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Diffstat (limited to 'arch/x86_64/kernel/machine_kexec.c')
-rw-r--r--arch/x86_64/kernel/machine_kexec.c99
1 files changed, 65 insertions, 34 deletions
diff --git a/arch/x86_64/kernel/machine_kexec.c b/arch/x86_64/kernel/machine_kexec.c
index 106076b370f..0497e3bd5bf 100644
--- a/arch/x86_64/kernel/machine_kexec.c
+++ b/arch/x86_64/kernel/machine_kexec.c
@@ -15,6 +15,15 @@
#include <asm/mmu_context.h>
#include <asm/io.h>
+#define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE)))
+static u64 kexec_pgd[512] PAGE_ALIGNED;
+static u64 kexec_pud0[512] PAGE_ALIGNED;
+static u64 kexec_pmd0[512] PAGE_ALIGNED;
+static u64 kexec_pte0[512] PAGE_ALIGNED;
+static u64 kexec_pud1[512] PAGE_ALIGNED;
+static u64 kexec_pmd1[512] PAGE_ALIGNED;
+static u64 kexec_pte1[512] PAGE_ALIGNED;
+
static void init_level2_page(pmd_t *level2p, unsigned long addr)
{
unsigned long end_addr;
@@ -144,32 +153,19 @@ static void load_segments(void)
);
}
-typedef NORET_TYPE void (*relocate_new_kernel_t)(unsigned long indirection_page,
- unsigned long control_code_buffer,
- unsigned long start_address,
- unsigned long pgtable) ATTRIB_NORET;
-
-extern const unsigned char relocate_new_kernel[];
-extern const unsigned long relocate_new_kernel_size;
-
int machine_kexec_prepare(struct kimage *image)
{
- unsigned long start_pgtable, control_code_buffer;
+ unsigned long start_pgtable;
int result;
/* Calculate the offsets */
start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT;
- control_code_buffer = start_pgtable + PAGE_SIZE;
/* Setup the identity mapped 64bit page table */
result = init_pgtable(image, start_pgtable);
if (result)
return result;
- /* Place the code in the reboot code buffer */
- memcpy(__va(control_code_buffer), relocate_new_kernel,
- relocate_new_kernel_size);
-
return 0;
}
@@ -184,28 +180,34 @@ void machine_kexec_cleanup(struct kimage *image)
*/
NORET_TYPE void machine_kexec(struct kimage *image)
{
- unsigned long page_list;
- unsigned long control_code_buffer;
- unsigned long start_pgtable;
- relocate_new_kernel_t rnk;
+ unsigned long page_list[PAGES_NR];
+ void *control_page;
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
- /* Calculate the offsets */
- page_list = image->head;
- start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT;
- control_code_buffer = start_pgtable + PAGE_SIZE;
-
- /* Set the low half of the page table to my identity mapped
- * page table for kexec. Leave the high half pointing at the
- * kernel pages. Don't bother to flush the global pages
- * as that will happen when I fully switch to my identity mapped
- * page table anyway.
- */
- memcpy(__va(read_cr3()), __va(start_pgtable), PAGE_SIZE/2);
- __flush_tlb();
-
+ control_page = page_address(image->control_code_page) + PAGE_SIZE;
+ memcpy(control_page, relocate_kernel, PAGE_SIZE);
+
+ page_list[PA_CONTROL_PAGE] = __pa(control_page);
+ page_list[VA_CONTROL_PAGE] = (unsigned long)relocate_kernel;
+ page_list[PA_PGD] = __pa(kexec_pgd);
+ page_list[VA_PGD] = (unsigned long)kexec_pgd;
+ page_list[PA_PUD_0] = __pa(kexec_pud0);
+ page_list[VA_PUD_0] = (unsigned long)kexec_pud0;
+ page_list[PA_PMD_0] = __pa(kexec_pmd0);
+ page_list[VA_PMD_0] = (unsigned long)kexec_pmd0;
+ page_list[PA_PTE_0] = __pa(kexec_pte0);
+ page_list[VA_PTE_0] = (unsigned long)kexec_pte0;
+ page_list[PA_PUD_1] = __pa(kexec_pud1);
+ page_list[VA_PUD_1] = (unsigned long)kexec_pud1;
+ page_list[PA_PMD_1] = __pa(kexec_pmd1);
+ page_list[VA_PMD_1] = (unsigned long)kexec_pmd1;
+ page_list[PA_PTE_1] = __pa(kexec_pte1);
+ page_list[VA_PTE_1] = (unsigned long)kexec_pte1;
+
+ page_list[PA_TABLE_PAGE] =
+ (unsigned long)__pa(page_address(image->control_code_page));
/* The segment registers are funny things, they have both a
* visible and an invisible part. Whenever the visible part is
@@ -222,7 +224,36 @@ NORET_TYPE void machine_kexec(struct kimage *image)
*/
set_gdt(phys_to_virt(0),0);
set_idt(phys_to_virt(0),0);
+
/* now call it */
- rnk = (relocate_new_kernel_t) control_code_buffer;
- (*rnk)(page_list, control_code_buffer, image->start, start_pgtable);
+ relocate_kernel((unsigned long)image->head, (unsigned long)page_list,
+ image->start);
}
+
+/* crashkernel=size@addr specifies the location to reserve for
+ * a crash kernel. By reserving this memory we guarantee
+ * that linux never set's it up as a DMA target.
+ * Useful for holding code to do something appropriate
+ * after a kernel panic.
+ */
+static int __init setup_crashkernel(char *arg)
+{
+ unsigned long size, base;
+ char *p;
+ if (!arg)
+ return -EINVAL;
+ size = memparse(arg, &p);
+ if (arg == p)
+ return -EINVAL;
+ if (*p == '@') {
+ base = memparse(p+1, &p);
+ /* FIXME: Do I want a sanity check to validate the
+ * memory range? Yes you do, but it's too early for
+ * e820 -AK */
+ crashk_res.start = base;
+ crashk_res.end = base + size - 1;
+ }
+ return 0;
+}
+early_param("crashkernel", setup_crashkernel);
+