From 965b58a550b6f84815cb555e6abb953e863f1610 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 5 Jan 2007 16:36:23 -0800 Subject: [PATCH] [PATCH] KVM: Fix GFP_KERNEL alloc in atomic section bug KVM does kmalloc() in an atomic section while having preemption disabled via vcpu_load(). Fix this by moving the ->*_msr setup from the vcpu_setup method to the vcpu_create method. (This is also a small speedup for setting up a vcpu, which can in theory be more frequent than the vcpu_create method). Signed-off-by: Ingo Molnar Signed-off-by: Avi Kivity Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/kvm/vmx.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index d0a2c2d5342a..fbab07af6574 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -1094,14 +1094,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu) rdmsrl(MSR_IA32_SYSENTER_EIP, a); vmcs_writel(HOST_IA32_SYSENTER_EIP, a); /* 22.2.3 */ - ret = -ENOMEM; - vcpu->guest_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!vcpu->guest_msrs) - goto out; - vcpu->host_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!vcpu->host_msrs) - goto out_free_guest_msrs; - for (i = 0; i < NR_VMX_MSR; ++i) { u32 index = vmx_msr_index[i]; u32 data_low, data_high; @@ -1155,8 +1147,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu) return 0; -out_free_guest_msrs: - kfree(vcpu->guest_msrs); out: return ret; } @@ -1906,13 +1896,33 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) { struct vmcs *vmcs; + vcpu->guest_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!vcpu->guest_msrs) + return -ENOMEM; + + vcpu->host_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!vcpu->host_msrs) + goto out_free_guest_msrs; + vmcs = alloc_vmcs(); if (!vmcs) - return -ENOMEM; + goto out_free_msrs; + vmcs_clear(vmcs); vcpu->vmcs = vmcs; vcpu->launched = 0; + return 0; + +out_free_msrs: + kfree(vcpu->host_msrs); + vcpu->host_msrs = NULL; + +out_free_guest_msrs: + kfree(vcpu->guest_msrs); + vcpu->guest_msrs = NULL; + + return -ENOMEM; } static struct kvm_arch_ops vmx_arch_ops = { -- 2.20.1