Re: [PATCH] amd iommu: Fix a return value of guest_iommu_set_base()

[Wei Wang <wei.wang2@amd.com>]

On 02/03/2012 05:35 PM, Jan Beulich wrote:
>>>> On 03.02.12 at 16:29, Wei Wang<wei.wang2@amd.com>  wrote:
>> # HG changeset patch
>> # User Wei Wang<wei.wang2@amd.com>
>> # Date 1328282938 -3600
>> # Node ID 58a2281581a4c4171ca52549b3e8062b9733ec2b
>> # Parent  3432abcf9380d3840ca38439a304f74a37d155fc
>> amd iommu: Fix a return value of guest_iommu_set_base()
>> Remove a unnecessary check in guest_iommu_destroy()
>>
>> Signed-off-by: Wei Wang<wei.wang2@amd.com>
>>
>> diff -r 3432abcf9380 -r 58a2281581a4 xen/drivers/passthrough/amd/iommu_guest.c
>> --- a/xen/drivers/passthrough/amd/iommu_guest.c	Thu Feb 02 15:47:26 2012 +0000
>> +++ b/xen/drivers/passthrough/amd/iommu_guest.c	Fri Feb 03 16:28:58 2012
>> +0100
>> @@ -806,7 +806,7 @@ int guest_iommu_set_base(struct domain *
>>       struct guest_iommu *iommu = domain_iommu(d);
>>
>>       if ( !is_hvm_domain(d) || !iommu_enabled || !iommuv2_enabled )
>> -        return 0;
>> +        return -EACCES;
>
> But as indicated before, all three checks above are redundant with
> the one check below. Hence I suggested to remove the checks above,
> and if you wish put an ASSERT() past the !iommu check below.

OK,then I remove them all. I will send a new thread for the patch.
Thanks,
Wei

> Jan
>
>>
>>       if ( !iommu )
>>           return -EACCES;
>> @@ -896,9 +896,6 @@ void guest_iommu_destroy(struct domain *
>>   {
>>       struct guest_iommu *iommu;
>>
>> -    if ( !is_hvm_domain(d) || !iommu_enabled || !iommuv2_enabled )
>> -        return;
>> -
>>       iommu = domain_iommu(d);
>>       if ( !iommu )
>>           return;
>
>
>
>