[patch 157/164] KVM: x86: Add missing locking to arch specific vcpu ioctls

Greg KH
2010-07-01T20:58:11Z

2.6.33-stable review patch. If anyone has any objections, please let me know.

------------------

From: Avi Kivity <avi@redhat.com>

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 8fbf065d625617bbbf6b72d5f78f84ad13c8b547)
---
arch/x86/kvm/x86.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1550,6 +1550,7 @@ static int kvm_vcpu_ioctl_get_cpuid2(str
{
int r;

+ vcpu_load(vcpu);
r = -E2BIG;
if (cpuid->nent < vcpu->arch.cpuid_nent)
goto out;
@@ -1561,6 +1562,7 @@ static int kvm_vcpu_ioctl_get_cpuid2(str

out:
cpuid->nent = vcpu->arch.cpuid_nent;
+ vcpu_put(vcpu);
return r;
}

@@ -1813,6 +1815,7 @@ static int kvm_vcpu_ioctl_x86_setup_mce(
int r;
unsigned bank_num = mcg_cap & 0xff, bank;

+ vcpu_load(vcpu);
r = -EINVAL;
if (!bank_num || bank_num >= KVM_MAX_MCE_BANKS)
goto out;
@@ -1827,6 +1830,7 @@ static int kvm_vcpu_ioctl_x86_setup_mce(
for (bank = 0; bank < bank_num; bank++)
vcpu->arch.mce_banks[bank*4] = ~(u64)0;
out:
+ vcpu_put(vcpu);
return r;
}

@@ -2094,7 +2098,9 @@ long kvm_arch_vcpu_ioctl(struct file *fi
r = -EFAULT;
if (copy_from_user(&mce, argp, sizeof mce))
goto out;
+ vcpu_load(vcpu);
r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce);
+ vcpu_put(vcpu);
break;
}
case KVM_GET_VCPU_EVENTS: {