x86/power/64: Fix kernel text mapping corruption during image restoration

[cascardo/linux.git] / arch / x86 / power / hibernate_asm_64.S

diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S
index 4400a43..3177c2b 100644 (file)
--- a/arch/x86/power/hibernate_asm_64.S
+++ b/arch/x86/power/hibernate_asm_64.S
@@ -44,9 +44,6 @@ ENTRY(swsusp_arch_suspend)
        pushfq
        popq    pt_regs_flags(%rax)
 
-       /* 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)
@@ -57,31 +54,34 @@ ENTRY(swsusp_arch_suspend)
 ENDPROC(swsusp_arch_suspend)
 
 ENTRY(restore_image)
-       /* switch to temporary page tables */
-       movq    $__PAGE_OFFSET, %rdx
-       movq    temp_level4_pgt(%rip), %rax
-       subq    %rdx, %rax
-       movq    %rax, %cr3
-       /* Flush TLB */
-       movq    mmu_cr4_features(%rip), %rax
-       movq    %rax, %rdx
-       andq    $~(X86_CR4_PGE), %rdx
-       movq    %rdx, %cr4;  # turn off PGE
-       movq    %cr3, %rcx;  # flush TLB
-       movq    %rcx, %cr3;
-       movq    %rax, %cr4;  # turn PGE back on
-
        /* prepare to jump to the image kernel */
-       movq    restore_jump_address(%rip), %rax
-       movq    restore_cr3(%rip), %rbx
+       movq    restore_jump_address(%rip), %r8
+       movq    restore_cr3(%rip), %r9
+
+       /* prepare to switch to temporary page tables */
+       movq    temp_level4_pgt(%rip), %rax
+       movq    mmu_cr4_features(%rip), %rbx
 
        /* prepare to copy image data to their original locations */
        movq    restore_pblist(%rip), %rdx
+
+       /* jump to relocated restore code */
        movq    relocated_restore_code(%rip), %rcx
        jmpq    *%rcx
 
        /* code below has been relocated to a safe page */
 ENTRY(core_restore_code)
+       /* switch to temporary page tables */
+       movq    $__PAGE_OFFSET, %rcx
+       subq    %rcx, %rax
+       movq    %rax, %cr3
+       /* flush TLB */
+       movq    %rbx, %rcx
+       andq    $~(X86_CR4_PGE), %rcx
+       movq    %rcx, %cr4;  # turn off PGE
+       movq    %cr3, %rcx;  # flush TLB
+       movq    %rcx, %cr3;
+       movq    %rbx, %cr4;  # turn PGE back on
 .Lloop:
        testq   %rdx, %rdx
        jz      .Ldone
@@ -96,24 +96,17 @@ ENTRY(core_restore_code)
        /* progress to the next pbe */
        movq    pbe_next(%rdx), %rdx
        jmp     .Lloop
+
 .Ldone:
        /* 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
-        */
+       jmpq    *%r8
 
+        /* code below belongs to the image kernel */
+       .align PAGE_SIZE
 ENTRY(restore_registers)
        FRAME_BEGIN
        /* go back to the original page tables */
-       movq    %rbx, %cr3
+       movq    %r9, %cr3
 
        /* Flush TLB, including "global" things (vmalloc) */
        movq    mmu_cr4_features(%rip), %rax