From: Rafael J. Wysocki 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 Acked-by: Pavel Machek Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/x86_64/kernel/suspend.c | 16 ++++++++++++---- arch/x86_64/kernel/suspend_asm.S | 8 +++++--- 2 files changed, 17 insertions(+), 7 deletions(-) diff -puN arch/x86_64/kernel/suspend.c~hibernation-pass-cr3-in-the-image-header-on-x86_64-rev-2 arch/x86_64/kernel/suspend.c --- a/arch/x86_64/kernel/suspend.c~hibernation-pass-cr3-in-the-image-header-on-x86_64-rev-2 +++ a/arch/x86_64/kernel/suspend.c @@ -151,6 +151,12 @@ extern int restore_image(void); */ 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; @@ -249,7 +255,8 @@ int pfn_is_nosave(unsigned long pfn) struct restore_data_record { unsigned long jump_address; - unsigned long control; + unsigned long cr3; + unsigned long magic; }; #define RESTORE_MAGIC 0x0123456789ABCDEFUL @@ -266,7 +273,8 @@ int arch_hibernation_header_save(void *a 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; } @@ -280,7 +288,7 @@ int arch_hibernation_header_restore(void 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 -puN arch/x86_64/kernel/suspend_asm.S~hibernation-pass-cr3-in-the-image-header-on-x86_64-rev-2 arch/x86_64/kernel/suspend_asm.S --- a/arch/x86_64/kernel/suspend_asm.S~hibernation-pass-cr3-in-the-image-header-on-x86_64-rev-2 +++ a/arch/x86_64/kernel/suspend_asm.S @@ -39,6 +39,9 @@ ENTRY(swsusp_arch_suspend) /* 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 @@ ENTRY(restore_image) /* 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 @@ done: 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 _