bool kexec_file_dbg_print;
-int kexec_should_crash(struct task_struct *p)
-{
- /*
- * If crash_kexec_post_notifiers is enabled, don't run
- * crash_kexec() here yet, which must be run after panic
- * notifiers in panic().
- */
- if (crash_kexec_post_notifiers)
- return 0;
- /*
- * There are 4 panic() calls in make_task_dead() path, each of which
- * corresponds to each of these 4 conditions.
- */
- if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
- return 1;
- return 0;
-}
-
-int kexec_crash_loaded(void)
-{
- return !!kexec_crash_image;
-}
-EXPORT_SYMBOL_GPL(kexec_crash_loaded);
-
/*
* When kexec transitions to the new kernel there is a one-to-one
* mapping between physical and virtual addresses. On processors
if (total_pages > nr_pages / 2)
return -EINVAL;
+#ifdef CONFIG_CRASH_DUMP
/*
* Verify we have good destination addresses. Normally
* the caller is responsible for making certain we don't
return -EADDRNOTAVAIL;
}
}
+#endif
return 0;
}
return pages;
}
+#ifdef CONFIG_CRASH_DUMP
static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
unsigned int order)
{
return pages;
}
+#endif
struct page *kimage_alloc_control_pages(struct kimage *image,
case KEXEC_TYPE_DEFAULT:
pages = kimage_alloc_normal_control_pages(image, order);
break;
+#ifdef CONFIG_CRASH_DUMP
case KEXEC_TYPE_CRASH:
pages = kimage_alloc_crash_control_pages(image, order);
break;
+#endif
}
return pages;
}
-int kimage_crash_copy_vmcoreinfo(struct kimage *image)
-{
- struct page *vmcoreinfo_page;
- void *safecopy;
-
- if (image->type != KEXEC_TYPE_CRASH)
- return 0;
-
- /*
- * For kdump, allocate one vmcoreinfo safe copy from the
- * crash memory. as we have arch_kexec_protect_crashkres()
- * after kexec syscall, we naturally protect it from write
- * (even read) access under kernel direct mapping. But on
- * the other hand, we still need to operate it when crash
- * happens to generate vmcoreinfo note, hereby we rely on
- * vmap for this purpose.
- */
- vmcoreinfo_page = kimage_alloc_control_pages(image, 0);
- if (!vmcoreinfo_page) {
- pr_warn("Could not allocate vmcoreinfo buffer\n");
- return -ENOMEM;
- }
- safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL);
- if (!safecopy) {
- pr_warn("Could not vmap vmcoreinfo buffer\n");
- return -ENOMEM;
- }
-
- image->vmcoreinfo_data_copy = safecopy;
- crash_update_vmcoreinfo_safecopy(safecopy);
-
- return 0;
-}
-
static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
{
if (*image->entry != 0)
if (!image)
return;
+#ifdef CONFIG_CRASH_DUMP
if (image->vmcoreinfo_data_copy) {
crash_update_vmcoreinfo_safecopy(NULL);
vunmap(image->vmcoreinfo_data_copy);
}
+#endif
kimage_free_extra_pages(image);
for_each_kimage_entry(image, ptr, entry) {
PAGE_SIZE - (maddr & ~PAGE_MASK));
uchunk = min(ubytes, mchunk);
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
+ if (uchunk) {
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ ubytes -= uchunk;
+ if (image->file_mode)
+ kbuf += uchunk;
+ else
+ buf += uchunk;
+ }
kunmap_local(ptr);
if (result) {
result = -EFAULT;
goto out;
}
- ubytes -= uchunk;
maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
mbytes -= mchunk;
cond_resched();
return result;
}
+#ifdef CONFIG_CRASH_DUMP
static int kimage_load_crash_segment(struct kimage *image,
struct kexec_segment *segment)
{
memset(ptr + uchunk, 0, mchunk - uchunk);
}
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
+ if (uchunk) {
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ ubytes -= uchunk;
+ if (image->file_mode)
+ kbuf += uchunk;
+ else
+ buf += uchunk;
+ }
kexec_flush_icache_page(page);
kunmap_local(ptr);
arch_kexec_pre_free_pages(page_address(page), 1);
result = -EFAULT;
goto out;
}
- ubytes -= uchunk;
maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
mbytes -= mchunk;
cond_resched();
out:
return result;
}
+#endif
int kimage_load_segment(struct kimage *image,
struct kexec_segment *segment)
case KEXEC_TYPE_DEFAULT:
result = kimage_load_normal_segment(image, segment);
break;
+#ifdef CONFIG_CRASH_DUMP
case KEXEC_TYPE_CRASH:
result = kimage_load_crash_segment(image, segment);
break;
+#endif
}
return result;
return true;
}
-/*
- * No panic_cpu check version of crash_kexec(). This function is called
- * only when panic_cpu holds the current CPU number; this is the only CPU
- * which processes crash_kexec routines.
- */
-void __noclone __crash_kexec(struct pt_regs *regs)
-{
- /* Take the kexec_lock here to prevent sys_kexec_load
- * running on one cpu from replacing the crash kernel
- * we are using after a panic on a different cpu.
