From 0673b5b73c6ed8c2a6e08770d0b3d6ec0078cbf3 Mon Sep 17 00:00:00 2001 From: Jon Derrick Date: Tue, 21 Jul 2020 14:26:09 -0600 Subject: [PATCH] irqdomain/treewide: Free firmware node after domain removal commit ec0160891e387f4771f953b888b1fe951398e5d9 upstream. Commit 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode") unintentionally caused a dangling pointer page fault issue on firmware nodes that were freed after IRQ domain allocation. Commit e3beca48a45b fixed that dangling pointer issue by only freeing the firmware node after an IRQ domain allocation failure. That fix no longer frees the firmware node immediately, but leaves the firmware node allocated after the domain is removed. The firmware node must be kept around through irq_domain_remove, but should be freed it afterwards. Add the missing free operations after domain removal where where appropriate. Fixes: e3beca48a45b ("irqdomain/treewide: Keep firmware node unconditionally allocated") Signed-off-by: Jon Derrick Signed-off-by: Thomas Gleixner Reviewed-by: Andy Shevchenko Acked-by: Bjorn Helgaas # drivers/pci Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1595363169-7157-1-git-send-email-jonathan.derrick@intel.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/apic/io_apic.c | 5 +++++ drivers/iommu/intel_irq_remapping.c | 8 ++++++++ drivers/pci/host/vmd.c | 3 +++ 3 files changed, 16 insertions(+) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index b5652233e6745..a1c4a13782da8 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2252,8 +2252,13 @@ static int mp_irqdomain_create(int ioapic) static void ioapic_destroy_irqdomain(int idx) { + struct ioapic_domain_cfg *cfg = &ioapics[idx].irqdomain_cfg; + struct fwnode_handle *fn = ioapics[idx].irqdomain->fwnode; + if (ioapics[idx].irqdomain) { irq_domain_remove(ioapics[idx].irqdomain); + if (!cfg->dev) + irq_domain_free_fwnode(fn); ioapics[idx].irqdomain = NULL; } } diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 154949a499c21..7cc5b04e30b7a 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -601,13 +601,21 @@ out_free_table: static void intel_teardown_irq_remapping(struct intel_iommu *iommu) { + struct fwnode_handle *fn; + if (iommu && iommu->ir_table) { if (iommu->ir_msi_domain) { + fn = iommu->ir_msi_domain->fwnode; + irq_domain_remove(iommu->ir_msi_domain); + irq_domain_free_fwnode(fn); iommu->ir_msi_domain = NULL; } if (iommu->ir_domain) { + fn = iommu->ir_domain->fwnode; + irq_domain_remove(iommu->ir_domain); + irq_domain_free_fwnode(fn); iommu->ir_domain = NULL; } free_pages((unsigned long)iommu->ir_table->base, diff --git a/drivers/pci/host/vmd.c b/drivers/pci/host/vmd.c index 05f191ae0ff1b..79d56638878cf 100644 --- a/drivers/pci/host/vmd.c +++ b/drivers/pci/host/vmd.c @@ -651,6 +651,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd) if (!vmd->bus) { pci_free_resource_list(&resources); irq_domain_remove(vmd->irq_domain); + irq_domain_free_fwnode(fn); return -ENODEV; } @@ -753,6 +754,7 @@ static void vmd_cleanup_srcu(struct vmd_dev *vmd) static void vmd_remove(struct pci_dev *dev) { struct vmd_dev *vmd = pci_get_drvdata(dev); + struct fwnode_handle *fn = vmd->irq_domain->fwnode; sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); pci_stop_root_bus(vmd->bus); @@ -761,6 +763,7 @@ static void vmd_remove(struct pci_dev *dev) vmd_teardown_dma_ops(vmd); vmd_detach_resources(vmd); irq_domain_remove(vmd->irq_domain); + irq_domain_free_fwnode(fn); } #ifdef CONFIG_PM_SLEEP -- 2.47.3