Re: [PATCH 2/3] xen/x86: address violations of MISRA C:2012 Rule 14.4

[Jan Beulich <jbeulich@xxxxxxxx>]

On 07.12.2023 14:53, Simone Ballarin wrote:
> On 07/12/23 11:54, Jan Beulich wrote:
>> On 07.12.2023 10:48, Simone Ballarin wrote:
>>> --- a/xen/arch/x86/hpet.c
>>> +++ b/xen/arch/x86/hpet.c
>>> @@ -279,7 +279,7 @@ static int hpet_msi_write(struct hpet_event_channel 
>>> *ch, struct msi_msg *msg)
>>>   {
>>>       ch->msi.msg = *msg;
>>>   
>>> -    if ( iommu_intremap )
>>> +    if ( iommu_intremap != iommu_intremap_off )
>>>       {
>>>           int rc = iommu_update_ire_from_msi(&ch->msi, msg);
>>>   
>>> @@ -353,7 +353,7 @@ static int __init hpet_setup_msi_irq(struct 
>>> hpet_event_channel *ch)
>>>       u32 cfg = hpet_read32(HPET_Tn_CFG(ch->idx));
>>>       irq_desc_t *desc = irq_to_desc(ch->msi.irq);
>>>   
>>> -    if ( iommu_intremap )
>>> +    if ( iommu_intremap != iommu_intremap_off )
>>>       {
>>>           ch->msi.hpet_id = hpet_blockid;
>>>           ret = iommu_setup_hpet_msi(&ch->msi);
>>> @@ -372,7 +372,7 @@ static int __init hpet_setup_msi_irq(struct 
>>> hpet_event_channel *ch)
>>>           ret = __hpet_setup_msi_irq(desc);
>>>       if ( ret < 0 )
>>>       {
>>> -        if ( iommu_intremap )
>>> +        if ( iommu_intremap != iommu_intremap_off )
>>>               iommu_update_ire_from_msi(&ch->msi, NULL);
>>>           return ret;
>>>       }
>>> diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
>>> index 7f8e794254..72dce2e4ab 100644
>>> --- a/xen/arch/x86/msi.c
>>> +++ b/xen/arch/x86/msi.c
>>> @@ -189,7 +189,7 @@ static int write_msi_msg(struct msi_desc *entry, struct 
>>> msi_msg *msg)
>>>   {
>>>       entry->msg = *msg;
>>>   
>>> -    if ( iommu_intremap )
>>> +    if ( iommu_intremap != iommu_intremap_off )
>>>       {
>>>           int rc;
>>>   
>>> @@ -555,7 +555,7 @@ int msi_free_irq(struct msi_desc *entry)
>>>               destroy_irq(entry[nr].irq);
>>>   
>>>           /* Free the unused IRTE if intr remap enabled */
>>> -        if ( iommu_intremap )
>>> +        if ( iommu_intremap != iommu_intremap_off )
>>>               iommu_update_ire_from_msi(entry + nr, NULL);
>>>       }
>>>   
>>
>> All of this would logically be part of patch 1. Is there a particular reason
>> why it wasn't done right there?
> 
> These changes and the ones in patch 1 are related, but still remain
> independent. Patch 1 can be accepted without patch 2 and vice versa.
> So we've decided to split the commits because patch 1 is in common
> code, while patch 2 is in x86-specific code.

Just to clarify: While not located under arch/x86/, what patch 1 touches
is still x86-specific code. It's subject prefix also wrongly says
AMD/IOMMU: when it also touches VT-d code. Especially with the changes
here folded in, x86/IOMMU: might be more appropriate.

Jan