- *
- * If the crash kernel was not located in a fixed area
- * of memory the xchg(&kexec_crash_image) would be
- * sufficient. But since I reuse the memory...
- */
- if (kexec_trylock()) {
- if (kexec_crash_image) {
- struct pt_regs fixed_regs;
-
- crash_setup_regs(&fixed_regs, regs);
- crash_save_vmcoreinfo();
- machine_crash_shutdown(&fixed_regs);
- machine_kexec(kexec_crash_image);
- }
- kexec_unlock();
- }
-}
-STACK_FRAME_NON_STANDARD(__crash_kexec);
-
-__bpf_kfunc void crash_kexec(struct pt_regs *regs)
-{
- int old_cpu, this_cpu;
-
- /*
- * Only one CPU is allowed to execute the crash_kexec() code as with
- * panic(). Otherwise parallel calls of panic() and crash_kexec()
- * may stop each other. To exclude them, we use panic_cpu here too.
- */
- old_cpu = PANIC_CPU_INVALID;
- this_cpu = raw_smp_processor_id();
-
- if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) {
- /* This is the 1st CPU which comes here, so go ahead. */
- __crash_kexec(regs);
-
- /*
- * Reset panic_cpu to allow another panic()/crash_kexec()
- * call.
- */
- atomic_set(&panic_cpu, PANIC_CPU_INVALID);
- }
-}
-
-static inline resource_size_t crash_resource_size(const struct resource *res)
-{
- return !res->end ? 0 : resource_size(res);
-}
-
-ssize_t crash_get_memory_size(void)
-{
- ssize_t size = 0;
-
- if (!kexec_trylock())
- return -EBUSY;
-
- size += crash_resource_size(&crashk_res);
- size += crash_resource_size(&crashk_low_res);
-
- kexec_unlock();
- return size;
-}
-
-static int __crash_shrink_memory(struct resource *old_res,
- unsigned long new_size)
-{
- struct resource *ram_res;
-
- ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
- if (!ram_res)
- return -ENOMEM;
-
- ram_res->start = old_res->start + new_size;
- ram_res->end = old_res->end;
- ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
- ram_res->name = "System RAM";
-
- if (!new_size) {
- release_resource(old_res);
- old_res->start = 0;
- old_res->end = 0;
- } else {
- crashk_res.end = ram_res->start - 1;
- }
-
- crash_free_reserved_phys_range(ram_res->start, ram_res->end);
- insert_resource(&iomem_resource, ram_res);
-
- return 0;
-}
-
-int crash_shrink_memory(unsigned long new_size)
-{
- int ret = 0;
- unsigned long old_size, low_size;
-
- if (!kexec_trylock())
- return -EBUSY;
-
- if (kexec_crash_image) {
- ret = -ENOENT;
- goto unlock;
- }
-
- low_size = crash_resource_size(&crashk_low_res);
- old_size = crash_resource_size(&crashk_res) + low_size;
- new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
- if (new_size >= old_size) {
- ret = (new_size == old_size) ? 0 : -EINVAL;
- goto unlock;
- }
-
- /*
- * (low_size > new_size) implies that low_size is greater than zero.
- * This also means that if low_size is zero, the else branch is taken.
- *
- * If low_size is greater than 0, (low_size > new_size) indicates that
- * crashk_low_res also needs to be shrunken. Otherwise, only crashk_res
- * needs to be shrunken.
- */
- if (low_size > new_size) {
- ret = __crash_shrink_memory(&crashk_res, 0);
- if (ret)
- goto unlock;
-
- ret = __crash_shrink_memory(&crashk_low_res, new_size);
- } else {
- ret = __crash_shrink_memory(&crashk_res, new_size - low_size);
- }
-
- /* Swap crashk_res and crashk_low_res if needed */
- if (!crashk_res.end && crashk_low_res.end) {
- crashk_res.start = crashk_low_res.start;
- crashk_res.end = crashk_low_res.end;
- release_resource(&crashk_low_res);
- crashk_low_res.start = 0;
- crashk_low_res.end = 0;
- insert_resource(&iomem_resource, &crashk_res);
- }
-
-unlock:
- kexec_unlock();
- return ret;
-}
-
-void crash_save_cpu(struct pt_regs *regs, int cpu)
-{
- struct elf_prstatus prstatus;
- u32 *buf;
-
- if ((cpu < 0) || (cpu >= nr_cpu_ids))
- return;
-
- /* Using ELF notes here is opportunistic.
- * I need a well defined structure format
- * for the data I pass, and I need tags
- * on the data to indicate what information I have
- * squirrelled away. ELF notes happen to provide
- * all of that, so there is no need to invent something new.
- */
- buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
- if (!buf)
- return;
- memset(&prstatus, 0, sizeof(prstatus));
- prstatus.common.pr_pid = current->pid;
- elf_core_copy_regs(&prstatus.pr_reg, regs);
- buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
- &prstatus, sizeof(prstatus));
- final_note(buf);
-}
-
/*
* Move into place and start executing a preloaded standalone
* executable. If nothing was preloaded return an error.
projects / thirdparty / linux.git / blobdiff