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[PATCH] KVM: Fix GFP_KERNEL alloc in atomic section bug

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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 <mingo@elte.hu>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Ingo Molnar 2007-01-05 16:36:23 -08:00 committed by Linus Torvalds
parent cd36beec0b
commit 965b58a550
1 changed files with 21 additions and 11 deletions
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32
drivers/kvm/vmx.c
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@ -1094,14 +1094,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu)
rdmsrl(MSR_IA32_SYSENTER_EIP, a); rdmsrl(MSR_IA32_SYSENTER_EIP, a);
vmcs_writel(HOST_IA32_SYSENTER_EIP, a); /* 22.2.3 */ 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) { for (i = 0; i < NR_VMX_MSR; ++i) {
u32 index = vmx_msr_index[i]; u32 index = vmx_msr_index[i];
u32 data_low, data_high; u32 data_low, data_high;
@ -1155,8 +1147,6 @@ static int vmx_vcpu_setup(struct kvm_vcpu *vcpu)
return 0; return 0;
out_free_guest_msrs:
kfree(vcpu->guest_msrs);
out: out:
return ret; return ret;
} }
@ -1906,13 +1896,33 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
{ {
struct vmcs *vmcs; 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(); vmcs = alloc_vmcs();
if (!vmcs) if (!vmcs)
return -ENOMEM; goto out_free_msrs;
vmcs_clear(vmcs); vmcs_clear(vmcs);
vcpu->vmcs = vmcs; vcpu->vmcs = vmcs;
vcpu->launched = 0; vcpu->launched = 0;
return 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 = { static struct kvm_arch_ops vmx_arch_ops = {