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| author | Daniel Drake <drake@endlessm.com> | 2020-03-12 14:09:55 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-03-14 09:38:39 +0100 |
| commit | da72a379b2ec0bad3eb265787f7008bead0b040c (patch) | |
| tree | 51266964e9ceec405459006076261d05cb8088f7 /drivers/iommu | |
| parent | b0bb0c22c4db623f2e7b1a471596fbf1c22c6dc5 (diff) | |
| download | linux-da72a379b2ec0bad3eb265787f7008bead0b040c.tar.bz2 | |
iommu/vt-d: Ignore devices with out-of-spec domain number
VMD subdevices are created with a PCI domain ID of 0x10000 or
higher.
These subdevices are also handled like all other PCI devices by
dmar_pci_bus_notifier().
However, when dmar_alloc_pci_notify_info() take records of such devices,
it will truncate the domain ID to a u16 value (in info->seg).
The device at (e.g.) 10000:00:02.0 is then treated by the DMAR code as if
it is 0000:00:02.0.
In the unlucky event that a real device also exists at 0000:00:02.0 and
also has a device-specific entry in the DMAR table,
dmar_insert_dev_scope() will crash on:
BUG_ON(i >= devices_cnt);
That's basically a sanity check that only one PCI device matches a
single DMAR entry; in this case we seem to have two matching devices.
Fix this by ignoring devices that have a domain number higher than
what can be looked up in the DMAR table.
This problem was carefully diagnosed by Jian-Hong Pan.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Daniel Drake <drake@endlessm.com>
Fixes: 59ce0515cdaf3 ("iommu/vt-d: Update DRHD/RMRR/ATSR device scope caches when PCI hotplug happens")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/dmar.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index c7b1461e8d0a..f77dae7ba7d4 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -28,6 +28,7 @@ #include <linux/slab.h> #include <linux/iommu.h> #include <linux/numa.h> +#include <linux/limits.h> #include <asm/irq_remapping.h> #include <asm/iommu_table.h> @@ -128,6 +129,13 @@ dmar_alloc_pci_notify_info(struct pci_dev *dev, unsigned long event) BUG_ON(dev->is_virtfn); + /* + * Ignore devices that have a domain number higher than what can + * be looked up in DMAR, e.g. VMD subdevices with domain 0x10000 + */ + if (pci_domain_nr(dev->bus) > U16_MAX) + return NULL; + /* Only generate path[] for device addition event */ if (event == BUS_NOTIFY_ADD_DEVICE) for (tmp = dev; tmp; tmp = tmp->bus->self) |