8 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
1aaba11da9 driver core: class: remove module * from class_create()
The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something.  So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 15:16:33 +01:00
Linus Torvalds
cac85e4616 VFIO updates for v6.3-rc1
- 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  - Update outdated vfio documentation due to new IOMMUFD interfaces in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)
 -----BEGIN PGP SIGNATURE-----
 
 iQJPBAABCAA5FiEEQvbATlQL0amee4qQI5ubbjuwiyIFAmP5GC0bHGFsZXgud2ls
 bGlhbXNvbkByZWRoYXQuY29tAAoJECObm247sIsiGoMP/Ajgc05dq2HGt0ZdTj3d
 /2fgFa/8GXv9t/Md4neHkvKppeHsyL6R9s/OlGb2zQMrZ9wTurW5s4pW4fLIcpNV
 v1vyQSLYMCtj/FT3kG38fZdJwF9NGnC+B+bY4ak+V2rWaKs2vT6fUG6YpzxuBU3T
 jRD41frtszXIp3i8bIPfaoKt/SydUrx12UJAKSks4eDM4aOlxKhpc3VB1vwaSmHB
 MgZMRPVQOGUubKJWb3u07tYOd8NHpBpD3HVUb8IlB2//tSqSPgq3GaKr/B25YzH+
 192vgGrm19aKYQ4U0KPLSH4QGG01bia4LqArbVAhBMwzgKK1dE24dk2YBVj+yePx
 5XXHWv85gLpkev5aLAxsN75/qCtwhYYYB9vBohp8jhXjQU1GXdj9DAht5+c5I3sk
 SZcczmtuZ10X2XXT7fA5iRsG7o3Uxg1VikxYLT0Zhu/0DLc+wQrvum+mmu3sKscx
 qcJyTQXhNTDFzBRRTw6KdyCShbG9gFITysf9Xw/n2y3bxzlfy3Ttf617auYFv6fQ
 ed3kGiT+S16U/dr2b99qQZyn1eIbzOSkz/oWOXwvCWoBdPTEks9f7pDn9Kk6O641
 8tf7qj3vpkOccg71EbVCF6JV5JrhtXDOJVzWIkfQWkoi7qI4ONZ/EdEGTnWY77RY
 urbhuR4UO1iG0nX+yQIFXhDR
 =QqPa
 -----END PGP SIGNATURE-----

Merge tag 'vfio-v6.3-rc1' of https://github.com/awilliam/linux-vfio

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
  ...
2023-02-25 11:52:57 -08:00
Yan Zhao
d649c34cb9 vfio: Fix NULL pointer dereference caused by uninitialized group->iommufd
group->iommufd is not initialized for the iommufd_ctx_put()

[20018.331541] BUG: kernel NULL pointer dereference, address: 0000000000000000
[20018.377508] RIP: 0010:iommufd_ctx_put+0x5/0x10 [iommufd]
...
[20018.476483] Call Trace:
[20018.479214]  <TASK>
[20018.481555]  vfio_group_fops_unl_ioctl+0x506/0x690 [vfio]
[20018.487586]  __x64_sys_ioctl+0x6a/0xb0
[20018.491773]  ? trace_hardirqs_on+0xc5/0xe0
[20018.496347]  do_syscall_64+0x67/0x90
[20018.500340]  entry_SYSCALL_64_after_hwframe+0x4b/0xb5

Fixes: 9eefba8002c2 ("vfio: Move vfio group specific code into group.c")
Cc: stable@vger.kernel.org
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230222074938.13681-1-yan.y.zhao@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-02-22 10:56:37 -07:00
Matthew Rosato
b0d2d5697e vfio: no need to pass kvm pointer during device open
Nothing uses this value during vfio_device_open anymore so it's safe
to remove it.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230203215027.151988-3-mjrosato@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-02-09 11:41:25 -07:00
Matthew Rosato
2b48f52f2b vfio: fix deadlock between group lock and kvm lock
After 51cdc8bc120e, we have another deadlock scenario between the
kvm->lock and the vfio group_lock with two different codepaths acquiring
the locks in different order.  Specifically in vfio_open_device, vfio
holds the vfio group_lock when issuing device->ops->open_device but some
drivers (like vfio-ap) need to acquire kvm->lock during their open_device
routine;  Meanwhile, kvm_vfio_release will acquire the kvm->lock first
before calling vfio_file_set_kvm which will acquire the vfio group_lock.

To resolve this, let's remove the need for the vfio group_lock from the
kvm_vfio_release codepath.  This is done by introducing a new spinlock to
protect modifications to the vfio group kvm pointer, and acquiring a kvm
ref from within vfio while holding this spinlock, with the reference held
until the last close for the device in question.

Fixes: 51cdc8bc120e ("kvm/vfio: Fix potential deadlock on vfio group_lock")
Reported-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230203215027.151988-2-mjrosato@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-02-09 11:41:25 -07:00
Jason Gunthorpe
c9a397cee9 vfio: Support VFIO_NOIOMMU with iommufd
Add a small amount of emulation to vfio_compat to accept the SET_IOMMU to
VFIO_NOIOMMU_IOMMU and have vfio just ignore iommufd if it is working on a
no-iommu enabled device.

Move the enable_unsafe_noiommu_mode module out of container.c into
vfio_main.c so that it is always available even if VFIO_CONTAINER=n.

