Commit 52a02554 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'irq-urgent-2022-02-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull irq fix from Thomas Gleixner:
 "A single fix for a regression caused by the recent PCI/MSI rework
  which resulted in a recursive locking problem in the VMD driver.

  The cure is to cache the relevant information upfront instead of
  retrieving it at runtime"

* tag 'irq-urgent-2022-02-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  PCI: vmd: Prevent recursive locking on interrupt allocation
parents 98f3e84f ba1366f3

drivers/pci/controller/vmd.c

+7 −7
Original line number Diff line number Diff line
@@ -99,11 +99,13 @@ struct vmd_irq { 
 * @srcu:	SRCU struct for local synchronization.

 * @count:	number of child IRQs assigned to this vector; used to track

 *		sharing.

 * @virq:	The underlying VMD Linux interrupt number

 */

struct vmd_irq_list {

	struct list_head	irq_list;

	struct srcu_struct	srcu;

	unsigned int		count;

	unsigned int		virq;

};



struct vmd_dev {
@@ -253,7 +255,6 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info, 
	struct msi_desc *desc = arg->desc;

	struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);

	struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);

	unsigned int index, vector;



	if (!vmdirq)

		return -ENOMEM;
@@ -261,10 +262,8 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info, 
	INIT_LIST_HEAD(&vmdirq->node);

	vmdirq->irq = vmd_next_irq(vmd, desc);

	vmdirq->virq = virq;

	index = index_from_irqs(vmd, vmdirq->irq);

	vector = pci_irq_vector(vmd->dev, index);



	irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,

	irq_domain_set_info(domain, virq, vmdirq->irq->virq, info->chip, vmdirq,

			    handle_untracked_irq, vmd, NULL);

	return 0;

}
@@ -685,7 +684,8 @@ static int vmd_alloc_irqs(struct vmd_dev *vmd) 
			return err;



		INIT_LIST_HEAD(&vmd->irqs[i].irq_list);

		err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),

		vmd->irqs[i].virq = pci_irq_vector(dev, i);

		err = devm_request_irq(&dev->dev, vmd->irqs[i].virq,

				       vmd_irq, IRQF_NO_THREAD,

				       vmd->name, &vmd->irqs[i]);

		if (err)
@@ -969,7 +969,7 @@ static int vmd_suspend(struct device *dev) 
	int i;



	for (i = 0; i < vmd->msix_count; i++)

		devm_free_irq(dev, pci_irq_vector(pdev, i), &vmd->irqs[i]);

		devm_free_irq(dev, vmd->irqs[i].virq, &vmd->irqs[i]);



	return 0;

}
@@ -981,7 +981,7 @@ static int vmd_resume(struct device *dev) 
	int err, i;



	for (i = 0; i < vmd->msix_count; i++) {

		err = devm_request_irq(dev, pci_irq_vector(pdev, i),

		err = devm_request_irq(dev, vmd->irqs[i].virq,

				       vmd_irq, IRQF_NO_THREAD,

				       vmd->name, &vmd->irqs[i]);

		if (err)