From 49c4959f04b587c8909b33adca4066995c768d60 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Wed, 14 Jul 2021 14:57:19 -0700 Subject: [PATCH] dmaengine: idxd: fix sequence for pci driver remove() and shutdown() ->shutdown() call should only be responsible for quiescing the device. Currently it is doing PCI device tear down. This causes issue when things like MMIO mapping is removed while idxd_unregister_devices() will trigger removal of idxd device sub-driver and still initiates MMIO writes to the device. Another issue is with the unregistering of idxd 'struct device', the memory context gets freed. So the teardown calls are accessing freed memory and can cause kernel oops. Move all the teardown bits that doesn't belong in shutdown to ->remove() call. Move unregistering of the idxd conf_dev 'struct device' to after doing all the teardown to free all the memory that's no longer needed. Fixes: 47c16ac27d4c ("dmaengine: idxd: fix idxd conf_dev 'struct device' lifetime") Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/162629983901.395844.17964803190905549615.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul --- drivers/dma/idxd/init.c | 26 +++++++++++++++++--------- drivers/dma/idxd/sysfs.c | 2 -- 2 files changed, 17 insertions(+), 11 deletions(-) diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 7eac0d167bde6..75ac6a4bc9d1a 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -754,32 +754,40 @@ static void idxd_shutdown(struct pci_dev *pdev) for (i = 0; i < msixcnt; i++) { irq_entry = &idxd->irq_entries[i]; synchronize_irq(irq_entry->vector); - free_irq(irq_entry->vector, irq_entry); if (i == 0) continue; idxd_flush_pending_llist(irq_entry); idxd_flush_work_list(irq_entry); } - - idxd_msix_perm_clear(idxd); - idxd_release_int_handles(idxd); - pci_free_irq_vectors(pdev); - pci_iounmap(pdev, idxd->reg_base); - pci_disable_device(pdev); - destroy_workqueue(idxd->wq); + flush_workqueue(idxd->wq); } static void idxd_remove(struct pci_dev *pdev) { struct idxd_device *idxd = pci_get_drvdata(pdev); + struct idxd_irq_entry *irq_entry; + int msixcnt = pci_msix_vec_count(pdev); + int i; dev_dbg(&pdev->dev, "%s called\n", __func__); idxd_shutdown(pdev); if (device_pasid_enabled(idxd)) idxd_disable_system_pasid(idxd); idxd_unregister_devices(idxd); - perfmon_pmu_remove(idxd); + + for (i = 0; i < msixcnt; i++) { + irq_entry = &idxd->irq_entries[i]; + free_irq(irq_entry->vector, irq_entry); + } + idxd_msix_perm_clear(idxd); + idxd_release_int_handles(idxd); + pci_free_irq_vectors(pdev); + pci_iounmap(pdev, idxd->reg_base); iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA); + pci_disable_device(pdev); + destroy_workqueue(idxd->wq); + perfmon_pmu_remove(idxd); + device_unregister(&idxd->conf_dev); } static struct pci_driver idxd_pci_driver = { diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c index a193de32536d1..33c27df40f1e8 100644 --- a/drivers/dma/idxd/sysfs.c +++ b/drivers/dma/idxd/sysfs.c @@ -1751,8 +1751,6 @@ void idxd_unregister_devices(struct idxd_device *idxd) device_unregister(&group->conf_dev); } - - device_unregister(&idxd->conf_dev); } int idxd_register_bus_type(void) -- 2.30.2