The mtty driver exposes a PCI serial device to userspace and therefore
makes an easy target for a sample device supporting migration. The device
does not make use of DMA, therefore we can easily claim support for the
migration P2P states, as well as dirty logging. This implementation also
makes use of PRE_COPY support in order to provide migration stream
compatibility testing, which should generally be considered good practice.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20231016224736.2575718-3-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The mtty driver does not currently conform to the vfio SET_IRQS uAPI.
For example, it claims to support mask and unmask of INTx, but actually
does nothing. It claims to support AUTOMASK for INTx, but doesn't. It
fails to teardown eventfds under the full semantics specified by the
SET_IRQS ioctl. It also fails to teardown eventfds when the device is
closed, leading to memory leaks. It claims to support the request IRQ,
but doesn't.
Fix all these.
A side effect of this is that QEMU will now report a warning:
vfio <uuid>: Failed to set up UNMASK eventfd signaling for interrupt \
INTX-0: VFIO_DEVICE_SET_IRQS failure: Inappropriate ioctl for device
The fact is that the unmask eventfd was never supported but quietly
failed. mtty never honored the AUTOMASK behavior, therefore there
was nothing to unmask. QEMU is verbose about the failure, but
properly falls back to userspace unmasking.
Fixes: 9d1a546c53 ("docs: Sample driver to demonstrate how to use Mediated device framework.")
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20231016224736.2575718-2-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The memory layout of struct vfio_device_gfx_plane_info is
architecture-dependent due to a u64 field and a struct size that is not
a multiple of 8 bytes:
- On x86_64 the struct size is padded to a multiple of 8 bytes.
- On x32 the struct size is only a multiple of 4 bytes, not 8.
- Other architectures may vary.
Use __aligned_u64 to make memory layout consistent. This reduces the
chance of 32-bit userspace on a 64-bit kernel breakage.
This patch increases the struct size on x32 but this is safe because of
the struct's argsz field. The kernel may grow the struct as long as it
still supports smaller argsz values from userspace (e.g. applications
compiled against older kernel headers).
Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://lore.kernel.org/r/20230918205617.1478722-3-stefanha@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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()
...
Set struct fb_ops and with FB_DEFAULT_IOMEM_OPS, fbdev's initializer
for I/O memory. Sets the callbacks to the cfb_ and fb_io_ functions.
Select the correct modules with Kconfig's FB_IOMEM_HELPERS token.
The macro and token set the currently selected values, so there is
no functional change.
v3:
* use _IOMEM_ in commit message
v2:
* updated to use _IOMEM_ tokens
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230803184034.6456-48-tzimmermann@suse.de
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening
in the driver core in the quest to be able to move "struct bus" and
"struct class" into read-only memory, a task now complete with these
changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules
for all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most
of them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
device property: make device_property functions take const device *
driver core: update comments in device_rename()
driver core: Don't require dynamic_debug for initcall_debug probe timing
firmware_loader: rework crypto dependencies
firmware_loader: Strip off \n from customized path
zram: fix up permission for the hot_add sysfs file
cacheinfo: Add use_arch[|_cache]_info field/function
arch_topology: Remove early cacheinfo error message if -ENOENT
cacheinfo: Check cache properties are present in DT
cacheinfo: Check sib_leaf in cache_leaves_are_shared()
cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
cacheinfo: Add arm64 early level initializer implementation
cacheinfo: Add arch specific early level initializer
tty: make tty_class a static const structure
driver core: class: remove struct class_interface * from callbacks
driver core: class: mark the struct class in struct class_interface constant
driver core: class: make class_register() take a const *
driver core: class: mark class_release() as taking a const *
driver core: remove incorrect comment for device_create*
MIPS: vpe-cmp: remove module owner pointer from struct class usage.
...
