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authorLu Baolu <baolu.lu@linux.intel.com>2022-09-21 05:40:53 +0300
committerJoerg Roedel <jroedel@suse.de>2022-09-21 11:22:54 +0300
commit7ebb5f8e001037efbdf18afabbbebf71bd98825e (patch)
tree2c3f16e6e9c0ca0b207d12c8f6a0627c2ea35371 /drivers
parent521a547ced6477c54b4b0cc206000406c221b4d6 (diff)
downloadlinux-7ebb5f8e001037efbdf18afabbbebf71bd98825e.tar.xz
Revert "iommu/vt-d: Fix possible recursive locking in intel_iommu_init()"
This reverts commit 9cd4f1434479f1ac25c440c421fbf52069079914. Some issues were reported on the original commit. Some thunderbolt devices don't work anymore due to the following DMA fault. DMAR: DRHD: handling fault status reg 2 DMAR: [INTR-REMAP] Request device [09:00.0] fault index 0x8080 [fault reason 0x25] Blocked a compatibility format interrupt request Bring it back for now to avoid functional regression. Fixes: 9cd4f1434479f ("iommu/vt-d: Fix possible recursive locking in intel_iommu_init()") Link: https://lore.kernel.org/linux-iommu/485A6EA5-6D58-42EA-B298-8571E97422DE@getmailspring.com/ Link: https://bugzilla.kernel.org/show_bug.cgi?id=216497 Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: <stable@vger.kernel.org> # 5.19.x Reported-and-tested-by: George Hilliard <thirtythreeforty@gmail.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20220920081701.3453504-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/iommu/intel/dmar.c7
-rw-r--r--drivers/iommu/intel/iommu.c27
2 files changed, 25 insertions, 9 deletions
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 497c912ad9e1..5a8f780e7ffd 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -2349,13 +2349,6 @@ static int dmar_device_hotplug(acpi_handle handle, bool insert)
if (!dmar_in_use())
return 0;
- /*
- * It's unlikely that any I/O board is hot added before the IOMMU
- * subsystem is initialized.
- */
- if (IS_ENABLED(CONFIG_INTEL_IOMMU) && !intel_iommu_enabled)
- return -EOPNOTSUPP;
-
if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) {
tmp = handle;
} else {
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 1f2cd43cf9bc..64d30895a4c8 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -3019,7 +3019,13 @@ static int __init init_dmars(void)
#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_supported(iommu) && ecap_prs(iommu->ecap)) {
+ /*
+ * Call dmar_alloc_hwirq() with dmar_global_lock held,
+ * could cause possible lock race condition.
+ */
+ up_write(&dmar_global_lock);
ret = intel_svm_enable_prq(iommu);
+ down_write(&dmar_global_lock);
if (ret)
goto free_iommu;
}
@@ -3932,6 +3938,7 @@ int __init intel_iommu_init(void)
force_on = (!intel_iommu_tboot_noforce && tboot_force_iommu()) ||
platform_optin_force_iommu();
+ down_write(&dmar_global_lock);
if (dmar_table_init()) {
if (force_on)
panic("tboot: Failed to initialize DMAR table\n");
@@ -3944,6 +3951,16 @@ 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)
intel_iommu_debugfs_init();
@@ -3988,9 +4005,11 @@ int __init intel_iommu_init(void)
pr_err("Initialization failed\n");
goto out_free_dmar;
}
+ up_write(&dmar_global_lock);
init_iommu_pm_ops();
+ down_read(&dmar_global_lock);
for_each_active_iommu(iommu, drhd) {
/*
* The flush queue implementation does not perform
@@ -4008,11 +4027,13 @@ int __init intel_iommu_init(void)
"%s", iommu->name);
iommu_device_register(&iommu->iommu, &intel_iommu_ops, NULL);
}
+ up_read(&dmar_global_lock);
bus_set_iommu(&pci_bus_type, &intel_iommu_ops);
if (si_domain && !hw_pass_through)
register_memory_notifier(&intel_iommu_memory_nb);
+ down_read(&dmar_global_lock);
if (probe_acpi_namespace_devices())
pr_warn("ACPI name space devices didn't probe correctly\n");
@@ -4023,15 +4044,17 @@ int __init intel_iommu_init(void)
iommu_disable_protect_mem_regions(iommu);
}
+ up_read(&dmar_global_lock);
- intel_iommu_enabled = 1;
- dmar_register_bus_notifier();
pr_info("Intel(R) Virtualization Technology for Directed I/O\n");
+ intel_iommu_enabled = 1;
+
return 0;
out_free_dmar:
intel_iommu_free_dmars();
+ up_write(&dmar_global_lock);
return ret;
}