From 4186ae815556590798de371e0d6ed85fc3682534 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 13 Jul 2018 16:23:18 +0200 Subject: x86/l1tf: Handle EPT disabled state proper commit a7b9020b06ec6d7c3f3b0d4ef1a9eba12654f4f7 upstream If Extended Page Tables (EPT) are disabled or not supported, no L1D flushing is required. The setup function can just avoid setting up the L1D flush for the EPT=n case. Invoke it after the hardware setup has be done and enable_ept has the correct state and expose the EPT disabled state in the mitigation status as well. Signed-off-by: Thomas Gleixner Tested-by: Jiri Kosina Reviewed-by: Greg Kroah-Hartman Reviewed-by: Josh Poimboeuf Link: https://lkml.kernel.org/r/20180713142322.612160168@linutronix.de Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx.c | 44 ++++++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 18 deletions(-) (limited to 'arch/x86/kvm') diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 8155a4d545a4..1811aeef4f41 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -11659,6 +11659,11 @@ static int __init vmx_setup_l1d_flush(void) if (!boot_cpu_has_bug(X86_BUG_L1TF)) return 0; + if (!enable_ept) { + l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_EPT_DISABLED; + return 0; + } + l1tf_vmx_mitigation = vmentry_l1d_flush; if (vmentry_l1d_flush == VMENTER_L1D_FLUSH_NEVER) @@ -11685,18 +11690,35 @@ static void vmx_cleanup_l1d_flush(void) l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO; } + +static void vmx_exit(void) +{ +#ifdef CONFIG_KEXEC_CORE + RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL); + synchronize_rcu(); +#endif + + kvm_exit(); + + vmx_cleanup_l1d_flush(); +} +module_exit(vmx_exit) + static int __init vmx_init(void) { int r; - r = vmx_setup_l1d_flush(); + r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx), + __alignof__(struct vcpu_vmx), THIS_MODULE); if (r) return r; - r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx), - __alignof__(struct vcpu_vmx), THIS_MODULE); + /* + * Must be called after kvm_init() so enable_ept is properly set up + */ + r = vmx_setup_l1d_flush(); if (r) { - vmx_cleanup_l1d_flush(); + vmx_exit(); return r; } @@ -11707,18 +11729,4 @@ static int __init vmx_init(void) return 0; } - -static void __exit vmx_exit(void) -{ -#ifdef CONFIG_KEXEC_CORE - RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL); - synchronize_rcu(); -#endif - - kvm_exit(); - - vmx_cleanup_l1d_flush(); -} - module_init(vmx_init) -module_exit(vmx_exit) -- cgit v1.2.3