Re: [patch] kvm: suppress KVM_SET_GSI_ROUTING allocation failure

From: Paolo Bonzini
Date: Tue Feb 13 2018 - 10:17:09 EST


On 13/02/2018 16:14, Christian Borntraeger wrote:
> On 02/08/2018 10:35 PM, David Rientjes wrote:
>> The KVM_SET_GSI_ROUTING ioctl does a vmalloc() of
>> sizeof(struct kvm_irq_routing_entry) multiplied by a user-supplied value.
>> This can be up to 4096 entries on architectures such as arm64 and s390
>> (and the upper bound may be increased on s390 eventually).
>>
>> This can produce a vmalloc allocation failure warning:
>>
> [...]
>> kvm_vm_ioctl+0x910/0x15e0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4153
>
> ^^^^^
>
>> @@ -3063,7 +3063,8 @@ static long kvm_vm_ioctl(struct file *filp,
>
> ^^^^^
>
>
> Are you sure that you got the right vmalloc?

Nice catch! But well, it's the only one in the whole file. :)

That seems very much like an old patch then. I'm unqueuing it.

Paolo