Function device_notifier() in intel-iommu.c only remove domain_device_info data structure associated with a PCI device when handling PCI device driver unbinding events. If a PCI device has never been bound to a PCI device driver, there won't be BUS_NOTIFY_UNBOUND_DRIVER event when hot-removing the PCI device. So associated domain_device_info data structure may get lost.
On the other hand, if iommu_pass_through is enabled, function iommu_prepare_static_indentify_mapping() will create domain_device_info data structure for each PCIe to PCIe bridge and PCIe endpoint, no matter whether there are drivers associated with those PCIe devices or not. So those domain_device_info data structures will get lost when hot-removing the assocated PCIe devices if they have never bound to any PCI device driver. To be even worse, it's not only an memory leak issue, but also an caching of stale information bug because the memory are kept in device_domain_list and domain->devices lists. Fix the bug by trying to remove domain_device_info data structure when handling BUS_NOTIFY_DEL_DEVICE event. Signed-off-by: Jiang Liu <jiang....@linux.intel.com> --- drivers/iommu/intel-iommu.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index f75d3ae..5a411e8 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3603,18 +3603,19 @@ static int device_notifier(struct notifier_block *nb, if (iommu_dummy(pdev)) return 0; + if (action != BUS_NOTIFY_UNBOUND_DRIVER && + action != BUS_NOTIFY_DEL_DEVICE) + return 0; + domain = find_domain(pdev); if (!domain) return 0; - if (action == BUS_NOTIFY_UNBOUND_DRIVER) { - domain_remove_one_dev_info(domain, pdev); - - if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) && - !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) && - list_empty(&domain->devices)) - domain_exit(domain); - } + domain_remove_one_dev_info(domain, pdev); + if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) && + !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) && + list_empty(&domain->devices)) + domain_exit(domain); return 0; } -- 1.7.10.4 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu