linux-stable.git/drivers/vhost, branch master

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2026-08-21T00:07:50+00:00

Pull vhost,vdpa,virtio updates from Michael Tsirkin:

 - transport v3 support in virtio-mmio

 - suspend support in vduse

 - fixes, cleanups all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (54 commits)
  vduse: Add suspend
  vduse: do not take rwsem at reset work flush
  vduse: add F_QUEUE_READY feature
  vduse: add VDUSE_SET_FEATURES ioctl
  vduse: add VDUSE_GET_FEATURES ioctl
  vduse: store control device pointer
  tools/virtio: Fix control typo in trace agent comment
  tools/virtio: Fix userspace typo in vringh test comment
  vhost: reject zero-size IOTLB INVALIDATE
  vdpa: Remove redundant dev_err()
  virtio_ring: fix infinite loop in virtnet_poll_cleantx when device is broken
  vdpa/mlx5: roll back MR update after VQ setup failure
  MAINTAINERS: remove Gabriel from LiteX and fw-cfg drivers
  virtio_mem: fix typo in comment
  vdpa/solidrun: fix typos in snet_ctrl comments
  virtio: fix article before virtio in dma-buf comment
  vhost: fix inaccurate kdoc in iotlb helpers
  virtio: rtc: time out alarm requests
  vdpa/mlx5: fix wrong MLX5_ADDR_OF struct type in alloc_inout()
  vdpa: octeon_ep: add missing MODULE_DEVICE_TABLE()
  ...

vhost: reject zero-size IOTLB INVALIDATE

2026-08-19T10:38:47+00:00

Reject VHOST_IOTLB_INVALIDATE messages with size == 0 to prevent
iova + size - 1 from underflowing to U64_MAX, which would
incorrectly delete the entire IOTLB.

Signed-off-by: xiongweimin 
Signed-off-by: Michael S. Tsirkin 
Message-ID: <20260716030236.124322-1-xiongwm2026@163.com>

vhost: fix inaccurate kdoc in iotlb helpers

2026-08-19T10:38:47+00:00

Correct missing "if" in the add_range_ctx return description, and
align vhost_iotlb_alloc documentation with its NULL return on
allocation failure.

Signed-off-by: xiongweimin 
Signed-off-by: Michael S. Tsirkin 
Message-ID: <20260714024434.188302-1-15927021679@163.com>

vhost/net: fix clear_user start address in VHOST_GET_FEATURES_ARRAY

2026-08-19T10:38:45+00:00

The clear_user() call in VHOST_GET_FEATURES_ARRAY incorrectly starts
at argp, which is the beginning of the features array, overwriting the
data just written by copy_to_user(). It should start after the copied
elements at argp + copied * sizeof(u64) to only zero the trailing
unused space.

Use size_mul() for both the offset and length calculations so the
arithmetic stays consistent with the surrounding code and remains
overflow-safe.

Fixes: 333c515d1896 ("vhost-net: allow configuring extended features")
Signed-off-by: Yufeng Wang 
Acked-by: Eugenio Pérez 
Signed-off-by: Michael S. Tsirkin 
Message-ID: <20260626070438.59149-1-r4o5m6e8o@163.com>

vhost-net: wake queue of tun/tap after ptr_ring consume

2026-08-08T00:29:15+00:00

Add tun_wake_queue() to tun.c and export it for use by vhost-net. The
function validates that the file belongs to a device implemented by
drivers/net/tun.c, in IFF_TUN as well as in IFF_TAP mode, and that the
tfile exists, dereferences the tun_struct under RCU, and delegates to
__tun_wake_queue().

vhost_net_buf_produce() now calls tun_wake_queue() after a successful
batched consume of the ring to allow the netdev subqueue to be woken up.
The point is to allow the queue to be stopped when it gets full, which is
required for traffic shaping, implemented by the following
"stop tail-drop when IFF_BACKPRESSURE is set".
As __tun_wake_queue() returns early unless IFF_BACKPRESSURE is set, a
tun/tap device that does not opt in only pays for the added check.

macvtap and ipvtap rings, which get_tap_ptr_ring() accepts too, are
unaffected: their producer is the tap_handle_frame() rx_handler and not
ndo_start_xmit, so stopping a netdev TX queue would not hold it back.
drivers/net/tap.c has no netdev_ops of its own either. No
tap_wake_queue() is needed.

cons_cnt and the wake decision are best-effort and are not reverted by
ptr_ring_unconsume(), so vhost_net_buf_unproduce() can leave the subqueue
woken over a full ring. The producer re-stops it on the next packet, and
that path only runs from vhost_net_stop_vq() and vhost_net_set_backend(),
when the consumer is going away, so a stopped queue is the correct end
state rather than a stall.

Co-developed-by: Tim Gebauer 
Signed-off-by: Tim Gebauer 
Signed-off-by: Simon Schippers 
Link: https://patch.msgid.link/20260803183641.96882-4-simon.schippers@tu-dortmund.de
Signed-off-by: Jakub Kicinski

vhost-scsi: reject feature changes after endpoint

2026-08-04T03:08:15+00:00

vhost_scsi_setup_vq_cmds() runs from VHOST_SCSI_SET_ENDPOINT and allocates
each command's protection scatterlist array (prot_sgl) according to the
acknowledged VIRTIO_SCSI_F_T10_PI bit.  The command pools are not rebuilt
when VHOST_SET_FEATURES changes that bit later.

Although virtio feature bits must not change after feature negotiation,
vhost_scsi_set_features() currently accepts such a request after the
endpoint is active and updates acked_features.  Enabling T10-PI after
endpoint setup therefore leaves prot_sgl NULL while the I/O path follows
the new feature bit.

