From: Ingo Molnar 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 --- drivers/kvm/vmx.c | 32 +++++++++++++++++++++----------- 1 files changed, 21 insertions(+), 11 deletions(-) diff -puN drivers/kvm/vmx.c~kvm-fix-gfp_kernel-alloc-in-atomic-section-bug drivers/kvm/vmx.c --- a/drivers/kvm/vmx.c~kvm-fix-gfp_kernel-alloc-in-atomic-section-bug +++ a/drivers/kvm/vmx.c @@ -1094,14 +1094,6 @@ static int vmx_vcpu_setup(struct kvm_vcp 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_vcp return 0; -out_free_guest_msrs: - kfree(vcpu->guest_msrs); out: return ret; } @@ -1906,13 +1896,33 @@ static int vmx_create_vcpu(struct kvm_vc { 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 = { _