The struct iommu_device has a 'struct device' embedded into
it, not as a pointer, but the whole struct. In the
conversion of the iommu drivers to use struct iommu_device
it was forgotten that the relase function for that struct
device simply calls kfree() on the pointer.
This frees memory that was never allocated and causes memory
corruption.
To fix this issue, use a pointer to struct device instead of
embedding the whole struct. This needs some updates in the
iommu sysfs code as well as the Intel VT-d and AMD IOMMU
driver.
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Fixes: 39ab9555c2 ('iommu: Add sysfs bindings for struct iommu_device')
Cc: stable@vger.kernel.org # >= v4.11
Signed-off-by: Joerg Roedel <jroedel@suse.de>
There is currently support for iommu sysfs bindings, but
those need to be implemented in the IOMMU drivers. Add a
more generic version of this by adding a struct device to
struct iommu_device and use that for the sysfs bindings.
Also convert the AMD and Intel IOMMU driver to make use of
it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
IOMMUs currently have no common representation to userspace, most
seem to have no representation at all aside from a few printks
on bootup. There are however features of IOMMUs that are useful
to know about. For instance the IOMMU might support superpages,
making use of processor large/huge pages more important in a device
assignment scenario. It's also useful to create cross links between
devices and IOMMU hardware units, so that users might be able to
load balance their devices to avoid thrashing a single hardware unit.
This patch adds a device create and destroy interface as well as
device linking, making it very lightweight for an IOMMU driver to add
basic support. IOMMU drivers can provide additional attributes
automatically by using an attribute_group.
The attributes exposed are expected to be relatively device specific,
the means to retrieve them certainly are, so there are currently no
common attributes for the new class created here.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
