Following patches will change the APIs to use the struct file as the handle
instead of the vfio_group, so hang on to a reference to it with the same
duration of as the vfio_group.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

To make it easier to read and change in following patches.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Now that the iommu core takes care of isolation there is no race between
driver attach and container unset. Once iommu_group_release_dma_owner()
returns the device can immediately be re-used.

Remove this mechanism.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/0-v1-a1e8791d795b+6b-vfio_container_q_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Merge IOMMU dependencies for vfio.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Once the group enters 'owned' mode it can never be assigned back to the
default_domain or to a NULL domain. It must always be actively assigned to
a current domain. If the caller hasn't provided a domain then the core
must provide an explicit DMA blocking domain that has no DMA map.

Lazily create a group-global blocking DMA domain when
iommu_group_claim_dma_owner is first called and immediately assign the
group to it. This ensures that DMA is immediately fully isolated on all
IOMMU drivers.

If the user attaches/detaches while owned then detach will set the group
back to the blocking domain.

Slightly reorganize the call chains so that
__iommu_group_set_core_domain() is the function that removes any caller
configured domain and sets the domains back a core owned domain with an
appropriate lifetime.

__iommu_group_set_domain() is the worker function that can change the
domain assigned to a group to any target domain, including NULL.

Add comments clarifying how the NULL vs detach_dev vs default_domain works
based on Robin's remarks.

This fixes an oops with VFIO and SMMUv3 because VFIO will call
iommu_detach_group() and then immediately iommu_domain_free(), but
SMMUv3 has no way to know that the domain it is holding a pointer to
has been freed. Now the iommu_detach_group() will assign the blocking
domain and SMMUv3 will no longer hold a stale domain reference.

Fixes: 1ea2a07a ("iommu: Add DMA ownership management interfaces")
Reported-by: Qian Cai <quic_qiancai@quicinc.com>
Tested-by: Baolu Lu <baolu.lu@linux.intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Co-developed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
--

Just minor polishing as discussed

v3:
 - Change names to __iommu_group_set_domain() /
   __iommu_group_set_core_domain()
 - Clarify comments
 - Call __iommu_group_set_domain() directly in
   iommu_group_release_dma_owner() since we know it is always selecting
   the default_domain
 - Remove redundant detach_dev ops check in __iommu_detach_device and
   make the added WARN_ON fail instead
 - Check for blocking_domain in __iommu_attach_group() so VFIO can
   actually attach a new group
 - Update comments and spelling
 - Fix missed change to new_domain in iommu_group_do_detach_device()

v2: https://lore.kernel.org/r/0-v2-f62259511ac0+6-iommu_dma_block_jgg@nvidia.com
v1: https://lore.kernel.org/r/0-v1-6e9d2d0a759d+11b-iommu_dma_block_jgg@nvidia.comReviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/0-v3-db7f0785022b+149-iommu_dma_block_jgg@nvidia.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

The last user of this function is in PCI callbacks that want to convert
their struct pci_dev to a vfio_device. Instead of searching use the
vfio_device available trivially through the drvdata.

When a callback in the device_driver is called, the caller must hold the
device_lock() on dev. The purpose of the device_lock is to prevent
remove() from being called (see __device_release_driver), and allow the
driver to safely interact with its drvdata without races.

The PCI core correctly follows this and holds the device_lock() when
calling error_detected (see report_error_detected) and
sriov_configure (see sriov_numvfs_store).

Further, since the drvdata holds a positive refcount on the vfio_device
any access of the drvdata, under the device_lock(), from a driver callback
needs no further protection or refcounting.

Thus the remark in the vfio_device_get_from_dev() comment does not apply
here, VFIO PCI drivers all call vfio_unregister_group_dev() from their
remove callbacks under the device_lock() and cannot race with the
remaining callers.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v4-c841817a0349+8f-vfio_get_from_dev_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Having a consistent pointer in the drvdata will allow the next patch to
make use of the drvdata from some of the core code helpers.

Use a WARN_ON inside vfio_pci_core_register_device() to detect drivers
that miss this.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-c841817a0349+8f-vfio_get_from_dev_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

When the open_device() op is called the container_users is incremented and
held incremented until close_device(). Thus, so long as drivers call
functions within their open_device()/close_device() region they do not
need to worry about the container_users.

These functions can all only be called between open_device() and
close_device():

  vfio_pin_pages()
  vfio_unpin_pages()
  vfio_dma_rw()
  vfio_register_notifier()
  vfio_unregister_notifier()

Eliminate the calls to vfio_group_add_container_user() and add
vfio_assert_device_open() to detect driver mis-use. This causes the
close_device() op to check device->open_count so always leave it elevated
while calling the op.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/7-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Now that callers have been updated to use the vfio_device APIs the driver
facing group interface is no longer used, delete it:

- vfio_group_get_external_user_from_dev()
- vfio_group_pin_pages()
- vfio_group_unpin_pages()
- vfio_group_iommu_domain()

--
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/6-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Use the existing vfio_device versions of vfio_(un)pin_pages(). There is no
reason to use a group interface here, kvmgt has easy access to a
vfio_device.

