Hibernation: Pass CR3 in the image header on x86_64
Since we already pass the address of restore_registers() in the image header,
we can also pass the value of the CR3 register from before the hibernation in
the same way. This will allow us to avoid using init_level4_pgt page tables
during the restore.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/x86/kernel/suspend_64.c b/arch/x86/kernel/suspend_64.c
index 01fbfb0..da10eef 100644
--- a/arch/x86/kernel/suspend_64.c
+++ b/arch/x86/kernel/suspend_64.c
@@ -156,6 +156,12 @@
*/
unsigned long restore_jump_address;
+/*
+ * Value of the cr3 register from before the hibernation (this value is passed
+ * in the image header).
+ */
+unsigned long restore_cr3;
+
pgd_t *temp_level4_pgt;
void *relocated_restore_code;
@@ -254,7 +260,8 @@
struct restore_data_record {
unsigned long jump_address;
- unsigned long control;
+ unsigned long cr3;
+ unsigned long magic;
};
#define RESTORE_MAGIC 0x0123456789ABCDEFUL
@@ -271,7 +278,8 @@
if (max_size < sizeof(struct restore_data_record))
return -EOVERFLOW;
rdr->jump_address = restore_jump_address;
- rdr->control = (restore_jump_address ^ RESTORE_MAGIC);
+ rdr->cr3 = restore_cr3;
+ rdr->magic = RESTORE_MAGIC;
return 0;
}
@@ -285,7 +293,7 @@
struct restore_data_record *rdr = addr;
restore_jump_address = rdr->jump_address;
- return (rdr->control == (restore_jump_address ^ RESTORE_MAGIC)) ?
- 0 : -EINVAL;
+ restore_cr3 = rdr->cr3;
+ return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL;
}
#endif /* CONFIG_HIBERNATION */
diff --git a/arch/x86/kernel/suspend_asm_64.S b/arch/x86/kernel/suspend_asm_64.S
index 40a209e..48344b6 100644
--- a/arch/x86/kernel/suspend_asm_64.S
+++ b/arch/x86/kernel/suspend_asm_64.S
@@ -39,6 +39,9 @@
/* save the address of restore_registers */
movq $restore_registers, %rax
movq %rax, restore_jump_address(%rip)
+ /* save cr3 */
+ movq %cr3, %rax
+ movq %rax, restore_cr3(%rip)
call swsusp_save
ret
@@ -60,6 +63,7 @@
/* prepare to jump to the image kernel */
movq restore_jump_address(%rip), %rax
+ movq restore_cr3(%rip), %rbx
/* prepare to copy image data to their original locations */
movq restore_pblist(%rip), %rdx
@@ -98,9 +102,7 @@
ENTRY(restore_registers)
/* go back to the original page tables */
- movq $(init_level4_pgt - __START_KERNEL_map), %rax
- addq phys_base(%rip), %rax
- movq %rax, %cr3
+ movq %rbx, %cr3
/* Flush TLB, including "global" things (vmalloc) */
movq mmu_cr4_features(%rip), %rax