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| author | Qian Cai <cai@lca.pw> | 2020-03-05 23:00:46 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-18 09:17:56 +0300 |
| commit | 4f60640723cfd989ac50550d3beb3538ca7a9bfa (patch) | |
| tree | 73a8895523ce8174a4e4dbeb429bb48897fa5c87 /drivers/iommu | |
| parent | b8c3cbca80e86c703ecf8aea629cbac9399837a7 (diff) | |
| download | linux-4f60640723cfd989ac50550d3beb3538ca7a9bfa.tar.xz | |
iommu/vt-d: Fix RCU-list bugs in intel_iommu_init()
commit 2d48ea0efb8887ebba3e3720bb5b738aced4e574 upstream.
There are several places traverse RCU-list without holding any lock in
intel_iommu_init(). Fix them by acquiring dmar_global_lock.
WARNING: suspicious RCU usage
-----------------------------
drivers/iommu/intel-iommu.c:5216 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by swapper/0/1.
Call Trace:
dump_stack+0xa0/0xea
lockdep_rcu_suspicious+0x102/0x10b
intel_iommu_init+0x947/0xb13
pci_iommu_init+0x26/0x62
do_one_initcall+0xfe/0x500
kernel_init_freeable+0x45a/0x4f8
kernel_init+0x11/0x139
ret_from_fork+0x3a/0x50
DMAR: Intel(R) Virtualization Technology for Directed I/O
Fixes: d8190dc63886 ("iommu/vt-d: Enable DMA remapping after rmrr mapped")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 90f5b0e4effc..1c2b3e78056f 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -5024,6 +5024,7 @@ int __init intel_iommu_init(void) init_iommu_pm_ops(); + down_read(&dmar_global_lock); for_each_active_iommu(iommu, drhd) { iommu_device_sysfs_add(&iommu->iommu, NULL, intel_iommu_groups, @@ -5031,6 +5032,7 @@ int __init intel_iommu_init(void) iommu_device_set_ops(&iommu->iommu, &intel_iommu_ops); iommu_device_register(&iommu->iommu); } + up_read(&dmar_global_lock); bus_set_iommu(&pci_bus_type, &intel_iommu_ops); if (si_domain && !hw_pass_through) @@ -5041,7 +5043,6 @@ int __init intel_iommu_init(void) down_read(&dmar_global_lock); if (probe_acpi_namespace_devices()) pr_warn("ACPI name space devices didn't probe correctly\n"); - up_read(&dmar_global_lock); /* Finally, we enable the DMA remapping hardware. */ for_each_iommu(iommu, drhd) { @@ -5050,6 +5051,8 @@ int __init intel_iommu_init(void) iommu_disable_protect_mem_regions(iommu); } + up_read(&dmar_global_lock); + pr_info("Intel(R) Virtualization Technology for Directed I/O\n"); intel_iommu_enabled = 1; |