[RFC PATCH 5/8]: PVH: smp changes

[Mukesh Rathor <mukesh.rathor@oracle.com>]

---
 arch/x86/xen/smp.c |   33 +++++++++++++++++++++++++--------
 1 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index cdf269d..017d7fa 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -68,9 +68,11 @@ static void __cpuinit cpu_bringup(void)
 	touch_softlockup_watchdog();
 	preempt_disable();
 
-	xen_enable_sysenter();
-	xen_enable_syscall();
-
+	/* PVH runs in ring 0 and allows us to do native syscalls. Yay! */
+	if (!xen_pvh_domain()) {
+		xen_enable_sysenter();
+		xen_enable_syscall();
+	}
 	cpu = smp_processor_id();
 	smp_store_cpu_info(cpu);
 	cpu_data(cpu).x86_max_cores = 1;
@@ -230,10 +232,11 @@ static void __init xen_smp_prepare_boot_cpu(void)
 	BUG_ON(smp_processor_id() != 0);
 	native_smp_prepare_boot_cpu();
 
-	/* We've switched to the "real" per-cpu gdt, so make sure the
-	   old memory can be recycled */
-	make_lowmem_page_readwrite(xen_initial_gdt);
-
+	if (!xen_pvh_domain()) {
+		/* We've switched to the "real" per-cpu gdt, so make sure the
+		 * old memory can be recycled */
+		make_lowmem_page_readwrite(xen_initial_gdt);
+	}
 	xen_filter_cpu_maps();
 	xen_setup_vcpu_info_placement();
 }
@@ -312,6 +315,7 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 
 	memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
 
+	if (!xen_pvh_domain()) {
 		ctxt->user_regs.ds = __USER_DS;
 		ctxt->user_regs.es = __USER_DS;
 
@@ -339,7 +343,20 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 					(unsigned long)xen_hypervisor_callback;
 		ctxt->failsafe_callback_eip = 
 					(unsigned long)xen_failsafe_callback;
-
+	} else {
+		ctxt->user_regs.ds = __KERNEL_DS;
+		ctxt->user_regs.es = 0;
+		ctxt->user_regs.gs = 0;
+
+		ctxt->gdt_frames[0] = (unsigned long)gdt;
+		ctxt->gdt_ents = (unsigned long)(GDT_SIZE - 1);
+
+		/* Note: PVH is not supported on x86_32. */
+#ifdef __x86_64__
+		ctxt->gs_base_user = (unsigned long)
+		                         per_cpu(irq_stack_union.gs_base, cpu);
+#endif
+	}
 	ctxt->user_regs.cs = __KERNEL_CS;
 	ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
 
-- 
1.7.2.3