Pull iommufd updates from Jason Gunthorpe:
"On top of the vfio updates is built some new iommufd functionality:
- IOMMU_HWPT_ALLOC allows userspace to directly create the low level
IO Page table objects and affiliate them with IOAS objects that
hold the translation mapping. This is the basic functionality for
the normal IOMMU_DOMAIN_PAGING domains.
- VFIO_DEVICE_ATTACH_IOMMUFD_PT can be used to replace the current
translation. This is wired up to through all the layers down to the
driver so the driver has the ability to implement a hitless
replacement. This is necessary to fully support guest behaviors
when emulating HW (eg guest atomic change of translation)
- IOMMU_GET_HW_INFO returns information about the IOMMU driver HW
that owns a VFIO device. This includes support for the Intel iommu,
and patches have been posted for all the other server IOMMU.
Along the way are a number of internal items:
- New iommufd kernel APIs: iommufd_ctx_has_group(),
iommufd_device_to_ictx(), iommufd_device_to_id(),
iommufd_access_detach(), iommufd_ctx_from_fd(),
iommufd_device_replace()
- iommufd now internally tracks iommu_groups as it needs some
per-group data
- Reorganize how the internal hwpt allocation flows to have more
robust locking
- Improve the access interfaces to support detach and replace of an
IOAS from an access
- New selftests and a rework of how the selftests creates a mock
iommu driver to be more like a real iommu driver"
Link: https://lore.kernel.org/lkml/ZO%2FTe6LU1ENf58ZW@nvidia.com/
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (34 commits)
iommufd/selftest: Don't leak the platform device memory when unloading the module
iommu/vt-d: Implement hw_info for iommu capability query
iommufd/selftest: Add coverage for IOMMU_GET_HW_INFO ioctl
iommufd: Add IOMMU_GET_HW_INFO
iommu: Add new iommu op to get iommu hardware information
iommu: Move dev_iommu_ops() to private header
iommufd: Remove iommufd_ref_to_users()
iommufd/selftest: Make the mock iommu driver into a real driver
vfio: Support IO page table replacement
iommufd/selftest: Add IOMMU_TEST_OP_ACCESS_REPLACE_IOAS coverage
iommufd: Add iommufd_access_replace() API
iommufd: Use iommufd_access_change_ioas in iommufd_access_destroy_object
iommufd: Add iommufd_access_change_ioas(_id) helpers
iommufd: Allow passing in iopt_access_list_id to iopt_remove_access()
vfio: Do not allow !ops->dma_unmap in vfio_pin/unpin_pages()
iommufd/selftest: Add a selftest for IOMMU_HWPT_ALLOC
iommufd/selftest: Return the real idev id from selftest mock_domain
iommufd: Add IOMMU_HWPT_ALLOC
iommufd/selftest: Test iommufd_device_replace()
iommufd: Make destroy_rwsem use a lock class per object type
...
Pull VFIO updates from Alex Williamson: - VFIO direct character device (cdev) interface support. This extracts the vfio device fd from the container and group model, and is intended to be the native uAPI for use with IOMMUFD (Yi Liu) - Enhancements to the PCI hot reset interface in support of cdev usage (Yi Liu) - Fix a potential race between registering and unregistering vfio files in the kvm-vfio interface and extend use of a lock to avoid extra drop and acquires (Dmitry Torokhov) - A new vfio-pci variant driver for the AMD/Pensando Distributed Services Card (PDS) Ethernet device, supporting live migration (Brett Creeley) - Cleanups to remove redundant owner setup in cdx and fsl bus drivers, and simplify driver init/exit in fsl code (Li Zetao) - Fix uninitialized hole in data structure and pad capability structures for alignment (Stefan Hajnoczi) * tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio: (53 commits) vfio/pds: Send type for SUSPEND_STATUS command vfio/pds: fix return value in pds_vfio_get_lm_file() pds_core: Fix function header descriptions vfio: align capability structures vfio/type1: fix cap_migration information leak vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver vfio/pds: Add Kconfig and documentation vfio/pds: Add support for firmware recovery vfio/pds: Add support for dirty page tracking vfio/pds: Add VFIO live migration support vfio/pds: register with the pds_core PF pds_core: Require callers of register/unregister to pass PF drvdata vfio/pds: Initial support for pds VFIO driver vfio: Commonize combine_ranges for use in other VFIO drivers kvm/vfio: avoid bouncing the mutex when adding and deleting groups kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add() docs: vfio: Add vfio device cdev description vfio: Compile vfio_group infrastructure optionally vfio: Move the IOMMU_CAP_CACHE_COHERENCY check in __vfio_register_dev() ...
Commit bb500dbe2ac6 ("vfio/pds: Add VFIO live migration support")
added live migration support for the pds-vfio-pci driver. When
sending the SUSPEND command to the device, the driver sets the
type of suspend (i.e. P2P or FULL). However, the driver isn't
sending the type of suspend for the SUSPEND_STATUS command, which
will result in failures. Fix this by also sending the suspend type
in the SUSPEND_STATUS command.
Fixes: bb500dbe2ac6 ("vfio/pds: Add VFIO live migration support")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230821184215.34564-1-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
anon_inode_getfile() never returns NULL pointer, it will return
ERR_PTR() when it fails, so replace the check with IS_ERR().
