Commit 51580749 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge git://kvm.qumranet.com/home/avi/kvm 

* git://kvm.qumranet.com/home/avi/kvm:
  KVM: always reload segment selectors
  KVM: Prevent system selectors leaking into guest on real->protected mode transition on vmx
parents 436ce716 6d9658df

drivers/kvm/vmx.c

+22 −17
Original line number Diff line number Diff line
@@ -618,7 +618,7 @@ static void fix_pmode_dataseg(int seg, struct kvm_save_segment *save) 
{

	struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];



	if (vmcs_readl(sf->base) == save->base) {

	if (vmcs_readl(sf->base) == save->base && (save->base & AR_S_MASK)) {

		vmcs_write16(sf->selector, save->selector);

		vmcs_writel(sf->base, save->base);

		vmcs_write32(sf->limit, save->limit);
@@ -1888,6 +1888,27 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) 
		[cr2]"i"(offsetof(struct kvm_vcpu, cr2))

	      : "cc", "memory" );



	/*

	 * Reload segment selectors ASAP. (it's needed for a functional

	 * kernel: x86 relies on having __KERNEL_PDA in %fs and x86_64

	 * relies on having 0 in %gs for the CPU PDA to work.)

	 */

	if (fs_gs_ldt_reload_needed) {

		load_ldt(ldt_sel);

		load_fs(fs_sel);

		/*

		 * If we have to reload gs, we must take care to

		 * preserve our gs base.

		 */

		local_irq_disable();

		load_gs(gs_sel);

#ifdef CONFIG_X86_64

		wrmsrl(MSR_GS_BASE, vmcs_readl(HOST_GS_BASE));

#endif

		local_irq_enable();



		reload_tss();

	}

	++kvm_stat.exits;



	save_msrs(vcpu->guest_msrs, NR_BAD_MSRS);
@@ -1905,22 +1926,6 @@ static int vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) 
		kvm_run->exit_reason = vmcs_read32(VM_INSTRUCTION_ERROR);

		r = 0;

	} else {

		if (fs_gs_ldt_reload_needed) {

			load_ldt(ldt_sel);

			load_fs(fs_sel);

			/*

			 * If we have to reload gs, we must take care to

			 * preserve our gs base.

			 */

			local_irq_disable();

			load_gs(gs_sel);

#ifdef CONFIG_X86_64

			wrmsrl(MSR_GS_BASE, vmcs_readl(HOST_GS_BASE));

#endif

			local_irq_enable();



			reload_tss();

		}

		/*

		 * Profile KVM exit RIPs:

		 */