Commit Graph
1138 Commits
Author SHA1 Message Date
Artem SadovnikovandGreg Kroah-Hartman 2e07a9fe51 vfio/mlx5: fix possible overflow in tracking max message size
[ Upstream commit b306019848 ]

MLX cap pg_track_log_max_msg_size consists of 5 bits, value of which is
used as power of 2 for max_msg_size. This can lead to multiplication
overflow between max_msg_size (u32) and integer constant, and afterwards
incorrect value is being written to rq_size.

Fix this issue by extending integer constant to u64 type.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Artem Sadovnikov <a.sadovnikov@ispras.ru>
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20250701144017.2410-2-a.sadovnikov@ispras.ru
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28 16:28:29 +02:00
Keith BuschandGreg Kroah-Hartman 106ab3cd02 vfio/type1: conditional rescheduling while pinning
[ Upstream commit b1779e4f20 ]

A large DMA mapping request can loop through dma address pinning for
many pages. In cases where THP can not be used, the repeated vmf_insert_pfn can
be costly, so let the task reschedule as need to prevent CPU stalls. Failure to
do so has potential harmful side effects, like increased memory pressure
as unrelated rcu tasks are unable to make their reclaim callbacks and
result in OOM conditions.

 rcu: INFO: rcu_sched self-detected stall on CPU
 rcu:   36-....: (20999 ticks this GP) idle=b01c/1/0x4000000000000000 softirq=35839/35839 fqs=3538
 rcu:            hardirqs   softirqs   csw/system
 rcu:    number:        0        107            0
 rcu:   cputime:       50          0        10446   ==> 10556(ms)
 rcu:   (t=21075 jiffies g=377761 q=204059 ncpus=384)
...
  <TASK>
  ? asm_sysvec_apic_timer_interrupt+0x16/0x20
  ? walk_system_ram_range+0x63/0x120
  ? walk_system_ram_range+0x46/0x120
  ? pgprot_writethrough+0x20/0x20
  lookup_memtype+0x67/0xf0
  track_pfn_insert+0x20/0x40
  vmf_insert_pfn_prot+0x88/0x140
  vfio_pci_mmap_huge_fault+0xf9/0x1b0 [vfio_pci_core]
  __do_fault+0x28/0x1b0
  handle_mm_fault+0xef1/0x2560
  fixup_user_fault+0xf5/0x270
  vaddr_get_pfns+0x169/0x2f0 [vfio_iommu_type1]
  vfio_pin_pages_remote+0x162/0x8e0 [vfio_iommu_type1]
  vfio_iommu_type1_ioctl+0x1121/0x1810 [vfio_iommu_type1]
  ? futex_wake+0x1c1/0x260
  x64_sys_call+0x234/0x17a0
  do_syscall_64+0x63/0x130
  ? exc_page_fault+0x63/0x130
  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20250715184622.3561598-1-kbusch@meta.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28 16:28:29 +02:00
Alex WilliamsonandGreg Kroah-Hartman 349436bf11 vfio/pci: Separate SR-IOV VF dev_set
[ Upstream commit e908f58b6b ]

In the below noted Fixes commit we introduced a reflck mutex to allow
better scaling between devices for open and close.  The reflck was
based on the hot reset granularity, device level for root bus devices
which cannot support hot reset or bus/slot reset otherwise.  Overlooked
in this were SR-IOV VFs, where there's also no bus reset option, but
the default for a non-root-bus, non-slot-based device is bus level
reflck granularity.

The reflck mutex has since become the dev_set mutex (via commit
2cd8b14aaa ("vfio/pci: Move to the device set infrastructure")) and
is our defacto serialization for various operations and ioctls.  It
still seems to be the case though that sets of vfio-pci devices really
only need serialization relative to hot resets affecting the entire
set, which is not relevant to SR-IOV VFs.  As described in the Closes
link below, this serialization contributes to startup latency when
multiple VFs sharing the same "bus" are opened concurrently.

Mark the device itself as the basis of the dev_set for SR-IOV VFs.

Reported-by: Aaron Lewis <aaronlewis@google.com>
Closes: https://lore.kernel.org/all/20250626180424.632628-1-aaronlewis@google.com
Tested-by: Aaron Lewis <aaronlewis@google.com>
Fixes: e309df5b0c ("vfio/pci: Parallelize device open and release")
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20250626225623.1180952-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:59 +02:00
Brett CreeleyandGreg Kroah-Hartman 7dbfae90c5 vfio/pds: Fix missing detach_ioas op
[ Upstream commit fe24d5bc63 ]

When CONFIG_IOMMUFD is enabled and a device is bound to the pds_vfio_pci
driver, the following WARN_ON() trace is seen and probe fails:

WARNING: CPU: 0 PID: 5040 at drivers/vfio/vfio_main.c:317 __vfio_register_dev+0x130/0x140 [vfio]
<...>
pds_vfio_pci 0000:08:00.1: probe with driver pds_vfio_pci failed with error -22

This is because the driver's vfio_device_ops.detach_ioas isn't set.

Fix this by using the generic vfio_iommufd_physical_detach_ioas
function.

Fixes: 38fe3975b4 ("vfio/pds: Initial support for pds VFIO driver")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20250702163744.69767-1-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:59 +02:00
Jacob PanandGreg Kroah-Hartman 9546b26d39 vfio: Prevent open_count decrement to negative
[ Upstream commit 982ddd59ed ]

When vfio_df_close() is called with open_count=0, it triggers a warning in
vfio_assert_device_open() but still decrements open_count to -1. This allows
a subsequent open to incorrectly pass the open_count == 0 check, leading to
unintended behavior, such as setting df->access_granted = true.

For example, running an IOMMUFD compat no-IOMMU device with VFIO tests
(https://github.com/awilliam/tests/blob/master/vfio-noiommu-pci-device-open.c)
results in a warning and a failed VFIO_GROUP_GET_DEVICE_FD ioctl on the first
run, but the second run succeeds incorrectly.

Add checks to avoid decrementing open_count below zero.