Pull VFIO updates from Alex Williamson:
- Remove redundant resource check in vfio-platform (Angus Chen)
- Use GFP_KERNEL_ACCOUNT for persistent userspace allocations, allowing
removal of arbitrary kernel limits in favor of cgroup control (Yishai
Hadas)
- mdev tidy-ups, including removing the module-only build restriction
for sample drivers, Kconfig changes to select mdev support,
documentation movement to keep sample driver usage instructions with
sample drivers rather than with API docs, remove references to
out-of-tree drivers in docs (Christoph Hellwig)
- Fix collateral breakages from mdev Kconfig changes (Arnd Bergmann)
- Make mlx5 migration support match device support, improve source and
target flows to improve pre-copy support and reduce downtime (Yishai
Hadas)
- Convert additional mdev sysfs case to use sysfs_emit() (Bo Liu)
- Resolve copy-paste error in mdev mbochs sample driver Kconfig (Ye
Xingchen)
- Avoid propagating missing reset error in vfio-platform if reset
requirement is relaxed by module option (Tomasz Duszynski)
- Range size fixes in mlx5 variant driver for missed last byte and
stricter range calculation (Yishai Hadas)
- Fixes to suspended vaddr support and locked_vm accounting, excluding
mdev configurations from the former due to potential to indefinitely
block kernel threads, fix underflow and restore locked_vm on new mm
(Steve Sistare)
- Update outdated vfio documentation due to new IOMMUFD interfaces in
recent kernels (Yi Liu)
- Resolve deadlock between group_lock and kvm_lock, finally (Matthew
Rosato)
- Fix NULL pointer in group initialization error path with IOMMUFD (Yan
Zhao)
* tag 'vfio-v6.3-rc1' of https://github.com/awilliam/linux-vfio: (32 commits)
vfio: Fix NULL pointer dereference caused by uninitialized group->iommufd
docs: vfio: Update vfio.rst per latest interfaces
vfio: Update the kdoc for vfio_device_ops
vfio/mlx5: Fix range size calculation upon tracker creation
vfio: no need to pass kvm pointer during device open
vfio: fix deadlock between group lock and kvm lock
vfio: revert "iommu driver notify callback"
vfio/type1: revert "implement notify callback"
vfio/type1: revert "block on invalid vaddr"
vfio/type1: restore locked_vm
vfio/type1: track locked_vm per dma
vfio/type1: prevent underflow of locked_vm via exec()
vfio/type1: exclude mdevs from VFIO_UPDATE_VADDR
vfio: platform: ignore missing reset if disabled at module init
vfio/mlx5: Improve the target side flow to reduce downtime
vfio/mlx5: Improve the source side flow upon pre_copy
vfio/mlx5: Check whether VF is migratable
samples: fix the prompt about SAMPLE_VFIO_MDEV_MBOCHS
vfio/mdev: Use sysfs_emit() to instead of sprintf()
vfio-mdev: add back CONFIG_VFIO dependency
...
Many of the mdev drivers use a simple counter for keeping track of the
available instances. Move this code to the core code and store the counter
in the mdev_parent. Implement it using correct locking, fixing mdpy.
Drivers just provide the value in the mdev_driver at registration time
and the core code takes care of maintaining it and exposing the value in
sysfs.
[hch: count instances per-parent instead of per-type, use an atomic_t
to avoid taking mdev_list_lock in the show method]
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20220923092652.100656-15-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is only used by one sample to print a fixed string that is pointless.
In general, having a device driver attach sysfs attributes to the parent
is horrific. This should never happen, and always leads to some kind of
liftime bug as it become very difficult for the sysfs attribute to go back
to any data owned by the device driver.
Remove the general mechanism to create this abuse.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-32-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Pull char/misc driver updates from Greg KH:
"Here is the big set of char and misc and other tiny driver subsystem
updates for 5.16-rc1.
Loads of things in here, all of which have been in linux-next for a
while with no reported problems (except for one called out below.)
Included are:
- habanana labs driver updates, including dma_buf usage, reviewed and
acked by the dma_buf maintainers
- iio driver update (going through this tree not staging as they
really do not belong going through that tree anymore)
- counter driver updates
- hwmon driver updates that the counter drivers needed, acked by the
hwmon maintainer
- xillybus driver updates
- binder driver updates
- extcon driver updates
- dma_buf module namespaces added (will cause a build error in arm64
for allmodconfig, but that change is on its way through the drm
tree)
- lkdtm driver updates
- pvpanic driver updates
- phy driver updates
- virt acrn and nitr_enclaves driver updates
- smaller char and misc driver updates"
* tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (386 commits)
comedi: dt9812: fix DMA buffers on stack
comedi: ni_usb6501: fix NULL-deref in command paths
arm64: errata: Enable TRBE workaround for write to out-of-range address
arm64: errata: Enable workaround for TRBE overwrite in FILL mode
coresight: trbe: Work around write to out of range
coresight: trbe: Make sure we have enough space
coresight: trbe: Add a helper to determine the minimum buffer size
coresight: trbe: Workaround TRBE errata overwrite in FILL mode
coresight: trbe: Add infrastructure for Errata handling
coresight: trbe: Allow driver to choose a different alignment
coresight: trbe: Decouple buffer base from the hardware base
coresight: trbe: Add a helper to pad a given buffer area
coresight: trbe: Add a helper to calculate the trace generated
coresight: trbe: Defer the probe on offline CPUs
coresight: trbe: Fix incorrect access of the sink specific data
coresight: etm4x: Add ETM PID for Kryo-5XX
coresight: trbe: Prohibit trace before disabling TRBE
coresight: trbe: End the AUX handle on truncation
coresight: trbe: Do not truncate buffer on IRQ
coresight: trbe: Fix handling of spurious interrupts
...
Reuse the logic in vfio_noiommu_group_alloc to allocate a fake
single-device iommu group for mediated devices by factoring out a common
function, and replacing the noiommu boolean field in struct vfio_group
with an enum to distinguish the three different kinds of groups.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-8-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Originally "type" could be NULL and these checks were required, but we
recently changed how "type" is assigned and that's no longer the case.
Now "type" points to an element in the middle of a non-NULL array.
Removing the checks does not affect runtime at all, but it makes the
code a little bit simpler to read.
Fixes: 3d3a360e57 ("vfio/mbochs: Use mdev_get_type_group_id()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <20210429095327.GY1981@kadam>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