This passes Alex's mini-test:

https://github.com/awilliam/tests/blob/master/vfio-noiommu-pci-device-open.c

Link: https://lore.kernel.org/r/0-v3-480cd64a16f7+1ad0-iommufd_noiommu_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-02-03 15:45:23 -04:00
Linus Torvalds
71a7507afb Driver Core changes for 6.2-rc1
Here is the set of driver core and kernfs changes for 6.2-rc1.
 
 The "big" change in here is the addition of a new macro,
 container_of_const() that will preserve the "const-ness" of a pointer
 passed into it.
 
 The "problem" of the current container_of() macro is that if you pass in
 a "const *", out of it can comes a non-const pointer unless you
 specifically ask for it.  For many usages, we want to preserve the
 "const" attribute by using the same call.  For a specific example, this
 series changes the kobj_to_dev() macro to use it, allowing it to be used
 no matter what the const value is.  This prevents every subsystem from
 having to declare 2 different individual macros (i.e.
 kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
 the const value at build time, which having 2 macros would not do
 either.
 
 The driver for all of this have been discussions with the Rust kernel
 developers as to how to properly mark driver core, and kobject, objects
 as being "non-mutable".  The changes to the kobject and driver core in
 this pull request are the result of that, as there are lots of paths
 where kobjects and device pointers are not modified at all, so marking
 them as "const" allows the compiler to enforce this.
 
 So, a nice side affect of the Rust development effort has been already
 to clean up the driver core code to be more obvious about object rules.
 
 All of this has been bike-shedded in quite a lot of detail on lkml with
 different names and implementations resulting in the tiny version we
 have in here, much better than my original proposal.  Lots of subsystem
 maintainers have acked the changes as well.
 
 Other than this change, included in here are smaller stuff like:
   - kernfs fixes and updates to handle lock contention better
   - vmlinux.lds.h fixes and updates
   - sysfs and debugfs documentation updates
   - device property updates
 
 All of these have been in the linux-next tree for quite a while with no
 problems, OTHER than some merge issues with other trees that should be
 obvious when you hit them (block tree deletes a driver that this tree
 modifies, iommufd tree modifies code that this tree also touches).  If
 there are merge problems with these trees, please let me know.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCY5wz3A8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yks0ACeKYUlVgCsER8eYW+x18szFa2QTXgAn2h/VhZe
 1Fp53boFaQkGBjl8mGF8
 =v+FB
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core and kernfs changes for 6.2-rc1.

  The "big" change in here is the addition of a new macro,
  container_of_const() that will preserve the "const-ness" of a pointer
  passed into it.

  The "problem" of the current container_of() macro is that if you pass
  in a "const *", out of it can comes a non-const pointer unless you
  specifically ask for it. For many usages, we want to preserve the
  "const" attribute by using the same call. For a specific example, this
  series changes the kobj_to_dev() macro to use it, allowing it to be
  used no matter what the const value is. This prevents every subsystem
  from having to declare 2 different individual macros (i.e.
  kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
  the const value at build time, which having 2 macros would not do
  either.

  The driver for all of this have been discussions with the Rust kernel
  developers as to how to properly mark driver core, and kobject,
  objects as being "non-mutable". The changes to the kobject and driver
  core in this pull request are the result of that, as there are lots of
  paths where kobjects and device pointers are not modified at all, so
  marking them as "const" allows the compiler to enforce this.

  So, a nice side affect of the Rust development effort has been already
  to clean up the driver core code to be more obvious about object
  rules.

  All of this has been bike-shedded in quite a lot of detail on lkml
  with different names and implementations resulting in the tiny version
  we have in here, much better than my original proposal. Lots of
  subsystem maintainers have acked the changes as well.

  Other than this change, included in here are smaller stuff like:

   - kernfs fixes and updates to handle lock contention better

   - vmlinux.lds.h fixes and updates

   - sysfs and debugfs documentation updates

   - device property updates

  All of these have been in the linux-next tree for quite a while with
  no problems"

* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
  device property: Fix documentation for fwnode_get_next_parent()
  firmware_loader: fix up to_fw_sysfs() to preserve const
  usb.h: take advantage of container_of_const()
  device.h: move kobj_to_dev() to use container_of_const()
  container_of: add container_of_const() that preserves const-ness of the pointer
  driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
  driver core: fix up missed scsi/cxlflash class.devnode() conversion.
  driver core: fix up some missing class.devnode() conversions.
  driver core: make struct class.devnode() take a const *
  driver core: make struct class.dev_uevent() take a const *
  cacheinfo: Remove of_node_put() for fw_token
  device property: Add a blank line in Kconfig of tests
  device property: Rename goto label to be more precise
  device property: Move PROPERTY_ENTRY_BOOL() a bit down
  device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
  kernfs: fix all kernel-doc warnings and multiple typos
  driver core: pass a const * into of_device_uevent()
  kobject: kset_uevent_ops: make name() callback take a const *
  kobject: kset_uevent_ops: make filter() callback take a const *
  kobject: make kobject_namespace take a const *
  ...
2022-12-16 03:54:54 -08:00
Yi Liu
9eefba8002 vfio: Move vfio group specific code into group.c
This prepares for compiling out vfio group after vfio device cdev is
added. No vfio_group decode code should be in vfio_main.c, and neither
device->group reference should be in vfio_main.c.

No functional change is intended.

Link: https://lore.kernel.org/r/20221201145535.589687-11-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Yu He <yu.he@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-12-05 08:56:01 -04:00