Re: [PATCH v8 12/12] iommu: Use refcount for fault data access

Baolu Lu
2023-12-13T02:18:45Z

On 12/12/23 11:14 PM, Jason Gunthorpe wrote:
> On Tue, Dec 12, 2023 at 01:17:47PM +0800, Baolu Lu wrote:
>> On 12/11/23 11:24 PM, Jason Gunthorpe wrote:
>>> Also iopf_queue_remove_device() is messed up - it returns an error
>>> code but nothing ever does anything with it 🙁 Remove functions like
>>> this should never fail.
>> Yes, agreed.
>>
>>> Removal should be like I explained earlier:
>>> - Disable new PRI reception
>> This could be done by
>>
>> rcu_assign_pointer(param->fault_param, NULL);
>>
>> ?
> Not without a synchronize_rcu
>
> disable new PRI reception should be done by the driver - it should
> turn off PRI generation in the IOMMU HW and flush any HW PRI queues.

Yeah! Get you now.

Best regards,
baolu