diff options
| author | Andy Lutomirski <[email protected]> | 2016-10-31 15:18:45 -0700 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2016-11-01 07:47:54 +0100 |
| commit | 04ac88abaf758bd76edcc3be5549003a017e7963 (patch) | |
| tree | 612ffedd93d67ecb289f3af1848529192f253387 | |
| parent | 5a83d60c074ddf4f6364be25654a643d0e941824 (diff) | |
x86/fpu, kvm: Remove host CR0.TS manipulation
Now that x86 always uses eager FPU switching on the host, there's no
need for KVM to manipulate the host's CR0.TS.
This should be both simpler and faster.
Signed-off-by: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Quentin Casasnovas <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: kvm list <[email protected]>
Link: http://lkml.kernel.org/r/b212064922537c05d0c81d931fc4dbe769127ce7.1477951965.git.luto@kernel.org
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/kvm/vmx.c | 12 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 |
2 files changed, 4 insertions, 13 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index cf1b16dbc98a..531c44633190 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2144,12 +2144,6 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx) #endif if (vmx->host_state.msr_host_bndcfgs) wrmsrl(MSR_IA32_BNDCFGS, vmx->host_state.msr_host_bndcfgs); - /* - * If the FPU is not active (through the host task or - * the guest vcpu), then restore the cr0.TS bit. - */ - if (!fpregs_active() && !vmx->vcpu.guest_fpu_loaded) - stts(); load_gdt(this_cpu_ptr(&host_gdt)); } @@ -4871,9 +4865,11 @@ static void vmx_set_constant_host_state(struct vcpu_vmx *vmx) u32 low32, high32; unsigned long tmpl; struct desc_ptr dt; - unsigned long cr4; + unsigned long cr0, cr4; - vmcs_writel(HOST_CR0, read_cr0() & ~X86_CR0_TS); /* 22.2.3 */ + cr0 = read_cr0(); + WARN_ON(cr0 & X86_CR0_TS); + vmcs_writel(HOST_CR0, cr0); /* 22.2.3 */ vmcs_writel(HOST_CR3, read_cr3()); /* 22.2.3 FIXME: shadow tables */ /* Save the most likely value for this task's CR4 in the VMCS. */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 7f9fa2d8f4e4..cfe6a75b5358 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5060,11 +5060,6 @@ static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt) { preempt_disable(); kvm_load_guest_fpu(emul_to_vcpu(ctxt)); - /* - * CR0.TS may reference the host fpu state, not the guest fpu state, - * so it may be clear at this point. - */ - clts(); } static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt) |