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[PATCH] swsusp: clean assembly parts

This patch fixes register saving so that each register is only saved once,
and adds missing saving of %cr8 on x86-64.  Some reordering so that
save/restore is more logical/safer (segment registers should be restored
after gdt).

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Pavel Machek 20 years ago
parent
commit
8d783b3e02
3 changed files with 17 additions and 20 deletions
  1. 7 10
      arch/i386/power/cpu.c
  2. 9 9
      arch/x86_64/kernel/suspend.c
  3. 1 1
      include/asm-x86_64/suspend.h

+ 7 - 10
arch/i386/power/cpu.c

@@ -44,7 +44,6 @@ void __save_processor_state(struct saved_context *ctxt)
 	 */
 	asm volatile ("sgdt %0" : "=m" (ctxt->gdt_limit));
 	asm volatile ("sidt %0" : "=m" (ctxt->idt_limit));
-	asm volatile ("sldt %0" : "=m" (ctxt->ldt));
 	asm volatile ("str %0"  : "=m" (ctxt->tr));
 
 	/*
@@ -107,7 +106,6 @@ static void fix_processor_context(void)
 
 void __restore_processor_state(struct saved_context *ctxt)
 {
-
 	/*
 	 * control registers
 	 */
@@ -116,6 +114,13 @@ void __restore_processor_state(struct saved_context *ctxt)
 	asm volatile ("movl %0, %%cr2" :: "r" (ctxt->cr2));
 	asm volatile ("movl %0, %%cr0" :: "r" (ctxt->cr0));
 
+	/*
+	 * now restore the descriptor tables to their proper values
+	 * ltr is done i fix_processor_context().
+	 */
+	asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
+	asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
+
 	/*
 	 * segment registers
 	 */
@@ -124,14 +129,6 @@ void __restore_processor_state(struct saved_context *ctxt)
 	asm volatile ("movw %0, %%gs" :: "r" (ctxt->gs));
 	asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss));
 
-	/*
-	 * now restore the descriptor tables to their proper values
-	 * ltr is done i fix_processor_context().
-	 */
-	asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
-	asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
-	asm volatile ("lldt %0" :: "m" (ctxt->ldt));
-
 	/*
 	 * sysenter MSRs
 	 */

+ 9 - 9
arch/x86_64/kernel/suspend.c

@@ -44,7 +44,6 @@ void __save_processor_state(struct saved_context *ctxt)
 	 */
 	asm volatile ("sgdt %0" : "=m" (ctxt->gdt_limit));
 	asm volatile ("sidt %0" : "=m" (ctxt->idt_limit));
-	asm volatile ("sldt %0" : "=m" (ctxt->ldt));
 	asm volatile ("str %0"  : "=m" (ctxt->tr));
 
 	/* XMM0..XMM15 should be handled by kernel_fpu_begin(). */
@@ -69,6 +68,7 @@ void __save_processor_state(struct saved_context *ctxt)
 	asm volatile ("movq %%cr2, %0" : "=r" (ctxt->cr2));
 	asm volatile ("movq %%cr3, %0" : "=r" (ctxt->cr3));
 	asm volatile ("movq %%cr4, %0" : "=r" (ctxt->cr4));
+	asm volatile ("movq %%cr8, %0" : "=r" (ctxt->cr8));
 }
 
 void save_processor_state(void)
@@ -90,11 +90,19 @@ void __restore_processor_state(struct saved_context *ctxt)
 	/*
 	 * control registers
 	 */
+	asm volatile ("movq %0, %%cr8" :: "r" (ctxt->cr8));
 	asm volatile ("movq %0, %%cr4" :: "r" (ctxt->cr4));
 	asm volatile ("movq %0, %%cr3" :: "r" (ctxt->cr3));
 	asm volatile ("movq %0, %%cr2" :: "r" (ctxt->cr2));
 	asm volatile ("movq %0, %%cr0" :: "r" (ctxt->cr0));
 
+	/*
+	 * now restore the descriptor tables to their proper values
+	 * ltr is done i fix_processor_context().
+	 */
+	asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
+	asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
+
 	/*
 	 * segment registers
 	 */
@@ -108,14 +116,6 @@ void __restore_processor_state(struct saved_context *ctxt)
 	wrmsrl(MSR_GS_BASE, ctxt->gs_base);
 	wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
 
-	/*
-	 * now restore the descriptor tables to their proper values
-	 * ltr is done i fix_processor_context().
-	 */
-	asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
-	asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
-	asm volatile ("lldt %0" :: "m" (ctxt->ldt));
-
 	fix_processor_context();
 
 	do_fpu_end();

+ 1 - 1
include/asm-x86_64/suspend.h

@@ -16,7 +16,7 @@ arch_prepare_suspend(void)
 struct saved_context {
   	u16 ds, es, fs, gs, ss;
 	unsigned long gs_base, gs_kernel_base, fs_base;
-	unsigned long cr0, cr2, cr3, cr4;
+	unsigned long cr0, cr2, cr3, cr4, cr8;
 	u16 gdt_pad;
 	u16 gdt_limit;
 	unsigned long gdt_base;