From c49ae619905eebd3f54598a84e4cd2bd58ba8fe9 Mon Sep 17 00:00:00 2001 From: Pali Rohár Date: Mon, 14 Feb 2022 12:02:28 +0100 Subject: PCI: mvebu: Fix device enumeration regression MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Jan reported that on Turris Omnia (Armada 385), no PCIe devices were detected after upgrading from v5.16.1 to v5.16.3 and identified the cause as the backport of 91a8d79fc797 ("PCI: mvebu: Fix configuring secondary bus of PCIe Root Port via emulated bridge"), which appeared in v5.17-rc1. 91a8d79fc797 was incorrectly applied from mailing list patch [1] to the linux git repository [2] probably due to resolving merge conflicts incorrectly. Fix it now. [1] https://lore.kernel.org/r/20211125124605.25915-12-pali@kernel.org [2] https://git.kernel.org/linus/91a8d79fc797 [bhelgaas: commit log] BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215540 Fixes: 91a8d79fc797 ("PCI: mvebu: Fix configuring secondary bus of PCIe Root Port via emulated bridge") Link: https://lore.kernel.org/r/20220214110228.25825-1-pali@kernel.org Link: https://lore.kernel.org/r/20220127234917.GA150851@bhelgaas Reported-by: Jan Palus Signed-off-by: Pali Rohár Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/pci-mvebu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/pci/controller') diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index 71258ea3d35f..f8e82c5e2d87 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -1329,7 +1329,8 @@ static int mvebu_pcie_probe(struct platform_device *pdev) * indirectly via kernel emulated PCI bridge driver. */ mvebu_pcie_setup_hw(port); - mvebu_pcie_set_local_dev_nr(port, 0); + mvebu_pcie_set_local_dev_nr(port, 1); + mvebu_pcie_set_local_bus_nr(port, 0); } pcie->nports = i; -- cgit v1.2.3-70-g09d2 From ba1366f3d039e7c3ca1fc29ed00ce3ed2b8fd32f Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 13 Feb 2022 14:54:05 +0100 Subject: PCI: vmd: Prevent recursive locking on interrupt allocation Tejas reported the following recursive locking issue: swapper/0/1 is trying to acquire lock: ffff8881074fd0a0 (&md->mutex){+.+.}-{3:3}, at: msi_get_virq+0x30/0xc0 but task is already holding lock: ffff8881017cd6a0 (&md->mutex){+.+.}-{3:3}, at: __pci_enable_msi_range+0xf2/0x290 stack backtrace: __mutex_lock+0x9d/0x920 msi_get_virq+0x30/0xc0 pci_irq_vector+0x26/0x30 vmd_msi_init+0xcc/0x210 msi_domain_alloc+0xbf/0x150 msi_domain_alloc_irqs_descs_locked+0x3e/0xb0 __pci_enable_msi_range+0x155/0x290 pci_alloc_irq_vectors_affinity+0xba/0x100 pcie_port_device_register+0x307/0x550 pcie_portdrv_probe+0x3c/0xd0 pci_device_probe+0x95/0x110 This is caused by the VMD MSI code which does a lookup of the Linux interrupt number for an VMD managed MSI[X] vector. The lookup function tries to acquire the already held mutex. Avoid that by caching the Linux interrupt number at initialization time instead of looking it up over and over. Fixes: 82ff8e6b78fc ("PCI/MSI: Use msi_get_virq() in pci_get_vector()") Reported-by: "Surendrakumar Upadhyay, TejaskumarX" Signed-off-by: Thomas Gleixner Tested-by: "Surendrakumar Upadhyay, TejaskumarX" Cc: linux-pci@vger.kernel.org Link: https://lore.kernel.org/r/87a6euub2a.ffs@tglx --- drivers/pci/controller/vmd.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/pci/controller') diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index cc166c683638..eb05cceab964 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -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) -- cgit v1.2.3-70-g09d2