From: Andrew Cooper Date: Tue, 17 Oct 2017 17:06:23 +0000 (+0100) Subject: x86/vmx: Don't rewrite HOST_TR_SELECTOR on every context switch X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~985 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=cec618383b3d8e03411a6abb194fd63b15f4444e;p=xen.git x86/vmx: Don't rewrite HOST_TR_SELECTOR on every context switch TSS_ENTRY is a compile time constant, so HOST_TR_SELECTOR can be set up during VMCS construction and left alone thereafter, rather than rewriting it on every context switch. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich Acked-by: Kevin Tian --- diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c index b5100b5021..6042109071 100644 --- a/xen/arch/x86/hvm/vmx/vmcs.c +++ b/xen/arch/x86/hvm/vmx/vmcs.c @@ -806,7 +806,6 @@ static void vmx_set_host_env(struct vcpu *v) (unsigned long)(this_cpu(gdt_table) - FIRST_RESERVED_GDT_ENTRY)); __vmwrite(HOST_IDTR_BASE, (unsigned long)idt_tables[cpu]); - __vmwrite(HOST_TR_SELECTOR, TSS_ENTRY << 3); __vmwrite(HOST_TR_BASE, (unsigned long)&per_cpu(init_tss, cpu)); __vmwrite(HOST_SYSENTER_ESP, get_stack_bottom()); @@ -1144,6 +1143,7 @@ static int construct_vmcs(struct vcpu *v) __vmwrite(HOST_GS_SELECTOR, 0); __vmwrite(HOST_FS_BASE, 0); __vmwrite(HOST_GS_BASE, 0); + __vmwrite(HOST_TR_SELECTOR, TSS_ENTRY << 3); /* Host control registers. */ v->arch.hvm_vmx.host_cr0 = read_cr0() | X86_CR0_TS;