Fixes: bb500dbe2ac6 ("vfio/pds: Add VFIO live migration support")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://lore.kernel.org/r/20230819023716.3469037-1-yangyingliang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The VFIO_DEVICE_GET_INFO, VFIO_DEVICE_GET_REGION_INFO, and VFIO_IOMMU_GET_INFO ioctls fill in an info struct followed by capability structs: +------+---------+---------+-----+ | info | caps[0] | caps[1] | ... | +------+---------+---------+-----+ Both the info and capability struct sizes are not always multiples of sizeof(u64), leaving u64 fields in later capability structs misaligned. Userspace applications currently need to handle misalignment manually in order to support CPU architectures and programming languages with strict alignment requirements. Make life easier for userspace by ensuring alignment in the kernel. This is done by padding info struct definitions and by copying out zeroes after capability structs that are not aligned. The new layout is as follows: +------+---------+---+---------+-----+ | info | caps[0] | 0 | caps[1] | ... | +------+---------+---+---------+-----+ In this example caps[0] has a size that is not multiples of sizeof(u64), so zero padding is added to align the subsequent structure. Adding zero padding between structs does not break the uapi. The memory layout is specified by the info.cap_offset and caps[i].next fields filled in by the kernel. Applications use these field values to locate structs and are therefore unaffected by the addition of zero padding. Note that code that copies out info structs with padding is updated to always zero the struct and copy out as many bytes as userspace requested. This makes the code shorter and avoids potential information leaks by ensuring padding is initialized. Originally-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230809203144.2880050-1-stefanha@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Fix an information leak where an uninitialized hole in struct
vfio_iommu_type1_info_cap_migration on the stack is exposed to userspace.
The definition of struct vfio_iommu_type1_info_cap_migration contains a hole as
shown in this pahole(1) output:
struct vfio_iommu_type1_info_cap_migration {
struct vfio_info_cap_header header; /* 0 8 */
__u32 flags; /* 8 4 */
/* XXX 4 bytes hole, try to pack */
__u64 pgsize_bitmap; /* 16 8 */
__u64 max_dirty_bitmap_size; /* 24 8 */
/* size: 32, cachelines: 1, members: 4 */
/* sum members: 28, holes: 1, sum holes: 4 */
/* last cacheline: 32 bytes */
};
The cap_mig variable is filled in without initializing the hole:
static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
struct vfio_info_cap *caps)
{
struct vfio_iommu_type1_info_cap_migration cap_mig;
cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
cap_mig.header.version = 1;
cap_mig.flags = 0;
/* support minimum pgsize */
cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;
return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
}
The structure is then copied to a temporary location on the heap. At this point
it's already too late and ioctl(VFIO_IOMMU_GET_INFO) copies it to userspace
later:
int vfio_info_add_capability(struct vfio_info_cap *caps,
struct vfio_info_cap_header *cap, size_t size)
{
struct vfio_info_cap_header *header;
header = vfio_info_cap_add(caps, size, cap->id, cap->version);
if (IS_ERR(header))
return PTR_ERR(header);
memcpy(header + 1, cap + 1, size - sizeof(*header));
return 0;
}
This issue was found by code inspection.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Fixes: ad721705d09c ("vfio iommu: Add migration capability to report supported features")
Link: https://lore.kernel.org/r/20230801155352.1391945-1-stefanha@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Use the module_fsl_mc_driver macro to simplify the code and remove redundant initialization owner in vfio_fsl_mc_driver. Signed-off-by: Li Zetao <lizetao1@huawei.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230809131536.4021639-1-lizetao1@huawei.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The cdx_driver_register() will set "THIS_MODULE" to driver.owner when register a cdx_driver driver, so it is redundant initialization to set driver.owner in the statement. Remove it for clean code. Signed-off-by: Li Zetao <lizetao1@huawei.com> Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com> Link: https://lore.kernel.org/r/20230808020937.2975196-1-lizetao1@huawei.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add Kconfig entries and pds-vfio-pci.rst. Also, add an entry in the MAINTAINERS file for this new driver. It's not clear where documentation for vendor specific VFIO drivers should live, so just re-use the current amd ethernet location. Signed-off-by: Brett Creeley <brett.creeley@amd.com> Signed-off-by: Shannon Nelson <shannon.nelson@amd.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230807205755.29579-9-brett.creeley@amd.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
It's possible that the device firmware crashes and is able to recover due to some configuration and/or other issue. If a live migration is in progress while the firmware crashes, the live migration will fail. However, the VF PCI device should still be functional post crash recovery and subsequent migrations should go through as expected. When the pds_core device notices that firmware crashes it sends an event to all its client drivers. When the pds_vfio driver receives this event while migration is in progress it will request a deferred reset on the next migration state transition. This state transition will report failure as well as any subsequent state transition requests from the VMM/VFIO. Based on uapi/vfio.h the only way out of VFIO_DEVICE_STATE_ERROR is by issuing VFIO_DEVICE_RESET. Once this reset is done, the migration state will be reset to VFIO_DEVICE_STATE_RUNNING and migration can be performed. If the event is received while no migration is in progress (i.e. the VM is in normal operating mode), then no actions are taken and the migration state remains VFIO_DEVICE_STATE_RUNNING. Signed-off-by: Brett Creeley <brett.creeley@amd.com> Signed-off-by: Shannon Nelson <shannon.nelson@amd.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230807205755.29579-8-brett.creeley@amd.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>