[PATCH v1 08/12] xen/hvmlite: Initialize context for secondary VCPUs

From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
To: david.vrabel@citrix.com, konrad.wilk@oracle.com
Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org,
	roger.pau@citrix.com, mcgrof@suse.com,
	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: [PATCH v1 08/12] xen/hvmlite: Initialize context for secondary VCPUs
Date: Fri, 22 Jan 2016 16:35:54 -0500	[thread overview]
Message-ID: <1453498558-6028-9-git-send-email-boris.ostrovsky@oracle.com> (raw)
In-Reply-To: <1453498558-6028-1-git-send-email-boris.ostrovsky@oracle.com>

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
 arch/x86/xen/smp.c         |   57 ++++++++++++++++++++++++++++++++++++++++----
 arch/x86/xen/smp.h         |    4 +++
 arch/x86/xen/xen-hvmlite.S |    7 +++++
 3 files changed, 63 insertions(+), 5 deletions(-)

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 5fc4afb..b265c4f 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -27,6 +27,7 @@
 #include <xen/interface/xen.h>
 #include <xen/interface/vcpu.h>
 #include <xen/interface/xenpmu.h>
+#include <xen/interface/hvm/hvm_vcpu.h>
 
 #include <asm/xen/interface.h>
 #include <asm/xen/hypercall.h>
@@ -384,6 +385,7 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 	struct vcpu_guest_context *ctxt;
 	struct desc_struct *gdt;
 	unsigned long gdt_mfn;
+	void *ctxt_arg;
 
 	/* used to tell cpu_init() that it can proceed with initialization */
 	cpumask_set_cpu(cpu, cpu_callout_mask);
@@ -392,7 +394,7 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 
 	if (!xen_hvmlite) {
 
-		ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
+		ctxt_arg = ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
 		if (ctxt == NULL)
 			return -ENOMEM;
 
@@ -460,14 +462,59 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 		ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
 		ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_gfn(swapper_pg_dir));
 	} else {
-		ctxt = NULL; /* To quiet down compiler */
-		BUG();
+#ifdef CONFIG_XEN_PVHVM
+		struct vcpu_hvm_context *hctxt;
+
+		ctxt_arg = hctxt = kzalloc(sizeof(*hctxt), GFP_KERNEL);
+		if (hctxt == NULL)
+			return -ENOMEM;
+
+#ifdef CONFIG_X86_64
+		hctxt->mode = VCPU_HVM_MODE_64B;
+		hctxt->cpu_regs.x86_64.rip =
+			(unsigned long)secondary_startup_64;
+		hctxt->cpu_regs.x86_64.rsp = stack_start;
+
+		hctxt->cpu_regs.x86_64.cr0 =
+			X86_CR0_PG | X86_CR0_WP | X86_CR0_PE;
+		hctxt->cpu_regs.x86_64.cr4 = X86_CR4_PAE;
+		hctxt->cpu_regs.x86_64.cr3 =
+			xen_pfn_to_cr3(virt_to_mfn(init_level4_pgt));
+		hctxt->cpu_regs.x86_64.efer = EFER_LME | EFER_NX;
+#else
+		hctxt->mode = VCPU_HVM_MODE_32B;
+		/*
+		 * startup_32_smp expects GDT loaded so we can't jump
+		 * there directly.
+		 */
+		hctxt->cpu_regs.x86_32.eip =
+			(unsigned long)hvmlite_smp_32 - __START_KERNEL_map;
+
+		hctxt->cpu_regs.x86_32.cr0 = X86_CR0_PE;
+
+		hctxt->cpu_regs.x86_32.cs_base = 0;
+		hctxt->cpu_regs.x86_32.cs_limit = ~0u;
+		hctxt->cpu_regs.x86_32.cs_ar = 0xc9b;
+		hctxt->cpu_regs.x86_32.ds_base = 0;
+		hctxt->cpu_regs.x86_32.ds_limit = ~0u;
+		hctxt->cpu_regs.x86_32.ds_ar = 0xc93;
+		hctxt->cpu_regs.x86_32.es_base = 0;
+		hctxt->cpu_regs.x86_32.es_limit = ~0u;
+		hctxt->cpu_regs.x86_32.es_ar = 0xc93;
+		hctxt->cpu_regs.x86_32.ss_base = 0;
+		hctxt->cpu_regs.x86_32.ss_limit = ~0u;
+		hctxt->cpu_regs.x86_32.ss_ar = 0xc93;
+		hctxt->cpu_regs.x86_32.tr_base = 0;
+		hctxt->cpu_regs.x86_32.tr_limit = 0xff;
+		hctxt->cpu_regs.x86_32.tr_ar = 0x8b;
+#endif
+#endif
 	}
 
-	if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
+	if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt_arg))
 		BUG();
 
-	kfree(ctxt);
+	kfree(ctxt_arg);
 	return 0;
 }
 
diff --git a/arch/x86/xen/smp.h b/arch/x86/xen/smp.h
index 963d62a..b4a833c 100644
--- a/arch/x86/xen/smp.h
+++ b/arch/x86/xen/smp.h
@@ -8,6 +8,10 @@ extern void xen_send_IPI_allbutself(int vector);
 extern void xen_send_IPI_all(int vector);
 extern void xen_send_IPI_self(int vector);
 
+#ifdef CONFIG_X86_32
+extern void hvmlite_smp_32(void);
+#endif
+
 #ifdef CONFIG_XEN_PVH
 extern void xen_pvh_early_cpu_init(int cpu, bool entry);
 #else
diff --git a/arch/x86/xen/xen-hvmlite.S b/arch/x86/xen/xen-hvmlite.S
index 90f03d0..8d6a642 100644
--- a/arch/x86/xen/xen-hvmlite.S
+++ b/arch/x86/xen/xen-hvmlite.S
@@ -134,6 +134,13 @@ ENTRY(hvmlite_start_xen)
 	ljmp    $0x10, $_pa(startup_32)
 #endif
 
+#ifdef CONFIG_X86_32
+ENTRY(hvmlite_smp_32)
+        mov $_pa(boot_gdt_descr), %eax
+        lgdt (%eax)
+        jmp startup_32_smp
+#endif
+
 	.data
 gdt:
 	.word	gdt_end - gdt
-- 
1.7.1
