Re: [PATCH 1/1] iommu/sva: Invalidate KVA range on kernel TLB flush

[Baolu Lu <baolu.lu@linux.intel.com>]

On 7/8/25 22:06, Jason Gunthorpe wrote:
> On Tue, Jul 08, 2025 at 09:27:55AM -0300, Jason Gunthorpe wrote:
>> On Tue, Jul 08, 2025 at 01:42:53PM +0800, Baolu Lu wrote:
>>>> +void iommu_sva_invalidate_kva_range(unsigned long start, unsigned long end)
>>>> +{
>>>> +	struct iommu_mm_data *iommu_mm;
>>>> +
>>>> +	might_sleep();
>>>
>>> Yi Lai <yi1.lai@intel.com> reported an issue here. This interface could
>>> potentially be called in a non-sleepable context.
>>
>> Oh thats really bad, the notifiers inside the iommu driver are not
>> required to be called in a sleepable context either and I don't really
>> want to change that requirement.
> 
> Actually, I have got confused here with the hmm use of notifiers.
> 
> The iommu drivers use arch_invalidate_secondary_tlbs so they are
> already in atomic contexts.
> 
> So your idea to use a spinlock seems correct.

Okay, then let me post an updated version.

Thanks,
baolu