Re: [PATCH 1/1] iommu/vt-d: Fix possible recursive lock in iommu_flush_dev_iotlb()

[Baolu Lu]

On 2022/8/17 10:56, Lu Baolu wrote:
> The per domain spinlock is acquired in iommu_flush_dev_iotlb(), which
> is possbile to be called in the interrupt context. For instance,
>
>    <IRQ>
>    iommu_flush_dev_iotlb
>    iommu_flush_iotlb_psi
>    intel_iommu_tlb_sync
>    iommu_iotlb_sync
>    __iommu_dma_unmap
>    ? nvme_unmap_data
>    nvme_unmap_data
>    nvme_pci_complete_rq
>    nvme_irq
>    __handle_irq_event_percpu
>    handle_irq_event_percpu
>    handle_irq_event
>    handle_edge_irq
>    __common_interrupt
>    common_interrupt
>
> This coverts the spin_lock/unlock() into the irq save/restore varieties
> to avoid the possible recursive locking issues.
>
> Fixes: ffd5869d93530 ("iommu/vt-d: Replace spin_lock_irqsave() with spin_lock()")
> Signed-off-by: Lu Baolu<baolu.lu@xxxxxxxxxxxxxxx>

This patch has been queued:

https://lore.kernel.org/linux-iommu/20220823061557.1631056-1-baolu.lu@xxxxxxxxxxxxxxx/

Best regards,
baolu