Re: [PATCH] iommu/vt-d: Remove unnecessary locking in intel_irq_remapping_alloc()

Baolu Lu
2023-03-27T13:13:19Z

On 2023/3/27 20:18, Jason Gunthorpe wrote:
> On Tue, Mar 14, 2023 at 01:18:36PM +0800, Lu Baolu wrote:
>> The global rwsem dmar_global_lock was introduced by commit 3a5670e8ac932
>> ("iommu/vt-d: Introduce a rwsem to protect global data structures"). It
>> is used to protect DMAR related global data from DMAR hotplug operations.
>>
>> Using dmar_global_lock in intel_irq_remapping_alloc() is unnecessary as
>> the DMAR global data structures are not touched there. Remove it to avoid
>> below lockdep warning.
>
> Tested-by: Jason Gunthorpe <jgg@nvidia.com>
>
> Solves my splat too
>
> Let's send this to -rc please

Thank you for the testing. I will queue it for Joerg this week.

Best regards,
baolu