kvm: svm: fix unsigned compare less than zero comparison

vm_data->avic_vm_id is a u32, so the check for a error
return (less than zero) such as -EAGAIN from
avic_get_next_vm_id currently has no effect whatsoever.
Fix this by using a temporary int for the comparison
and assign vm_data->avic_vm_id to this. I used an explicit
u32 cast in the assignment to show why vm_data->avic_vm_id
cannot be used in the assign/compare steps.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Colin Ian King 2016-09-19 07:11:59 +01:00 committed by Paolo Bonzini
parent 095cf55df7
commit adad0d02a7

View File

@ -1412,7 +1412,7 @@ static void avic_vm_destroy(struct kvm *kvm)
static int avic_vm_init(struct kvm *kvm)
{
unsigned long flags;
int err = -ENOMEM;
int vm_id, err = -ENOMEM;
struct kvm_arch *vm_data = &kvm->arch;
struct page *p_page;
struct page *l_page;
@ -1420,9 +1420,10 @@ static int avic_vm_init(struct kvm *kvm)
if (!avic)
return 0;
vm_data->avic_vm_id = avic_get_next_vm_id();
if (vm_data->avic_vm_id < 0)
return vm_data->avic_vm_id;
vm_id = avic_get_next_vm_id();
if (vm_id < 0)
return vm_id;
vm_data->avic_vm_id = (u32)vm_id;
/* Allocating physical APIC ID table (4KB) */
p_page = alloc_page(GFP_KERNEL);