Fixes: 05f37e1c03 ("vfio: Pass struct vfio_device_file * to vfio_device_open/close()")
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250618234618.1910456-2-jacob.pan@linux.microsoft.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:59 +02:00
Jacob PanandGreg Kroah-Hartman a6c5e25861 vfio: Fix unbalanced vfio_df_close call in no-iommu mode
[ Upstream commit b25e271b37 ]

For devices with no-iommu enabled in IOMMUFD VFIO compat mode, the group open
path skips vfio_df_open(), leaving open_count at 0. This causes a warning in
vfio_assert_device_open(device) when vfio_df_close() is called during group
close.

The correct behavior is to skip only the IOMMUFD bind in the device open path
for no-iommu devices. Commit 6086efe734 omitted vfio_df_open(), which was
too broad. This patch restores the previous behavior, ensuring
the vfio_df_open is called in the group open path.

Fixes: 6086efe734 ("vfio-iommufd: Move noiommu compat validation out of vfio_iommufd_bind()")
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20250618234618.1910456-1-jacob.pan@linux.microsoft.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-15 12:08:59 +02:00
Li RongQingandGreg Kroah-Hartman 801677040b vfio/type1: Fix error unwind in migration dirty bitmap allocation
[ Upstream commit 4518e5a60c ]

When setting up dirty page tracking at the vfio IOMMU backend for
device migration, if an error is encountered allocating a tracking
bitmap, the unwind loop fails to free previously allocated tracking
bitmaps.  This occurs because the wrong loop index is used to
generate the tracking object.  This results in unintended memory
usage for the life of the current DMA mappings where bitmaps were
successfully allocated.

Use the correct loop index to derive the tracking object for
freeing during unwind.

Fixes: d6a4c18566 ("vfio iommu: Implementation of ioctl for dirty pages tracking")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Link: https://lore.kernel.org/r/20250521034647.2877-1-lirongqing@baidu.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:17 +02:00
Longfang LiuandGreg Kroah-Hartman b5ef128926 hisi_acc_vfio_pci: bugfix live migration function without VF device driver
[ Upstream commit 2777a40998 ]

If the VF device driver is not loaded in the Guest OS and we attempt to
perform device data migration, the address of the migrated data will
be NULL.
The live migration recovery operation on the destination side will
access a null address value, which will cause access errors.

Therefore, live migration of VMs without added VF device drivers
does not require device data migration.
In addition, when the queue address data obtained by the destination
is empty, device queue recovery processing will not be performed.

Fixes: b0eed08590 ("hisi_acc_vfio_pci: Add support for VFIO live migration")
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20250510081155.55840-6-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:16 +02:00
Longfang LiuandGreg Kroah-Hartman 5be5cd86d1 hisi_acc_vfio_pci: add eq and aeq interruption restore
[ Upstream commit 3495cec078 ]

In order to ensure that the task packets of the accelerator
device are not lost during the migration process, it is necessary
to send an EQ and AEQ command to the device after the live migration
is completed and to update the completion position of the task queue.

Let the device recheck the completed tasks data and if there are
uncollected packets, device resend a task completion interrupt
to the software.

Fixes: b0eed08590 ("hisi_acc_vfio_pci: Add support for VFIO live migration")
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20250510081155.55840-3-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:16 +02:00
Longfang LiuandGreg Kroah-Hartman f0423873e7 hisi_acc_vfio_pci: fix XQE dma address error
[ Upstream commit 8bb7170c5a ]

The dma addresses of EQE and AEQE are wrong after migration and
results in guest kernel-mode encryption services  failure.
Comparing the definition of hardware registers, we found that
there was an error when the data read from the register was
combined into an address. Therefore, the address combination
sequence needs to be corrected.

Even after fixing the above problem, we still have an issue
where the Guest from an old kernel can get migrated to
new kernel and may result in wrong data.

In order to ensure that the address is correct after migration,
if an old magic number is detected, the dma address needs to be
updated.

Fixes: b0eed08590 ("hisi_acc_vfio_pci: Add support for VFIO live migration")
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20250510081155.55840-2-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:16 +02:00
Alex WilliamsonandGreg Kroah-Hartman 743bb75325 vfio/pci: Handle INTx IRQ_NOTCONNECTED
[ Upstream commit 860be250fc ]

Some systems report INTx as not routed by setting pdev->irq to
IRQ_NOTCONNECTED, resulting in a -ENOTCONN error when trying to
setup eventfd signaling.  Include this in the set of conditions
for which the PIN register is virtualized to zero.

Additionally consolidate vfio_pci_get_irq_count() to use this
virtualized value in reporting INTx support via ioctl and sanity
checking ioctl paths since pdev->irq is re-used when the device
is in MSI mode.

The combination of these results in both the config space of the
device and the ioctl interface behaving as if the device does not
support INTx.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20250311230623.1264283-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04 14:41:58 +02:00
Greg Kroah-Hartman 50a0821c82 Revert "vfio/platform: check the bounds of read/write syscalls"
This reverts commit 03844b1908.

It had been committed multiple times to the tree, and isn't needed
again.

Link: https://lore.kernel.org/r/a082db2605514513a0a8568382d5bd2b6f1877a0.camel@cyberus-technology.de
Reported-by: Stefan Nürnberger <stefan.nuernberger@cyberus-technology.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-21 13:57:27 +01:00
Ramesh ThomasandGreg Kroah-Hartman 2a0696363d vfio/pci: Enable iowrite64 and ioread64 for vfio pci
[ Upstream commit 2b938e3db3 ]

Definitions of ioread64 and iowrite64 macros in asm/io.h called by vfio
pci implementations are enclosed inside check for CONFIG_GENERIC_IOMAP.
They don't get defined if CONFIG_GENERIC_IOMAP is defined. Include
linux/io-64-nonatomic-lo-hi.h to define iowrite64 and ioread64 macros
when they are not defined. io-64-nonatomic-lo-hi.h maps the macros to
generic implementation in lib/iomap.c. The generic implementation does
64 bit rw if readq/writeq is defined for the architecture, otherwise it
would do 32 bit back to back rw.

Note that there are two versions of the generic implementation that
differs in the order the 32 bit words are written if 64 bit support is
not present. This is not the little/big endian ordering, which is
handled separately. This patch uses the lo followed by hi word ordering
which is consistent with current back to back implementation in the
vfio/pci code.

Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20241210131938.303500-2-ramesh.thomas@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 13:57:11 +01:00
Alex WilliamsonandGreg Kroah-Hartman 03844b1908 vfio/platform: check the bounds of read/write syscalls
commit ce9ff21ea8 upstream.

count and offset are passed from user space and not checked, only
offset is capped to 40 bits, which can be used to read/write out of
bounds of the device.

Fixes: 6e3f264560 (“vfio/platform: read and write support for the device fd”)
Cc: stable@vger.kernel.org
Reported-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Mostafa Saleh <smostafa@google.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17 09:40:37 +01:00
Qasim IjazandGreg Kroah-Hartman 38ac76fc06 iommufd/iova_bitmap: Fix shift-out-of-bounds in iova_bitmap_offset_to_index()
[ Upstream commit e24c155105 ]

Resolve a UBSAN shift-out-of-bounds issue in iova_bitmap_offset_to_index()
where shifting the constant "1" (of type int) by bitmap->mapped.pgshift
(an unsigned long value) could result in undefined behavior.

The constant "1" defaults to a 32-bit "int", and when "pgshift" exceeds
31 (e.g., pgshift = 63) the shift operation overflows, as the result
cannot be represented in a 32-bit type.

To resolve this, the constant is updated to "1UL", promoting it to an
unsigned long type to match the operand's type.

Fixes: 58ccf0190d ("vfio: Add an IOVA bitmap support")
Link: https://patch.msgid.link/r/20250113223820.10713-1-qasdev00@gmail.com
Reported-by: syzbot <syzbot+85992ace37d5b7b51635@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=85992ace37d5b7b51635
Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:52:22 +01:00
Alex WilliamsonandGreg Kroah-Hartman c981c32c38 vfio/platform: check the bounds of read/write syscalls
commit ce9ff21ea8 upstream.

count and offset are passed from user space and not checked, only
offset is capped to 40 bits, which can be used to read/write out of
bounds of the device.

Fixes: 6e3f264560 (“vfio/platform: read and write support for the device fd”)
Cc: stable@vger.kernel.org
Reported-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Mostafa Saleh <smostafa@google.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-01 18:37:55 +01:00
Yishai HadasandGreg Kroah-Hartman 032b4122a9 vfio/mlx5: Align the page tracking max message size with the device capability
[ Upstream commit 9c7c5430bc ]

Align the page tracking maximum message size with the device's
capability instead of relying on PAGE_SIZE.

This adjustment resolves a mismatch on systems where PAGE_SIZE is 64K,
but the firmware only supports a maximum message size of 4K.

Now that we rely on the device's capability for max_message_size, we
must account for potential future increases in its value.

Key considerations include:
- Supporting message sizes that exceed a single system page (e.g., an 8K
  message on a 4K system).
- Ensuring the RQ size is adjusted to accommodate at least 4
  WQEs/messages, in line with the device specification.

The above has been addressed as part of the patch.

Fixes: 79c3cf2799 ("vfio/mlx5: Init QP based resources for dirty tracking")
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Yingshun Cui <yicui@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241205122654.235619-1-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 20:00:20 +01:00
Avihai HoronandGreg Kroah-Hartman 06f2fcf498 vfio/pci: Properly hide first-in-list PCIe extended capability
[ Upstream commit fe4bf8d0b6 ]

There are cases where a PCIe extended capability should be hidden from
the user. For example, an unknown capability (i.e., capability with ID
greater than PCI_EXT_CAP_ID_MAX) or a capability that is intentionally
chosen to be hidden from the user.

Hiding a capability is done by virtualizing and modifying the 'Next
Capability Offset' field of the previous capability so it points to the
capability after the one that should be hidden.

The special case where the first capability in the list should be hidden
is handled differently because there is no previous capability that can
be modified. In this case, the capability ID and version are zeroed
while leaving the next pointer intact. This hides the capability and
leaves an anchor for the rest of the capability list.

However, today, hiding the first capability in the list is not done
properly if the capability is unknown, as struct
vfio_pci_core_device->pci_config_map is set to the capability ID during
initialization but the capability ID is not properly checked later when
used in vfio_config_do_rw(). This leads to the following warning [1] and
to an out-of-bounds access to ecap_perms array.

Fix it by checking cap_id in vfio_config_do_rw(), and if it is greater
than PCI_EXT_CAP_ID_MAX, use an alternative struct perm_bits for direct
read only access instead of the ecap_perms array.

Note that this is safe since the above is the only case where cap_id can
exceed PCI_EXT_CAP_ID_MAX (except for the special capabilities, which
are already checked before).

[1]

WARNING: CPU: 118 PID: 5329 at drivers/vfio/pci/vfio_pci_config.c:1900 vfio_pci_config_rw+0x395/0x430 [vfio_pci_core]
CPU: 118 UID: 0 PID: 5329 Comm: simx-qemu-syste Not tainted 6.12.0+ #1
(snip)
Call Trace:
 <TASK>
 ? show_regs+0x69/0x80
 ? __warn+0x8d/0x140
 ? vfio_pci_config_rw+0x395/0x430 [vfio_pci_core]
 ? report_bug+0x18f/0x1a0
 ? handle_bug+0x63/0xa0
 ? exc_invalid_op+0x19/0x70
 ? asm_exc_invalid_op+0x1b/0x20
 ? vfio_pci_config_rw+0x395/0x430 [vfio_pci_core]
 ? vfio_pci_config_rw+0x244/0x430 [vfio_pci_core]
 vfio_pci_rw+0x101/0x1b0 [vfio_pci_core]
 vfio_pci_core_read+0x1d/0x30 [vfio_pci_core]
 vfio_device_fops_read+0x27/0x40 [vfio]
 vfs_read+0xbd/0x340
 ? vfio_device_fops_unl_ioctl+0xbb/0x740 [vfio]
 ? __rseq_handle_notify_resume+0xa4/0x4b0
 __x64_sys_pread64+0x96/0xc0
 x64_sys_call+0x1c3d/0x20d0
 do_syscall_64+0x4d/0x120
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: 89e1f7d4c6 ("vfio: Add PCI device driver")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20241124142739.21698-1-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-09 10:32:31 +01:00
Shivaprasad G BhatandGreg Kroah-Hartman 4ef01846c6 vfio/spapr: Always clear TCEs before unsetting the window
[ Upstream commit 4ba2fdff2e ]

The PAPR expects the TCE table to have no entries at the time of
unset window(i.e. remove-pe). The TCE clear right now is done
before freeing the iommu table. On pSeries, the unset window
makes those entries inaccessible to the OS and the H_PUT/GET calls
fail on them with H_CONSTRAINED.

