/*
* descriptor tables
*/
-#ifdef CONFIG_X86_32
store_idt(&ctxt->idt);
-#else
-/* CONFIG_X86_64 */
- store_idt((struct desc_ptr *)&ctxt->idt_limit);
-#endif
+
/*
* We save it here, but restore it only in the hibernate case.
* For ACPI S3 resume, this is loaded via 'early_gdt_desc' in 64-bit
/*
* segment registers
*/
-#ifdef CONFIG_X86_32
- savesegment(es, ctxt->es);
- savesegment(fs, ctxt->fs);
+#ifdef CONFIG_X86_32_LAZY_GS
savesegment(gs, ctxt->gs);
- savesegment(ss, ctxt->ss);
-#else
-/* CONFIG_X86_64 */
- asm volatile ("movw %%ds, %0" : "=m" (ctxt->ds));
- asm volatile ("movw %%es, %0" : "=m" (ctxt->es));
- asm volatile ("movw %%fs, %0" : "=m" (ctxt->fs));
- asm volatile ("movw %%gs, %0" : "=m" (ctxt->gs));
- asm volatile ("movw %%ss, %0" : "=m" (ctxt->ss));
+#endif
+#ifdef CONFIG_X86_64
+ savesegment(gs, ctxt->gs);
+ savesegment(fs, ctxt->fs);
+ savesegment(ds, ctxt->ds);
+ savesegment(es, ctxt->es);
rdmsrl(MSR_FS_BASE, ctxt->fs_base);
- rdmsrl(MSR_GS_BASE, ctxt->gs_base);
- rdmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
+ rdmsrl(MSR_GS_BASE, ctxt->kernelmode_gs_base);
+ rdmsrl(MSR_KERNEL_GS_BASE, ctxt->usermode_gs_base);
mtrr_save_fixed_ranges(NULL);
rdmsrl(MSR_EFER, ctxt->efer);
static void fix_processor_context(void)
{
int cpu = smp_processor_id();
- struct tss_struct *t = &per_cpu(cpu_tss, cpu);
#ifdef CONFIG_X86_64
struct desc_struct *desc = get_cpu_gdt_rw(cpu);
tss_desc tss;
#endif
- set_tss_desc(cpu, t); /*
- * This just modifies memory; should not be
- * necessary. But... This is necessary, because
- * 386 hardware has concept of busy TSS or some
- * similar stupidity.
- */
+
+ /*
+ * We need to reload TR, which requires that we change the
+ * GDT entry to indicate "available" first.
+ *
+ * XXX: This could probably all be replaced by a call to
+ * force_reload_TR().
+ */
+ set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
#ifdef CONFIG_X86_64
memcpy(&tss, &desc[GDT_ENTRY_TSS], sizeof(tss_desc));
write_gdt_entry(desc, GDT_ENTRY_TSS, &tss, DESC_TSS);
syscall_init(); /* This sets MSR_*STAR and related */
+#else
+ if (boot_cpu_has(X86_FEATURE_SEP))
+ enable_sep_cpu();
#endif
load_TR_desc(); /* This does ltr */
load_mm_ldt(current->active_mm); /* This does lldt */
}
/**
- * __restore_processor_state - restore the contents of CPU registers saved
- * by __save_processor_state()
- * @ctxt - structure to load the registers contents from
+ * __restore_processor_state - restore the contents of CPU registers saved
+ * by __save_processor_state()
+ * @ctxt - structure to load the registers contents from
+ *
+ * The asm code that gets us here will have restored a usable GDT, although
+ * it will be pointing to the wrong alias.
*/
static void notrace __restore_processor_state(struct saved_context *ctxt)
{
write_cr2(ctxt->cr2);
write_cr0(ctxt->cr0);
+ /* Restore the IDT. */
+ load_idt(&ctxt->idt);
+
/*
- * now restore the descriptor tables to their proper values
- * ltr is done i fix_processor_context().
+ * Just in case the asm code got us here with the SS, DS, or ES
+ * out of sync with the GDT, update them.
*/
-#ifdef CONFIG_X86_32
- load_idt(&ctxt->idt);
-#else
-/* CONFIG_X86_64 */
- load_idt((const struct desc_ptr *)&ctxt->idt_limit);
-#endif
+ loadsegment(ss, __KERNEL_DS);
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
-#ifdef CONFIG_X86_64
/*
- * We need GSBASE restored before percpu access can work.
- * percpu access can happen in exception handlers or in complicated
- * helpers like load_gs_index().
+ * Restore percpu access. Percpu access can happen in exception
+ * handlers or in complicated helpers like load_gs_index().
*/
- wrmsrl(MSR_GS_BASE, ctxt->gs_base);
+#ifdef CONFIG_X86_64
+ wrmsrl(MSR_GS_BASE, ctxt->kernelmode_gs_base);
+#else
+ loadsegment(fs, __KERNEL_PERCPU);
+ loadsegment(gs, __KERNEL_STACK_CANARY);
#endif
+ /* Restore the TSS, RO GDT, LDT, and usermode-relevant MSRs. */
fix_processor_context();
/*
- * Restore segment registers. This happens after restoring the GDT
- * and LDT, which happen in fix_processor_context().
+ * Now that we have descriptor tables fully restored and working
+ * exception handling, restore the usermode segments.
*/
-#ifdef CONFIG_X86_32
+#ifdef CONFIG_X86_64
+ loadsegment(ds, ctxt->es);
loadsegment(es, ctxt->es);
loadsegment(fs, ctxt->fs);
- loadsegment(gs, ctxt->gs);
- loadsegment(ss, ctxt->ss);
-
- /*
- * sysenter MSRs
- */
- if (boot_cpu_has(X86_FEATURE_SEP))
- enable_sep_cpu();
-#else
-/* CONFIG_X86_64 */
- asm volatile ("movw %0, %%ds" :: "r" (ctxt->ds));
- asm volatile ("movw %0, %%es" :: "r" (ctxt->es));
- asm volatile ("movw %0, %%fs" :: "r" (ctxt->fs));
load_gs_index(ctxt->gs);
- asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss));
/*
- * Restore FSBASE and user GSBASE after reloading the respective
- * segment selectors.
+ * Restore FSBASE and GSBASE after restoring the selectors, since
+ * restoring the selectors clobbers the bases. Keep in mind
+ * that MSR_KERNEL_GS_BASE is horribly misnamed.
*/
wrmsrl(MSR_FS_BASE, ctxt->fs_base);
- wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
+ wrmsrl(MSR_KERNEL_GS_BASE, ctxt->usermode_gs_base);
+#elif defined(CONFIG_X86_32_LAZY_GS)
+ loadsegment(gs, ctxt->gs);
#endif
do_fpu_end();
git.samba.org / sfrench / cifs-2.6.git / blobdiff