1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) Linaro.
6 * Copyright (C) Huawei Futurewei Technologies.
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/kernel.h>
12 #include <linux/kexec.h>
13 #include <linux/page-flags.h>
14 #include <linux/set_memory.h>
15 #include <linux/smp.h>
17 #include <asm/cacheflush.h>
18 #include <asm/cpu_ops.h>
19 #include <asm/daifflags.h>
20 #include <asm/memory.h>
22 #include <asm/mmu_context.h>
24 #include <asm/sections.h>
25 #include <asm/trans_pgd.h>
28 * kexec_image_info - For debugging output.
30 #define kexec_image_info(_i) _kexec_image_info(__func__, __LINE__, _i)
31 static void _kexec_image_info(const char *func, int line,
32 const struct kimage *kimage)
36 pr_debug("%s:%d:\n", func, line);
37 pr_debug(" kexec kimage info:\n");
38 pr_debug(" type: %d\n", kimage->type);
39 pr_debug(" start: %lx\n", kimage->start);
40 pr_debug(" head: %lx\n", kimage->head);
41 pr_debug(" nr_segments: %lu\n", kimage->nr_segments);
42 pr_debug(" dtb_mem: %pa\n", &kimage->arch.dtb_mem);
43 pr_debug(" kern_reloc: %pa\n", &kimage->arch.kern_reloc);
44 pr_debug(" el2_vectors: %pa\n", &kimage->arch.el2_vectors);
46 for (i = 0; i < kimage->nr_segments; i++) {
47 pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
49 kimage->segment[i].mem,
50 kimage->segment[i].mem + kimage->segment[i].memsz,
51 kimage->segment[i].memsz,
52 kimage->segment[i].memsz / PAGE_SIZE);
56 void machine_kexec_cleanup(struct kimage *kimage)
58 /* Empty routine needed to avoid build errors. */
62 * machine_kexec_prepare - Prepare for a kexec reboot.
64 * Called from the core kexec code when a kernel image is loaded.
65 * Forbid loading a kexec kernel if we have no way of hotplugging cpus or cpus
66 * are stuck in the kernel. This avoids a panic once we hit machine_kexec().
68 int machine_kexec_prepare(struct kimage *kimage)
70 if (kimage->type != KEXEC_TYPE_CRASH && cpus_are_stuck_in_kernel()) {
71 pr_err("Can't kexec: CPUs are stuck in the kernel.\n");
79 * kexec_segment_flush - Helper to flush the kimage segments to PoC.
81 static void kexec_segment_flush(const struct kimage *kimage)
85 pr_debug("%s:\n", __func__);
87 for (i = 0; i < kimage->nr_segments; i++) {
88 pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",
90 kimage->segment[i].mem,
91 kimage->segment[i].mem + kimage->segment[i].memsz,
92 kimage->segment[i].memsz,
93 kimage->segment[i].memsz / PAGE_SIZE);
95 dcache_clean_inval_poc(
96 (unsigned long)phys_to_virt(kimage->segment[i].mem),
97 (unsigned long)phys_to_virt(kimage->segment[i].mem) +
98 kimage->segment[i].memsz);
102 /* Allocates pages for kexec page table */
103 static void *kexec_page_alloc(void *arg)
105 struct kimage *kimage = (struct kimage *)arg;
106 struct page *page = kimage_alloc_control_pages(kimage, 0);
112 vaddr = page_address(page);
113 memset(vaddr, 0, PAGE_SIZE);
118 int machine_kexec_post_load(struct kimage *kimage)
122 void *reloc_code = page_to_virt(kimage->control_code_page);
124 struct trans_pgd_info info = {
125 .trans_alloc_page = kexec_page_alloc,
126 .trans_alloc_arg = kimage,
129 /* If in place, relocation is not used, only flush next kernel */
130 if (kimage->head & IND_DONE) {
131 kexec_segment_flush(kimage);
132 kexec_image_info(kimage);
136 kimage->arch.el2_vectors = 0;
138 rc = trans_pgd_copy_el2_vectors(&info,
139 &kimage->arch.el2_vectors);
144 /* Create a copy of the linear map */
145 trans_pgd = kexec_page_alloc(kimage);
148 rc = trans_pgd_create_copy(&info, &trans_pgd, PAGE_OFFSET, PAGE_END);
151 kimage->arch.ttbr1 = __pa(trans_pgd);
152 kimage->arch.zero_page = __pa_symbol(empty_zero_page);
154 reloc_size = __relocate_new_kernel_end - __relocate_new_kernel_start;
155 memcpy(reloc_code, __relocate_new_kernel_start, reloc_size);
156 kimage->arch.kern_reloc = __pa(reloc_code);
157 rc = trans_pgd_idmap_page(&info, &kimage->arch.ttbr0,
158 &kimage->arch.t0sz, reloc_code);
161 kimage->arch.phys_offset = virt_to_phys(kimage) - (long)kimage;
163 /* Flush the reloc_code in preparation for its execution. */
164 dcache_clean_inval_poc((unsigned long)reloc_code,
165 (unsigned long)reloc_code + reloc_size);
166 icache_inval_pou((uintptr_t)reloc_code,
167 (uintptr_t)reloc_code + reloc_size);
168 kexec_image_info(kimage);
174 * machine_kexec - Do the kexec reboot.