On PowerNV, this has no side effect as the TCE clear can be done
before the DMA window removal as well.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923273535.1397.1236742071894414895.stgit@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-09-12 11:11:31 +02:00
Yi LiuandGreg Kroah-Hartman f476dffc52 vfio/pci: Init the count variable in collecting hot-reset devices
[ Upstream commit 5a88a3f67e ]

The count variable is used without initialization, it results in mistakes
in the device counting and crashes the userspace if the get hot reset info
path is triggered.

Fixes: f6944d4a0b ("vfio/pci: Collect hot-reset devices to local buffer")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219010
Reported-by: Žilvinas Žaltiena <zaltys@natrix.lt>
Cc: Beld Zhang <beldzhang@gmail.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240710004150.319105-1-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18 13:21:10 +02:00
Alex WilliamsonandGreg Kroah-Hartman 618fbf4c91 vfio/pci: Collect hot-reset devices to local buffer
[ Upstream commit f6944d4a0b ]

Lockdep reports the below circular locking dependency issue.  The
mmap_lock acquisition while holding pci_bus_sem is due to the use of
copy_to_user() from within a pci_walk_bus() callback.

Building the devices array directly into the user buffer is only for
convenience.  Instead we can allocate a local buffer for the array,
bounded by the number of devices on the bus/slot, fill the device
information into this local buffer, then copy it into the user buffer
outside the bus walk callback.

======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc5+ #39 Not tainted
------------------------------------------------------
CPU 0/KVM/4113 is trying to acquire lock:
ffff99a609ee18a8 (&vdev->vma_lock){+.+.}-{4:4}, at: vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]

but task is already holding lock:
ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&mm->mmap_lock){++++}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       __might_fault+0x5c/0x80
       _copy_to_user+0x1e/0x60
       vfio_pci_fill_devs+0x9f/0x130 [vfio_pci_core]
       vfio_pci_walk_wrapper+0x45/0x60 [vfio_pci_core]
       __pci_walk_bus+0x6b/0xb0
       vfio_pci_ioctl_get_pci_hot_reset_info+0x10b/0x1d0 [vfio_pci_core]
       vfio_pci_core_ioctl+0x1cb/0x400 [vfio_pci_core]
       vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #2 (pci_bus_sem){++++}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       down_read+0x3e/0x160
       pci_bridge_wait_for_secondary_bus.part.0+0x33/0x2d0
       pci_reset_bus+0xdd/0x160
       vfio_pci_dev_set_hot_reset+0x256/0x270 [vfio_pci_core]
       vfio_pci_ioctl_pci_hot_reset_groups+0x1a3/0x280 [vfio_pci_core]
       vfio_pci_core_ioctl+0x3b5/0x400 [vfio_pci_core]
       vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #1 (&vdev->memory_lock){+.+.}-{4:4}:
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       down_write+0x3b/0xc0
       vfio_pci_zap_and_down_write_memory_lock+0x1c/0x30 [vfio_pci_core]
       vfio_basic_config_write+0x281/0x340 [vfio_pci_core]
       vfio_config_do_rw+0x1fa/0x300 [vfio_pci_core]
       vfio_pci_config_rw+0x75/0xe50 [vfio_pci_core]
       vfio_pci_rw+0xea/0x1a0 [vfio_pci_core]
       vfs_write+0xea/0x520
       __x64_sys_pwrite64+0x90/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #0 (&vdev->vma_lock){+.+.}-{4:4}:
       check_prev_add+0xeb/0xcc0
       validate_chain+0x465/0x530
       __lock_acquire+0x4e4/0xb90
       lock_acquire+0xbc/0x2d0
       __mutex_lock+0x97/0xde0
       vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
       __do_fault+0x31/0x160
       do_pte_missing+0x65/0x3b0
       __handle_mm_fault+0x303/0x720
       handle_mm_fault+0x10f/0x460
       fixup_user_fault+0x7f/0x1f0
       follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1]
       vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1]
       vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1]
       vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1]
       vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1]
       vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1]
       __x64_sys_ioctl+0x8a/0xc0
       do_syscall_64+0x8d/0x170
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

other info that might help us debug this:

Chain exists of:
  &vdev->vma_lock --> pci_bus_sem --> &mm->mmap_lock

 Possible unsafe locking scenario:

block dm-0: the capability attribute has been deprecated.
       CPU0                    CPU1
       ----                    ----
  rlock(&mm->mmap_lock);
                               lock(pci_bus_sem);
                               lock(&mm->mmap_lock);
  lock(&vdev->vma_lock);

 *** DEADLOCK ***

2 locks held by CPU 0/KVM/4113:
 #0: ffff99a25f294888 (&iommu->lock#2){+.+.}-{4:4}, at: vfio_dma_do_map+0x60/0x440 [vfio_iommu_type1]
 #1: ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1]

