From ec154bf56b276a0bb36079a5d22a267b5f417801 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 6 Oct 2017 15:00:53 +0200 Subject: iommu/vt-d: Don't register bus-notifier under dmar_global_lock The notifier function will take the dmar_global_lock too, so lockdep complains about inverse locking order when the notifier is registered under the dmar_global_lock. Reported-by: Jan Kiszka Fixes: 59ce0515cdaf ('iommu/vt-d: Update DRHD/RMRR/ATSR device scope caches when PCI hotplug happens') Signed-off-by: Joerg Roedel --- drivers/iommu/dmar.c | 7 +++++-- drivers/iommu/intel-iommu.c | 10 ++++++++++ 2 files changed, 15 insertions(+), 2 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 57c920c1372d..1ea7cd537873 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -801,13 +801,16 @@ int __init dmar_dev_scope_init(void) dmar_free_pci_notify_info(info); } } - - bus_register_notifier(&pci_bus_type, &dmar_pci_bus_nb); } return dmar_dev_scope_status; } +void dmar_register_bus_notifier(void) +{ + bus_register_notifier(&pci_bus_type, &dmar_pci_bus_nb); +} + int __init dmar_table_init(void) { diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 6784a05dd6b2..934cef924461 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4752,6 +4752,16 @@ int __init intel_iommu_init(void) goto out_free_dmar; } + up_write(&dmar_global_lock); + + /* + * The bus notifier takes the dmar_global_lock, so lockdep will + * complain later when we register it under the lock. + */ + dmar_register_bus_notifier(); + + down_write(&dmar_global_lock); + if (no_iommu || dmar_disabled) { /* * We exit the function here to ensure IOMMU's remapping and -- cgit v1.2.3