From: Jon Derrick jonathan.derrick@intel.com
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 jonathan.derrick@intel.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Acked-by: Bjorn Helgaas bhelgaas@google.com # drivers/pci Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1595363169-7157-1-git-send-email-jonathan.derrick@... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kernel/apic/io_apic.c | 5 +++++ drivers/iommu/intel_irq_remapping.c | 8 ++++++++ drivers/pci/controller/vmd.c | 3 +++ 3 files changed, 16 insertions(+)
--- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2342,8 +2342,13 @@ static int mp_irqdomain_create(int ioapi
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; } } --- 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, --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -718,6 +718,7 @@ static int vmd_enable_domain(struct vmd_ if (!vmd->bus) { pci_free_resource_list(&resources); irq_domain_remove(vmd->irq_domain); + irq_domain_free_fwnode(fn); return -ENODEV; }
@@ -820,6 +821,7 @@ static void vmd_cleanup_srcu(struct 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); @@ -828,6 +830,7 @@ static void vmd_remove(struct pci_dev *d vmd_teardown_dma_ops(vmd); vmd_detach_resources(vmd); irq_domain_remove(vmd->irq_domain); + irq_domain_free_fwnode(fn); }
#ifdef CONFIG_PM_SLEEP