stack backtrace:
CPU: 1 PID: 4113 Comm: CPU 0/KVM Not tainted 6.9.0-rc5+ #39
Hardware name: Dell Inc. PowerEdge T640/04WYPY, BIOS 2.15.1 06/16/2022
Call Trace:
 <TASK>
 dump_stack_lvl+0x64/0xa0
 check_noncircular+0x131/0x150
 check_prev_add+0xeb/0xcc0
 ? add_chain_cache+0x10a/0x2f0
 ? __lock_acquire+0x4e4/0xb90
 validate_chain+0x465/0x530
 __lock_acquire+0x4e4/0xb90
 lock_acquire+0xbc/0x2d0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? lock_is_held_type+0x9a/0x110
 __mutex_lock+0x97/0xde0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? lock_acquire+0xbc/0x2d0
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 ? find_held_lock+0x2b/0x80
 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core]
 __do_fault+0x31/0x160
 do_pte_missing+0x65/0x3b0
 __handle_mm_fault+0x303/0x720
 handle_mm_fault+0x10f/0x460
 fixup_user_fault+0x7f/0x1f0
 follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1]
 vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1]
 vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1]
 vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1]
 vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1]
 vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1]
 __x64_sys_ioctl+0x8a/0xc0
 do_syscall_64+0x8d/0x170
 ? rcu_core+0x8d/0x250
 ? __lock_release+0x5e/0x160
 ? rcu_core+0x8d/0x250
 ? lock_release+0x5f/0x120
 ? sched_clock+0xc/0x30
 ? sched_clock_cpu+0xb/0x190
 ? irqtime_account_irq+0x40/0xc0
 ? __local_bh_enable+0x54/0x60
 ? __do_softirq+0x315/0x3ca
 ? lockdep_hardirqs_on_prepare.part.0+0x97/0x140
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8300d0357b
Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 68 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007f82ef3fb948 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8300d0357b
RDX: 00007f82ef3fb990 RSI: 0000000000003b71 RDI: 0000000000000023
RBP: 00007f82ef3fb9c0 R08: 0000000000000000 R09: 0000561b7e0bcac2
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000200000000 R14: 0000381800000000 R15: 0000000000000000
 </TASK>

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240503143138.3562116-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:05 +02:00
Ye BinandGreg Kroah-Hartman 0bd22a4966 vfio/pci: fix potential memory leak in vfio_intx_enable()
[ Upstream commit 82b951e6fb ]

If vfio_irq_ctx_alloc() failed will lead to 'name' memory leak.

Fixes: 18c198c96a ("vfio/pci: Create persistent INTx handler")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/r/20240415015029.3699844-1-yebin10@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:22 +02:00
Arjan van de VenandGreg Kroah-Hartman c516453577 VFIO: Add the SPR_DSA and SPR_IAX devices to the denylist
commit 95feb3160e upstream.

Due to an erratum with the SPR_DSA and SPR_IAX devices, it is not secure to assign
these devices to virtual machines. Add the PCI IDs of these devices to the VFIO
denylist to ensure that this is handled appropriately by the VFIO subsystem.

The SPR_DSA and SPR_IAX devices are on-SOC devices for the Sapphire Rapids
(and related) family of products that perform data movement and compression.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:02:38 +02:00
Brett CreeleyandGreg Kroah-Hartman 66aa5d95ea vfio/pds: Make sure migration file isn't accessed after reset
[ Upstream commit 457f730825 ]

It's possible the migration file is accessed after reset when it has
been cleaned up, especially when it's initiated by the device. This is
because the driver doesn't rip out the filep when cleaning up it only
frees the related page structures and sets its local struct
pds_vfio_lm_file pointer to NULL. This can cause a NULL pointer
dereference, which is shown in the example below during a restore after
a device initiated reset:

BUG: kernel NULL pointer dereference, address: 000000000000000c
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:pds_vfio_get_file_page+0x5d/0xf0 [pds_vfio_pci]
[...]
Call Trace:
 <TASK>
 pds_vfio_restore_write+0xf6/0x160 [pds_vfio_pci]
 vfs_write+0xc9/0x3f0
 ? __fget_light+0xc9/0x110
 ksys_write+0xb5/0xf0
 __x64_sys_write+0x1a/0x20
 do_syscall_64+0x38/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]

Add a disabled flag to the driver's struct pds_vfio_lm_file that gets
set during cleanup. Then make sure to check the flag when the migration
file is accessed via its file_operations. By default this flag will be
false as the memory for struct pds_vfio_lm_file is kzalloc'd, which means
the struct pds_vfio_lm_file is enabled and accessible. Also, since the
file_operations and driver's migration file cleanup happen under the
protection of the same pds_vfio_lm_file.lock, using this flag is thread
safe.

Fixes: 8512ed2563 ("vfio/pds: Always clear the save/restore FDs on reset")
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Link: https://lore.kernel.org/r/20240308182149.22036-2-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:28:59 +02:00
Alex WilliamsonandGreg Kroah-Hartman ee0bd4ad78 vfio/fsl-mc: Block calling interrupt handler without trigger
commit 7447d911af upstream.

The eventfd_ctx trigger pointer of the vfio_fsl_mc_irq object is
initially NULL and may become NULL if the user sets the trigger
eventfd to -1.  The interrupt handler itself is guaranteed that
trigger is always valid between request_irq() and free_irq(), but
the loopback testing mechanisms to invoke the handler function
need to test the trigger.  The triggering and setting ioctl paths
both make use of igate and are therefore mutually exclusive.

The vfio-fsl-mc driver does not make use of irqfds, nor does it
support any sort of masking operations, therefore unlike vfio-pci
and vfio-platform, the flow can remain essentially unchanged.

Cc: Diana Craciun <diana.craciun@oss.nxp.com>
Cc:  <stable@vger.kernel.org>
Fixes: cc0ee20bd9 ("vfio/fsl-mc: trigger an interrupt via eventfd")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-8-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:28:49 +02:00
Alex WilliamsonandGreg Kroah-Hartman 62d4e43a56 vfio/platform: Create persistent IRQ handlers
commit 675daf435e upstream.

The vfio-platform SET_IRQS ioctl currently allows loopback triggering of
an interrupt before a signaling eventfd has been configured by the user,
which thereby allows a NULL pointer dereference.

Rather than register the IRQ relative to a valid trigger, register all
IRQs in a disabled state in the device open path.  This allows mask
operations on the IRQ to nest within the overall enable state governed
by a valid eventfd signal.  This decouples @masked, protected by the
@locked spinlock from @trigger, protected via the @igate mutex.

In doing so, it's guaranteed that changes to @trigger cannot race the
IRQ handlers because the IRQ handler is synchronously disabled before
modifying the trigger, and loopback triggering of the IRQ via ioctl is
safe due to serialization with trigger changes via igate.