Delete kvmgt_vdev::vfio_group since these calls were the last users.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Zhi Wang <zhi.a.wang@intel.com>
Link: https://lore.kernel.org/r/5-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. Change vfio_dma_rw() to take in the
struct vfio_device and move the container users that would have been held
by vfio_group_get_external_user_from_dev() to vfio_dma_rw() directly, like
vfio_pin/unpin_pages().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. The struct vfio_device already
contains the group we need so this avoids complexity, extra refcountings,
and a confusing lifecycle model.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

The next patch wants the vfio_device instead. There is no reason to store
a pointer here since we can container_of back to the vfio_device.
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

All callers have a struct vfio_device trivially available, pass it in
directly and avoid calling the expensive vfio_group_get_from_dev().
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

IOMMU groups have been mandatory for some time now, so a device without
one is necessarily a device without any usable IOMMU, therefore the
iommu_present() check is redundant (or at best unhelpful).
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/537103bbd7246574f37f2c88704d7824a3a889f2.1649160714.git.robin.murphy@arm.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

Merge GVT-g dependencies for vfio.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Merge tag 'mlx5-lm-parallel' of https://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux into v5.19/vfio/next

Improve mlx5 live migration driver

From Yishai:

This series improves mlx5 live migration driver in few aspects as of
below.

Refactor to enable running migration commands in parallel over the PF
command interface.

To achieve that we exposed from mlx5_core an API to let the VF be
notified before that the PF command interface goes down/up. (e.g. PF
reload upon health recovery).

Once having the above functionality in place mlx5 vfio doesn't need any
more to obtain the global PF lock upon using the command interface but
can rely on the above mechanism to be in sync with the PF.

This can enable parallel VFs migration over the PF command interface
from kernel driver point of view.

In addition,
Moved to use the PF async command mode for the SAVE state command.
This enables returning earlier to user space upon issuing successfully
the command and improve latency by let things run in parallel.

Alex, as this series touches mlx5_core we may need to send this in a
pull request format to VFIO to avoid conflicts before acceptance.

Link: https://lore.kernel.org/all/20220510090206.90374-1-yishaih@nvidia.comSigned-of-by: Leon Romanovsky <leonro@nvidia.com>

Use the PF asynchronous command mode for the SAVE state command.

This enables returning earlier to user space upon issuing successfully
the command and improve latency by let things run in parallel.

Link: https://lore.kernel.org/r/20220510090206.90374-5-yishaih@nvidia.comSigned-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Refactor to enable different VFs to run their commands over the PF
command interface in parallel and to not block one each other.

This is done by not using the global PF lock that was used before but
relying on the VF attach/detach mechanism to sync.

Link: https://lore.kernel.org/r/20220510090206.90374-4-yishaih@nvidia.comSigned-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Manage the VF attach/detach callback from the PF.

This lets the driver to enable parallel VFs migration as will be
introduced in the next patch.

As part of this, reorganize the VF is migratable code to be in a
separate function and rename it to be set_migratable() to match its
functionality.

Link: https://lore.kernel.org/r/20220510090206.90374-3-yishaih@nvidia.comSigned-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Expose mlx5_sriov_blocking_notifier_register / unregister APIs to let a
VF register to be notified for its enablement / disablement by the PF.

Upon VF probe it will call mlx5_sriov_blocking_notifier_register() with
its notifier block and upon VF remove it will call
mlx5_sriov_blocking_notifier_unregister() to drop its registration.

This can give a VF the ability to clean some resources upon disable
before that the command interface goes down and on the other hand sets
some stuff before that it's enabled.

This may be used by a VF which is migration capable in few cases.(e.g.
PF load/unload upon an health recovery).

Link: https://lore.kernel.org/r/20220510090206.90374-2-yishaih@nvidia.comSigned-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Pull parisc architecture fixes from Helge Deller:
 "Some reverts of existing patches, which were necessary because of boot
  issues due to wrong CPU clock handling and cache issues which led to
  userspace segfaults with 32bit kernels. Dave has a whole bunch of
  upcoming cache fixes which I then plan to push in the next merge
  window.

  Other than that just small updates and fixes, e.g. defconfig updates,
  spelling fixes, a clocksource fix, boot topology fixes and a fix for
  /proc/cpuinfo output to satisfy lscpu"

* tag 'for-5.18/parisc-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  Revert "parisc: Increase parisc_cache_flush_threshold setting"
  parisc: Mark cr16 clock unstable on all SMP machines
  parisc: Fix typos in comments
  parisc: Change MAX_ADDRESS to become unsigned long long
  parisc: Merge model and model name into one line in /proc/cpuinfo
  parisc: Re-enable GENERIC_CPU_DEVICES for !SMP
  parisc: Update 32- and 64-bit defconfigs
  parisc: Only list existing CPUs in cpu_possible_mask
  Revert "parisc: Fix patch code locking and flushing"
  Revert "parisc: Mark sched_clock unstable only if clocks are not syncronized"
  Revert "parisc: Mark cr16 CPU clocksource unstable on all SMP machines"

Pull powerpc fixes from Michael Ellerman:

 - Fix the DWARF CFI in our VDSO time functions, allowing gdb to
   backtrace through them correctly.

