diff options
Diffstat (limited to 'kernel/kexec_core.c')
| -rw-r--r-- | kernel/kexec_core.c | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index ae1a3ba24df5..1ae7c41c33c1 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -38,6 +38,7 @@ #include <linux/syscore_ops.h> #include <linux/compiler.h> #include <linux/hugetlb.h> +#include <linux/frame.h> #include <asm/page.h> #include <asm/sections.h> @@ -481,6 +482,40 @@ struct page *kimage_alloc_control_pages(struct kimage *image, 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) @@ -568,6 +603,11 @@ void kimage_free(struct kimage *image) if (!image) return; + if (image->vmcoreinfo_data_copy) { + crash_update_vmcoreinfo_safecopy(NULL); + vunmap(image->vmcoreinfo_data_copy); + } + kimage_free_extra_pages(image); for_each_kimage_entry(image, ptr, entry) { if (entry & IND_INDIRECTION) { @@ -874,7 +914,7 @@ int kexec_load_disabled; * only when panic_cpu holds the current CPU number; this is the only CPU * which processes crash_kexec routines. */ -void __crash_kexec(struct pt_regs *regs) +void __noclone __crash_kexec(struct pt_regs *regs) { /* Take the kexec_mutex here to prevent sys_kexec_load * running on one cpu from replacing the crash kernel @@ -896,6 +936,7 @@ void __crash_kexec(struct pt_regs *regs) mutex_unlock(&kexec_mutex); } } +STACK_FRAME_NON_STANDARD(__crash_kexec); void crash_kexec(struct pt_regs *regs) { |