For compatibility, request_irq() failures are maintained to be local to
the SET_IRQS ioctl rather than a fatal error in the open device path.
This allows, for example, a userspace driver with polling mode support
to continue to work regardless of moving the request_irq() call site.
This necessarily blocks all SET_IRQS access to the failed index.

Cc: Eric Auger <eric.auger@redhat.com>
Cc:  <stable@vger.kernel.org>
Fixes: 57f972e2b3 ("vfio/platform: trigger an interrupt via eventfd")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-7-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:28:49 +02:00
Alex WilliamsonandGreg Kroah-Hartman 69276a555c vfio/pci: Create persistent INTx handler
commit 18c198c96a upstream.

A vulnerability exists where the eventfd for INTx signaling can be
deconfigured, which unregisters the IRQ handler but still allows
eventfds to be signaled with a NULL context through the SET_IRQS ioctl
or through unmask irqfd if the device interrupt is pending.

Ideally this could be solved with some additional locking; the igate
mutex serializes the ioctl and config space accesses, and the interrupt
handler is unregistered relative to the trigger, but the irqfd path
runs asynchronous to those.  The igate mutex cannot be acquired from the
atomic context of the eventfd wake function.  Disabling the irqfd
relative to the eventfd registration is potentially incompatible with
existing userspace.

As a result, the solution implemented here moves configuration of the
INTx interrupt handler to track the lifetime of the INTx context object
and irq_type configuration, rather than registration of a particular
trigger eventfd.  Synchronization is added between the ioctl path and
eventfd_signal() wrapper such that the eventfd trigger can be
dynamically updated relative to in-flight interrupts or irqfd callbacks.

Cc:  <stable@vger.kernel.org>
Fixes: 89e1f7d4c6 ("vfio: Add PCI device driver")
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-5-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:28:49 +02:00
Alex WilliamsonandGreg Kroah-Hartman 2ee432d740 vfio: Introduce interface to flush virqfd inject workqueue
commit b620ecbd17 upstream.

In order to synchronize changes that can affect the thread callback,
introduce an interface to force a flush of the inject workqueue.  The
irqfd pointer is only valid under spinlock, but the workqueue cannot
be flushed under spinlock.  Therefore the flush work for the irqfd is
queued under spinlock.  The vfio_irqfd_cleanup_wq workqueue is re-used
for queuing this work such that flushing the workqueue is also ordered
relative to shutdown.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-4-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Stable-dep-of: 18c198c96a ("vfio/pci: Create persistent INTx handler")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:28:49 +02:00
Alex WilliamsonandGreg Kroah-Hartman 74c564b7f0 vfio/platform: Disable virqfds on cleanup
[ Upstream commit fcdc0d3d40 ]

irqfds for mask and unmask that are not specifically disabled by the
user are leaked.  Remove any irqfds during cleanup

Cc: Eric Auger <eric.auger@redhat.com>
Cc:  <stable@vger.kernel.org>
Fixes: a7fa7c77cf ("vfio/platform: implement IRQ masking/unmasking via an eventfd")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-6-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:28:30 +02:00
Alex WilliamsonandGreg Kroah-Hartman 04a4a017b9 vfio/pci: Lock external INTx masking ops
[ Upstream commit 810cd4bb53 ]

Mask operations through config space changes to DisINTx may race INTx
configuration changes via ioctl.  Create wrappers that add locking for
paths outside of the core interrupt code.

In particular, irq_type is updated holding igate, therefore testing
is_intx() requires holding igate.  For example clearing DisINTx from
config space can otherwise race changes of the interrupt configuration.

This aligns interfaces which may trigger the INTx eventfd into two
camps, one side serialized by igate and the other only enabled while
INTx is configured.  A subsequent patch introduces synchronization for
the latter flows.

Cc:  <stable@vger.kernel.org>
Fixes: 89e1f7d4c6 ("vfio: Add PCI device driver")
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-3-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:28:30 +02:00
Alex WilliamsonandGreg Kroah-Hartman 2a4a666c45 vfio/pci: Disable auto-enable of exclusive INTx IRQ
[ Upstream commit fe9a708268 ]

Currently for devices requiring masking at the irqchip for INTx, ie.
devices without DisINTx support, the IRQ is enabled in request_irq()
and subsequently disabled as necessary to align with the masked status
flag.  This presents a window where the interrupt could fire between
these events, resulting in the IRQ incrementing the disable depth twice.
This would be unrecoverable for a user since the masked flag prevents
nested enables through vfio.

Instead, invert the logic using IRQF_NO_AUTOEN such that exclusive INTx
is never auto-enabled, then unmask as required.

Cc:  <stable@vger.kernel.org>
Fixes: 89e1f7d4c6 ("vfio: Add PCI device driver")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-2-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:28:30 +02:00
Brett CreeleyandGreg Kroah-Hartman 245c318cda vfio/pds: Always clear the save/restore FDs on reset
[ Upstream commit 8512ed2563 ]

After reset the VFIO device state will always be put in
VFIO_DEVICE_STATE_RUNNING, but the save/restore files will only be
cleared if the previous state was VFIO_DEVICE_STATE_ERROR. This
can/will cause the restore/save files to be leaked if/when the
migration state machine transitions through the states that
re-allocates these files. Fix this by always clearing the
restore/save files for resets.

Fixes: 7dabb1bcd1 ("vfio/pds: Add support for firmware recovery")
Cc: stable@vger.kernel.org
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240228003205.47311-2-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:28:23 +02:00
Joao MartinsandGreg Kroah-Hartman c99e6b267d iommufd/iova_bitmap: Consider page offset for the pages to be pinned
[ Upstream commit 4bbcbc6ea2 ]

For small bitmaps that aren't PAGE_SIZE aligned *and* that are less than
512 pages in bitmap length, use an extra page to be able to cover the
entire range e.g. [1M..3G] which would be iterated more efficiently in a
single iteration, rather than two.