176 * Called from the core kexec code for a sys_reboot with LINUX_REBOOT_CMD_KEXEC.
178 void machine_kexec(struct kimage *kimage)
180 bool in_kexec_crash = (kimage == kexec_crash_image);
181 bool stuck_cpus = cpus_are_stuck_in_kernel();
184 * New cpus may have become stuck_in_kernel after we loaded the image.
186 BUG_ON(!in_kexec_crash && (stuck_cpus || (num_online_cpus() > 1)));
187 WARN(in_kexec_crash && (stuck_cpus || smp_crash_stop_failed()),
188 "Some CPUs may be stale, kdump will be unreliable.\n");
195 * Both restart and kernel_reloc will shutdown the MMU, disable data
196 * caches. However, restart will start new kernel or purgatory directly,
197 * kernel_reloc contains the body of arm64_relocate_new_kernel
198 * In kexec case, kimage->start points to purgatory assuming that
199 * kernel entry and dtb address are embedded in purgatory by
200 * userspace (kexec-tools).
201 * In kexec_file case, the kernel starts directly without purgatory.
203 if (kimage->head & IND_DONE) {
204 typeof(cpu_soft_restart) *restart;
207 restart = (void *)__pa_symbol(function_nocfi(cpu_soft_restart));
208 restart(is_hyp_nvhe(), kimage->start, kimage->arch.dtb_mem,
211 void (*kernel_reloc)(struct kimage *kimage);
214 __hyp_set_vectors(kimage->arch.el2_vectors);
215 cpu_install_ttbr0(kimage->arch.ttbr0, kimage->arch.t0sz);
216 kernel_reloc = (void *)kimage->arch.kern_reloc;
217 kernel_reloc(kimage);
220 BUG(); /* Should never get here. */
223 static void machine_kexec_mask_interrupts(void)
226 struct irq_desc *desc;
228 for_each_irq_desc(i, desc) {
229 struct irq_chip *chip;
232 chip = irq_desc_get_chip(desc);
237 * First try to remove the active state. If this
238 * fails, try to EOI the interrupt.
240 ret = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
242 if (ret && irqd_irq_inprogress(&desc->irq_data) &&
244 chip->irq_eoi(&desc->irq_data);
247 chip->irq_mask(&desc->irq_data);
249 if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
250 chip->irq_disable(&desc->irq_data);
255 * machine_crash_shutdown - shutdown non-crashing cpus and save registers
257 void machine_crash_shutdown(struct pt_regs *regs)
261 /* shutdown non-crashing cpus */
262 crash_smp_send_stop();
264 /* for crashing cpu */
265 crash_save_cpu(regs, smp_processor_id());
266 machine_kexec_mask_interrupts();
268 pr_info("Starting crashdump kernel...\n");
271 void arch_kexec_protect_crashkres(void)
275 for (i = 0; i < kexec_crash_image->nr_segments; i++)
277 __phys_to_virt(kexec_crash_image->segment[i].mem),
278 kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 0);
281 void arch_kexec_unprotect_crashkres(void)
285 for (i = 0; i < kexec_crash_image->nr_segments; i++)
287 __phys_to_virt(kexec_crash_image->segment[i].mem),
288 kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 1);
291 #ifdef CONFIG_HIBERNATION
293 * To preserve the crash dump kernel image, the relevant memory segments
294 * should be mapped again around the hibernation.
296 void crash_prepare_suspend(void)
298 if (kexec_crash_image)
299 arch_kexec_unprotect_crashkres();
302 void crash_post_resume(void)
304 if (kexec_crash_image)
305 arch_kexec_protect_crashkres();
311 * Return true only if a page is part of reserved memory for crash dump kernel,
312 * but does not hold any data of loaded kernel image.
314 * Note that all the pages in crash dump kernel memory have been initially
315 * marked as Reserved as memory was allocated via memblock_reserve().
317 * In hibernation, the pages which are Reserved and yet "nosave" are excluded
318 * from the hibernation iamge. crash_is_nosave() does thich check for crash
319 * dump kernel and will reduce the total size of hibernation image.
322 bool crash_is_nosave(unsigned long pfn)
330 /* in reserved memory? */
331 addr = __pfn_to_phys(pfn);
332 if ((addr < crashk_res.start) || (crashk_res.end < addr))
335 if (!kexec_crash_image)
338 /* not part of loaded kernel image? */
339 for (i = 0; i < kexec_crash_image->nr_segments; i++)
340 if (addr >= kexec_crash_image->segment[i].mem &&
341 addr < (kexec_crash_image->segment[i].mem +
342 kexec_crash_image->segment[i].memsz))
348 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
353 for (addr = begin; addr < end; addr += PAGE_SIZE) {
354 page = phys_to_page(addr);
355 free_reserved_page(page);
358 #endif /* CONFIG_HIBERNATION */