ad9c ED |
455 | * |
456 | * Prepare the new elfcorehdr and replace the existing elfcorehdr. | |
457 | */ | |
11800571 | 458 | void arch_crash_handle_hotplug_event(struct kimage *image, void *arg) |
ea53ad9c ED |
459 | { |
460 | void *elfbuf = NULL, *old_elfcorehdr; | |
461 | unsigned long nr_mem_ranges; | |
462 | unsigned long mem, memsz; | |
463 | unsigned long elfsz = 0; | |
464 | ||
543cd4c5 ED |
465 | /* |
466 | * As crash_prepare_elf64_headers() has already described all | |
467 | * possible CPUs, there is no need to update the elfcorehdr | |
468 | * for additional CPU changes. | |
469 | */ | |
470 | if ((image->file_mode || image->elfcorehdr_updated) && | |
471 | ((image->hp_action == KEXEC_CRASH_HP_ADD_CPU) || | |
472 | (image->hp_action == KEXEC_CRASH_HP_REMOVE_CPU))) | |
473 | return; | |
474 | ||
ea53ad9c ED |
475 | /* |
476 | * Create the new elfcorehdr reflecting the changes to CPU and/or | |
477 | * memory resources. | |
478 | */ | |
83d4a42a | 479 | if (prepare_elf_headers(&elfbuf, &elfsz, &nr_mem_ranges)) { |
ea53ad9c ED |
480 | pr_err("unable to create new elfcorehdr"); |
481 | goto out; | |
482 | } | |
483 | ||
484 | /* | |
485 | * Obtain address and size of the elfcorehdr segment, and | |
486 | * check it against the new elfcorehdr buffer. | |
487 | */ | |
488 | mem = image->segment[image->elfcorehdr_index].mem; | |
489 | memsz = image->segment[image->elfcorehdr_index].memsz; | |
490 | if (elfsz > memsz) { | |
491 | pr_err("update elfcorehdr elfsz %lu > memsz %lu", | |
492 | elfsz, memsz); | |
493 | goto out; | |
494 | } | |
495 | ||
496 | /* | |
497 | * Copy new elfcorehdr over the old elfcorehdr at destination. | |
498 | */ | |
499 | old_elfcorehdr = kmap_local_page(pfn_to_page(mem >> PAGE_SHIFT)); | |
500 | if (!old_elfcorehdr) { | |
501 | pr_err("mapping elfcorehdr segment failed\n"); | |
502 | goto out; | |
503 | } | |
504 | ||
505 | /* | |
506 | * Temporarily invalidate the crash image while the | |
507 | * elfcorehdr is updated. | |
508 | */ | |
509 | xchg(&kexec_crash_image, NULL); | |
510 | memcpy_flushcache(old_elfcorehdr, elfbuf, elfsz); | |
511 | xchg(&kexec_crash_image, image); | |
512 | kunmap_local(old_elfcorehdr); | |
513 | pr_debug("updated elfcorehdr\n"); | |
514 | ||
515 | out: | |
516 | vfree(elfbuf); | |
517 | } | |
518 | #endif |