 - Fix a buffer overflow in the papr_scm driver, only triggerable by
   hypervisor input.

 - A fix in the recently added QoS handling for VAS (used for
   communicating with coprocessors).

Thanks to Alan Modra, Haren Myneni, Kajol Jain, and Segher Boessenkool.

* tag 'powerpc-5.18-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Fix buffer overflow issue with CONFIG_FORTIFY_SOURCE
  powerpc/vdso: Fix incorrect CFI in gettimeofday.S
  powerpc/pseries/vas: Use QoS credits from the userspace

Pull x86 fix from Thomas Gleixner:
 "A fix and an email address update:

   - Prevent FPU state corruption.

     The condition in irq_fpu_usable() grants FPU usage when the FPU is
     not used in the kernel. That's just wrong as it does not take the
     fpregs_lock()'ed regions into account. If FPU usage happens within
     such a region from interrupt context, then the FPU state gets
     corrupted.

     That's a long standing bug, which got unearthed by the recent
     changes to the random code.

   - Josh wants to use his kernel.org email address"

* tag 'x86-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Prevent FPU state corruption
  MAINTAINERS: Update Josh Poimboeuf's email address

Pull timer fix from Thomas Gleixner:
 "A fix and an email address update:

   - Mark the NMI safe time accessors notrace to prevent tracer
     recursion when they are selected as trace clocks.

   - John Stultz has a new email address"

* tag 'timers-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Mark NMI safe time accessors as notrace
  MAINTAINERS: Update email address for John Stultz

This reverts commit a58e9d09.

Triggers segfaults with 32-bit kernels on PA8500 machines.
Signed-off-by: Helge Deller <deller@gmx.de>

Pull irq fix from Thomas Gleixner:
 "A fix for the threaded interrupt core.

  A quick sequence of request/free_irq() can result in a hang because
  the interrupt thread did not reach the thread function and got stopped
  in the kthread core already. That leaves a state active counter
  arround which makes a invocation of synchronized_irq() on that
  interrupt hang forever.

  Ensure that the thread reached the thread function in request_irq() to
  prevent that"

* tag 'irq-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Synchronize interrupt thread startup

Pull locking fixlet from Thomas Gleixner:
 "Just a email address update for MAINTAINERS and mailmap"

* tag 'locking-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: MAINTAINERS, .mailmap: Update André's email address

The cr16 interval timers are not synchronized across CPUs, even with just
one dual-core CPU. This becomes visible if the machines have a longer
uptime.
Signed-off-by: Helge Deller <deller@gmx.de>

Various spelling mistakes in comments.
Detected with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Helge Deller <deller@gmx.de>

Dave noticed that for the 32-bit kernel MAX_ADDRESS should be a ULL,
otherwise this define would become 0:
	MAX_ADDRESS   (1UL << MAX_ADDRBITS)
It has no real effect on the kernel.
Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>

The Linux tool "lscpu" shows the double amount of CPUs if we have
"model" and "model name" in two different lines in /proc/cpuinfo.
This change combines the model and the model name into one line.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org

In commit 62773112 ("parisc: Switch from GENERIC_CPU_DEVICES to
GENERIC_ARCH_TOPOLOGY") GENERIC_CPU_DEVICES was unconditionally turned
off, but this triggers a warning in topology_add_dev(). Turning it back
on for the !SMP case avoids this warning.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 62773112 ("parisc: Switch from GENERIC_CPU_DEVICES to GENERIC_ARCH_TOPOLOGY")
Signed-off-by: Helge Deller <deller@gmx.de>

Enable CONFIG_CGROUPS=y on 32-bit defconfig for systemd-support, and
enable CONFIG_NAMESPACES and CONFIG_USER_NS.
Signed-off-by: Helge Deller <deller@gmx.de>

The inventory knows which CPUs are in the system, so this bitmask should
be in cpu_possible_mask instead of the bitmask based on CONFIG_NR_CPUS.

Reset the cpu_possible_mask before scanning the system for CPUs, and
mark each existing CPU as possible during initialization of that CPU.

This avoids those warnings later on too:

 register_cpu_capacity_sysctl: too early to get CPU4 device!
Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>

This reverts commit a9fe7fa7.

Leads to segfaults on 32bit kernel.
Signed-off-by: Helge Deller <deller@gmx.de>

This reverts commit d97180ad.

It triggers RCU stalls at boot with a 32-bit kernel.
Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # v5.15+

This reverts commit afdb4a5b.

It triggers RCU stalls at boot with a 32-bit kernel.
Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # v5.16+

Pull PASID fix from Thomas Gleixner:
 "A single bugfix for the PASID management code, which freed the PASID
  too early. The PASID needs to be tied to the mm lifetime, not to the
  address space lifetime"

* tag 'core-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mm: Fix PASID use-after-free issue