---

yaml
---
r: 71118
b: refs/heads/master
c: d158cbd
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d307c4a8e826c44f9633bd3f7e60d0491e7d885a
+refs/heads/master: d158cbdf39ffaec9dd5299fdfdfdd2c7897a71dc

trunk/arch/x86/kernel/suspend_64.c

@@ -150,8 +150,16 @@ void fix_processor_context(void)
 /* Defined in arch/x86_64/kernel/suspend_asm.S */
 extern int restore_image(void);
 
+/*
+ * Address to jump to in the last phase of restore in order to get to the image
+ * kernel's text (this value is passed in the image header).
+ */
+unsigned long restore_jump_address;
+
 pgd_t *temp_level4_pgt;
 
+void *relocated_restore_code;
+
 static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end)
 {
 	long i, j;
@@ -175,7 +183,7 @@ static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long en
 
 			if (paddr >= end)
 				break;
-			pe = _PAGE_NX | _PAGE_PSE | _KERNPG_TABLE | paddr;
+			pe = __PAGE_KERNEL_LARGE_EXEC | paddr;
 			pe &= __supported_pte_mask;
 			set_pmd(pmd, __pmd(pe));
 		}
@@ -222,6 +230,13 @@ int swsusp_arch_resume(void)
 	/* We have got enough memory and from now on we cannot recover */
 	if ((error = set_up_temporary_mappings()))
 		return error;
+
+	relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC);
+	if (!relocated_restore_code)
+		return -ENOMEM;
+	memcpy(relocated_restore_code, &core_restore_code,
+	       &restore_registers - &core_restore_code);
+
 	restore_image();
 	return 0;
 }
@@ -236,4 +251,41 @@ int pfn_is_nosave(unsigned long pfn)
 	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
 	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
 }
+
+struct restore_data_record {
+	unsigned long jump_address;
+	unsigned long control;
+};
+
+#define RESTORE_MAGIC	0x0123456789ABCDEFUL
+
+/**
+ *	arch_hibernation_header_save - populate the architecture specific part
+ *		of a hibernation image header
+ *	@addr: address to save the data at
+ */
+int arch_hibernation_header_save(void *addr, unsigned int max_size)
+{
+	struct restore_data_record *rdr = addr;
+
+	if (max_size < sizeof(struct restore_data_record))
+		return -EOVERFLOW;
+	rdr->jump_address = restore_jump_address;
+	rdr->control = (restore_jump_address ^ RESTORE_MAGIC);
+	return 0;
+}
+
+/**
+ *	arch_hibernation_header_restore - read the architecture specific data
+ *		from the hibernation image header
+ *	@addr: address to read the data from
+ */
+int arch_hibernation_header_restore(void *addr)
+{
+	struct restore_data_record *rdr = addr;
+
+	restore_jump_address = rdr->jump_address;
+	return (rdr->control == (restore_jump_address ^ RESTORE_MAGIC)) ?
+			0 : -EINVAL;
+}
 #endif /* CONFIG_HIBERNATION */

trunk/arch/x86/kernel/suspend_asm_64.S

@@ -2,8 +2,8 @@
  *
  * Distribute under GPLv2.
  *
- * swsusp_arch_resume may not use any stack, nor any variable that is
- * not "NoSave" during copying pages:
+ * swsusp_arch_resume must not use any stack or any nonlocal variables while
+ * copying pages:
  *
  * Its rewriting one kernel image with another. What is stack in "old"
  * image could very well be data page in "new" image, and overwriting
@@ -36,6 +36,10 @@ ENTRY(swsusp_arch_suspend)
 	movq %r15, saved_context_r15(%rip)
 	pushfq ; popq saved_context_eflags(%rip)
 
+	/* save the address of restore_registers */
+	movq	$restore_registers, %rax
+	movq	%rax, restore_jump_address(%rip)
+
 	call swsusp_save
 	ret
 
@@ -54,22 +58,45 @@ ENTRY(restore_image)
 	movq	%rcx, %cr3;
 	movq	%rax, %cr4;  # turn PGE back on
 
+	/* prepare to jump to the image kernel */
+	movq	restore_jump_address(%rip), %rax
+
+	/* prepare to copy image data to their original locations */
 	movq	restore_pblist(%rip), %rdx
+	movq	relocated_restore_code(%rip), %rcx
+	jmpq	*%rcx
+
+	/* code below has been relocated to a safe page */
+ENTRY(core_restore_code)
 loop:
 	testq	%rdx, %rdx
 	jz	done
 
 	/* get addresses from the pbe and copy the page */
 	movq	pbe_address(%rdx), %rsi
 	movq	pbe_orig_address(%rdx), %rdi
-	movq	$512, %rcx
+	movq	$(PAGE_SIZE >> 3), %rcx
 	rep
 	movsq
 
 	/* progress to the next pbe */
 	movq	pbe_next(%rdx), %rdx
 	jmp	loop
 done:
+	/* jump to the restore_registers address from the image header */
+	jmpq	*%rax
+	/*
+	 * NOTE: This assumes that the boot kernel's text mapping covers the
+	 * image kernel's page containing restore_registers and the address of
+	 * this page is the same as in the image kernel's text mapping (it
+	 * should always be true, because the text mapping is linear, starting
+	 * from 0, and is supposed to cover the entire kernel text for every
+	 * kernel).
+	 *
+	 * code below belongs to the image kernel
+	 */
+
+ENTRY(restore_registers)
 	/* go back to the original page tables */
 	movq    $(init_level4_pgt - __START_KERNEL_map), %rax
 	addq    phys_base(%rip), %rax
@@ -84,12 +111,9 @@ done:
 	movq	%rcx, %cr3
 	movq	%rax, %cr4;  # turn PGE back on
 
-	movl	$24, %eax
-	movl	%eax, %ds
-
 	movq saved_context_esp(%rip), %rsp
 	movq saved_context_ebp(%rip), %rbp
-	/* Don't restore %rax, it must be 0 anyway */
+	/* restore GPRs (we don't restore %rax, it must be 0 anyway) */
 	movq saved_context_ebx(%rip), %rbx
 	movq saved_context_ecx(%rip), %rcx
 	movq saved_context_edx(%rip), %rdx
@@ -107,4 +131,7 @@ done:
 
 	xorq	%rax, %rax
 
+	/* tell the hibernation core that we've just restored the memory */
+	movq	%rax, in_suspend(%rip)
+
 	ret

trunk/arch/x86_64/Kconfig

@@ -716,6 +716,11 @@ menu "Power management options"
 
 source kernel/power/Kconfig
 
+config ARCH_HIBERNATION_HEADER
+	bool
+	depends on HIBERNATION
+	default y
+
 source "drivers/acpi/Kconfig"
 
 source "arch/x86/kernel/cpufreq/Kconfig"

trunk/include/asm-x86/suspend_64.h

@@ -53,3 +53,5 @@ extern unsigned long saved_rdi;
 
 /* routines for saving/restoring kernel state */
 extern int acpi_save_state_mem(void);
+extern char core_restore_code;
+extern char restore_registers;