On Sat, Aug 02, 2025 at 07:47:02PM -0700, Chaitanya Kulkarni wrote:
> Add foundational infrastructure for vfio-nvme, enabling support for live
> migration of NVMe devices via the VFIO framework. The following
> components are included:
> +static void nvmevf_pci_aer_reset_done(struct pci_dev *pdev)
> +{
> + struct nvmevf_pci_core_device *nvmevf_dev = nvmevf_drvdata(pdev);
> +
> + if (!nvmevf_dev->migrate_cap)
> + return;
> +
> + /*
> + * As the higher VFIO layers are holding locks across reset and using
> + * those same locks with the mm_lock we need to prevent ABBA deadlock
> + * with the state_mutex and mm_lock.
Add blank line between paragraphs.
> + * In case the state_mutex was taken already we defer the cleanup work
> + * to the unlock flow of the other running context.
> + */
> + spin_lock(&nvmevf_dev->reset_lock);
> + nvmevf_dev->deferred_reset = true;
> + if (!mutex_trylock(&nvmevf_dev->state_mutex)) {
> + spin_unlock(&nvmevf_dev->reset_lock);
> + return;
> + }
> + spin_unlock(&nvmevf_dev->reset_lock);
> + nvmevf_state_mutex_unlock(nvmevf_dev);
> +}