Fixes: b058ea3ab5 ("vfio/iova_bitmap: refactor iova_bitmap_set() to better handle page boundaries")
Link: https://lore.kernel.org/r/20240202133415.23819-10-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:35:05 +01:00
Joao MartinsandGreg Kroah-Hartman 929766dadb iommufd/iova_bitmap: Switch iova_bitmap::bitmap to an u8 array
[ Upstream commit d18411ec30 ]

iova_bitmap_mapped_length() don't deal correctly with the small bitmaps
(< 2M bitmaps) when the starting address isn't u64 aligned, leading to
skipping a tiny part of the IOVA range. This is materialized as not
marking data dirty that should otherwise have been.

Fix that by using a u8 * in the internal state of IOVA bitmap. Most of the
data structures use the type of the bitmap to adjust its indexes, thus
changing the type of the bitmap decreases the granularity of the bitmap
indexes.

Fixes: b058ea3ab5 ("vfio/iova_bitmap: refactor iova_bitmap_set() to better handle page boundaries")
Link: https://lore.kernel.org/r/20240202133415.23819-3-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:35:05 +01:00
Joao MartinsandGreg Kroah-Hartman 634745054a iommufd/iova_bitmap: Bounds check mapped::pages access
[ Upstream commit a4ab7dedae ]

Dirty IOMMU hugepages reported on a base page page-size granularity can
lead to an attempt to set dirty pages in the bitmap beyond the limits that
are pinned.

Bounds check the page index of the array we are trying to access is within
the limits before we kmap() and return otherwise.

While it is also a defensive check, this is also in preparation to defer
setting bits (outside the mapped range) to the next iteration(s) when the
pages become available.

Fixes: b058ea3ab5 ("vfio/iova_bitmap: refactor iova_bitmap_set() to better handle page boundaries")
Link: https://lore.kernel.org/r/20240202133415.23819-2-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:35:05 +01:00
Shameer KolothumandGreg Kroah-Hartman 45f80b2f23 hisi_acc_vfio_pci: Update migration data pointer correctly on saving/resume
[ Upstream commit be12ad45e1 ]

When the optional PRE_COPY support was added to speed up the device
compatibility check, it failed to update the saving/resuming data
pointers based on the fd offset. This results in migration data
corruption and when the device gets started on the destination the
following error is reported in some cases,

[  478.907684] arm-smmu-v3 arm-smmu-v3.2.auto: event 0x10 received:
[  478.913691] arm-smmu-v3 arm-smmu-v3.2.auto:  0x0000310200000010
[  478.919603] arm-smmu-v3 arm-smmu-v3.2.auto:  0x000002088000007f
[  478.925515] arm-smmu-v3 arm-smmu-v3.2.auto:  0x0000000000000000
[  478.931425] arm-smmu-v3 arm-smmu-v3.2.auto:  0x0000000000000000
[  478.947552] hisi_zip 0000:31:00.0: qm_axi_rresp [error status=0x1] found
[  478.955930] hisi_zip 0000:31:00.0: qm_db_timeout [error status=0x400] found
[  478.955944] hisi_zip 0000:31:00.0: qm sq doorbell timeout in function 2

Fixes: d9a871e4a1 ("hisi_acc_vfio_pci: Introduce support for PRE_COPY state transitions")
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20231120091406.780-1-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:55 -08:00
Brett CreeleyandGreg Kroah-Hartman 358b1c992e vfio/pds: Fix calculations in pds_vfio_dirty_sync
[ Upstream commit 4004497cec ]

The incorrect check is being done for comparing the
iova/length being requested to sync. This can cause
the dirty sync operation to fail. Fix this by making
sure the iova offset added to the requested sync
length doesn't exceed the region_size.

Also, the region_start is assumed to always be at 0.
This can cause dirty tracking to fail because the
device/driver bitmap offset always starts at 0,
however, the region_start/iova may not. Fix this by
determining the iova offset from region_start to
determine the bitmap offset.

Fixes: f232836a91 ("vfio/pds: Add support for dirty page tracking")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20231117001207.2793-2-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:51 -08:00
Brett CreeleyandGreg Kroah-Hartman 72654bc1d4 vfio/pds: Fix possible sleep while in atomic context
[ Upstream commit ae2667cd8a ]

The driver could possibly sleep while in atomic context resulting
in the following call trace while CONFIG_DEBUG_ATOMIC_SLEEP=y is
set:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2817, name: bash
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
Call Trace:
 <TASK>
 dump_stack_lvl+0x36/0x50
 __might_resched+0x123/0x170
 mutex_lock+0x1e/0x50
 pds_vfio_put_lm_file+0x1e/0xa0 [pds_vfio_pci]
 pds_vfio_put_save_file+0x19/0x30 [pds_vfio_pci]
 pds_vfio_state_mutex_unlock+0x2e/0x80 [pds_vfio_pci]
 pci_reset_function+0x4b/0x70
 reset_store+0x5b/0xa0
 kernfs_fop_write_iter+0x137/0x1d0
 vfs_write+0x2de/0x410
 ksys_write+0x5d/0xd0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

This can happen if pds_vfio_put_restore_file() and/or
pds_vfio_put_save_file() grab the mutex_lock(&lm_file->lock)
while the spin_lock(&pds_vfio->reset_lock) is held, which can
happen during while calling pds_vfio_state_mutex_unlock().

Fix this by changing the reset_lock to reset_mutex so there are no such
conerns. Also, make sure to destroy the reset_mutex in the driver specific
VFIO device release function.

This also fixes a spinlock bad magic BUG that was caused
by not calling spinlock_init() on the reset_lock. Since, the lock is
being changed to a mutex, make sure to call mutex_init() on it.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/kvm/1f9bc27b-3de9-4891-9687-ba2820c1b390@moroto.mountain/
Fixes: bb500dbe2a ("vfio/pds: Add VFIO live migration support")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20231122192532.25791-3-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08 08:52:25 +01:00
Brett CreeleyandGreg Kroah-Hartman e9e45c1962 vfio/pds: Fix mutex lock->magic != lock warning
[ Upstream commit 91aeb563bd ]

The following BUG was found when running on a kernel with
CONFIG_DEBUG_MUTEXES=y set:

DEBUG_LOCKS_WARN_ON(lock->magic != lock)
RIP: 0010:mutex_trylock+0x10d/0x120
Call Trace:
 <TASK>
 ? __warn+0x85/0x140
 ? mutex_trylock+0x10d/0x120
 ? report_bug+0xfc/0x1e0
 ? handle_bug+0x3f/0x70
 ? exc_invalid_op+0x17/0x70
 ? asm_exc_invalid_op+0x1a/0x20
 ? mutex_trylock+0x10d/0x120
 ? mutex_trylock+0x10d/0x120
 pds_vfio_reset+0x3a/0x60 [pds_vfio_pci]
 pci_reset_function+0x4b/0x70
 reset_store+0x5b/0xa0
 kernfs_fop_write_iter+0x137/0x1d0
 vfs_write+0x2de/0x410
 ksys_write+0x5d/0xd0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

As shown, lock->magic != lock. This is because
mutex_init(&pds_vfio->state_mutex) is called in the VFIO open path. So,
if a reset is initiated before the VFIO device is opened the mutex will
have never been initialized. Fix this by calling
mutex_init(&pds_vfio->state_mutex) in the VFIO init path.

Also, don't destroy the mutex on close because the device may
be re-opened, which would cause mutex to be uninitialized. Fix this by
implementing a driver specific vfio_device_ops.release callback that
destroys the mutex before calling vfio_pci_core_release_dev().

Fixes: bb500dbe2a ("vfio/pds: Add VFIO live migration support")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20231122192532.25791-2-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08 08:52:25 +01:00
Jinjie RuanandAlex Williamson c777b11d34 vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent()
Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in
kobject_add_internal() in kobject_init_and_add() in mdev_type_add()
in parent_create_sysfs_files(), it will return 0 and probe successfully.
And when rmmod mdpy.ko, the mdpy_dev_exit() will call
mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized
parent->types[i] in parent_remove_sysfs_files(), and it will cause
below null-ptr-deref.

If mdev_type_add() fails, return the error code and kset_unregister()
to fix the issue.

 general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
 CPU: 2 PID: 10215 Comm: rmmod Tainted: G        W        N 6.6.0-rc2+ #20
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
 RIP: 0010:__kobject_del+0x62/0x1c0
 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8
 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010
 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1
 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000
 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660
 FS:  00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0
 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea
 DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? die_addr+0x3d/0xa0
  ? exc_general_protection+0x144/0x220
  ? asm_exc_general_protection+0x22/0x30
  ? __kobject_del+0x62/0x1c0
  kobject_del+0x32/0x50
  parent_remove_sysfs_files+0xd6/0x170 [mdev]
  mdev_unregister_parent+0xfb/0x190 [mdev]
  ? mdev_register_parent+0x270/0x270 [mdev]
  ? find_module_all+0x9d/0xe0
  mdpy_dev_exit+0x17/0x63 [mdpy]
  __do_sys_delete_module.constprop.0+0x2fa/0x4b0
  ? module_flags+0x300/0x300
  ? __fput+0x4e7/0xa00
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0
 RIP: 0033:0x7fbc813221b7
 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7
 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58
 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000
 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870
 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0
  </TASK>
 Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy]
 Dumping ftrace buffer:
    (ftrace buffer empty)
 ---[ end trace 0000000000000000 ]---
 RIP: 0010:__kobject_del+0x62/0x1c0
 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8
 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010
 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1
 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000
 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660
 FS:  00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0
 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea
 DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600
 PKRU: 55555554
 Kernel panic - not syncing: Fatal exception
 Dumping ftrace buffer:
    (ftrace buffer empty)
 Kernel Offset: disabled
 Rebooting in 1 seconds..

Fixes: da44c340c4 ("vfio/mdev: simplify mdev_type handling")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230918115551.1423193-1-ruanjinjie@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-09-22 12:48:04 -06:00
Shixiong OuandAlex Williamson 27004f89b0 vfio/pds: Use proper PF device access helper
The pci_physfn() helper exists to support cases where the physfn
field may not be compiled into the pci_dev structure. We've
declared this driver dependent on PCI_IOV to avoid this problem,
but regardless we should follow the precedent not to access this
field directly.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230914021332.1929155-1-oushixiong@kylinos.cn
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-09-18 13:36:53 -06:00
Shixiong OuandAlex Williamson 5a59f2ff30 vfio/pds: Add missing PCI_IOV depends
If PCI_ATS isn't set, then pdev->physfn is not defined.
it causes a compilation issue:

../drivers/vfio/pci/pds/vfio_dev.c:165:30: error: ‘struct pci_dev’ has no member named ‘physfn’; did you mean ‘is_physfn’?
  165 |   __func__, pci_dev_id(pdev->physfn), pci_id, vf_id,
      |                              ^~~~~~

So adding PCI_IOV depends to select PCI_ATS.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230906014942.1658769-1-oushixiong@kylinos.cn
Fixes: 63f77a7161 ("vfio/pds: register with the pds_core PF")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-09-18 13:36:52 -06:00
Linus Torvalds 4debf77169 Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd
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
  ...
2023-08-30 20:41:37 -07:00
Linus Torvalds ec0e2dc810 Merge tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio
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()
  ...
2023-08-30 20:36:01 -07:00
Brett CreeleyandAlex Williamson 642265e22e vfio/pds: Send type for SUSPEND_STATUS command
Commit bb500dbe2a ("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: bb500dbe2a ("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>
2023-08-22 13:11:57 -06:00
Yang YingliangandAlex Williamson 2d12d18f14 vfio/pds: fix return value in pds_vfio_get_lm_file()
anon_inode_getfile() never returns NULL pointer, it will return
ERR_PTR() when it fails, so replace the check with IS_ERR().

Fixes: bb500dbe2a ("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>
2023-08-21 08:50:33 -06:00
Stefan HajnocziandAlex Williamson a881b49694 vfio: align capability structures
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>
2023-08-17 12:17:44 -06:00
Stefan HajnocziandAlex Williamson cd24e2a60a vfio/type1: fix cap_migration information leak
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: ad721705d0 ("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>
2023-08-16 12:25:35 -06:00
Li ZetaoandAlex Williamson 6c092088fa vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code
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>
2023-08-16 11:14:15 -06:00
Li ZetaoandAlex Williamson d7955ce40e vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver
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>
2023-08-16 11:13:51 -06:00