For a 129-page protection payload, vhost_scsi_mapal() passes the missing
first chunk to sg_alloc_table_chained():

  sg_alloc_table_chained(table, 129, first_chunk=NULL,
                         nents_first_chunk=inline_sg_cnt)

sg_pool_index() then hits:

  BUG_ON(nents > SG_CHUNK_SIZE);   /* 129 > 128 */

The kernel reported the following call trace and register state:

  Call Trace:
   
   ? __sg_alloc_table+0x1d8/0x250
   ? __pfx_vhost_run_work_list+0x10/0x10 [vhost]
   sg_alloc_table_chained+0x59/0xf0
   ? __pfx_sg_pool_alloc+0x10/0x10
   ? vhost_scsi_calc_sgls.constprop.0+0x43/0x60 [vhost_scsi]
   vhost_scsi_handle_vq+0xf02/0x1700 [vhost_scsi]
   ? __pfx_vhost_scsi_handle_vq+0x10/0x10 [vhost_scsi]
   vhost_scsi_handle_kick+0x37/0x50 [vhost_scsi]
   vhost_run_work_list+0x8e/0xd0 [vhost]
   vhost_task_fn+0xe1/0x210
   ret_from_fork+0x348/0x540
   

  RIP: 0010:0x4
  CR2 = 0x4
  RSP: 0018:ffffc90000dbf940 EFLAGS: 00010202
  RAX: ffffffff82396810 RBX: ffff88811dc28b80 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000820 RDI: 0000000000000081

VHOST_F_LOG_ALL is a vhost-specific runtime feature and remains the only
exception.

Reject changes to any feature other than VHOST_F_LOG_ALL while the
endpoint is active.  This preserves the existing runtime log toggle while
preventing feature-dependent command resources and data-path state from
becoming inconsistent.  Userspace must clear the endpoint before changing
any other negotiated feature and set the endpoint up again afterward.

Fixes: bf2d650391be ("vhost-scsi: Allocate T10 PI structs only when enabled")
Signed-off-by: Jia Jia 
Reviewed-by: Stefan Hajnoczi 
Signed-off-by: Michael S. Tsirkin 
Message-ID: <20260726144314.1652934-1-physicalmtea@gmail.com>

vhost-scsi: flush backend after device ioctls

2026-08-04T03:08:15+00:00

vhost-scsi translates guest response descriptors into userspace iovecs
when commands are submitted.  Target-core completes those commands
asynchronously, so VHOST_SET_MEM_TABLE can replace the memory table while
an in-flight command still retains response iovecs translated through the
old table.

If the old mapping is reused after VHOST_SET_MEM_TABLE returns, command
completion can write the response to an unrelated userspace object.

Flush the vhost-scsi backend after vhost_dev_ioctl() handles a device
ioctl.  This waits for in-flight commands that can still use the old
response iovecs before the ioctl returns.

Signed-off-by: Jia Jia 
Signed-off-by: Michael S. Tsirkin 
Message-ID: <20260724060919.1569170-1-physicalmtea@gmail.com>

vhost: reset the vring metadata cache on vring reconfiguration

2026-08-04T03:08:15+00:00

vq->meta_iotlb[] caches the vhost_iotlb_map that backs each vring
metadata region, and iotlb_access_ok() returns early on a cache hit,
taking the hit as proof that the region has already been validated:

	if (vhost_vq_meta_fetch(vq, addr, len, type))
		return true;

The cache is reset on VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE, on
device IOTLB (re)initialisation and on vq reset, but not when
VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail and vq->used, nor when
VHOST_SET_VRING_NUM changes the region sizes.

With a device IOTLB attached both ioctls are accepted while the vq is
live, and neither validates the addresses at ioctl time: vq_access_ok()
and vq_log_used_access_ok() return true early because the addresses are
GIOVAs, deferring validation to prefetch time.  Once the cache has been
populated that deferred validation no longer runs -- vq_meta_prefetch()
hits the stale entry and returns true -- and vhost_vq_meta_fetch() keeps
translating through the old mapping as

	map->addr + addr - map->start

for an address the mapping no longer covers.  vhost_copy_to_user() and
vhost_copy_from_user() consume the result with __copy_to_user() and
__copy_from_user(), which do not check it either, so a subsequent used
ring update or descriptor fetch accesses memory outside the region the
IOTLB actually maps.

Reset the metadata cache whenever the vring is reconfigured, so the new
addresses are pushed back through iotlb_access_ok()'s slow path.

Fixes: f88949138058 ("vhost: introduce O(1) vq metadata cache")
Cc: stable@vger.kernel.org
Assisted-by: tencentos-corvus-ai:kimi-k3
Signed-off-by: Jun Yang 
Message-ID: <20260803014823.68623-1-juny24602@gmail.com>
Signed-off-by: Michael S. Tsirkin

vhost-scsi: Validate T10 PI scatterlist counts

2026-08-04T03:08:15+00:00

When T10 PI is negotiated, vhost-scsi splits protection bytes from
the data iterator before mapping the request scatterlists. A malformed
request can claim protection bytes that cover or exceed the full payload
length. The former leaves no data bytes to map, while the latter
underflows exp_data_len before advancing the iterator. Both cases can let
a zero data SGL count reach sg_alloc_table_chained(), which triggers
BUG_ON(!nents).

Reject protection lengths that cover or exceed the payload before
subtracting prot_bytes and advancing the iterator. Also propagate
negative errors from the protection SGL calculation before calling the
allocator, matching the data SGL path.

Fixes: bca939d5bcd0 ("vhost-scsi: Dynamically allocate scatterlists")
Suggested-by: Jia Jia 
Signed-off-by: Jia Jia 
Assisted-by: OpenAI-Codex:GPT-5
Signed-off-by: Linfeng Sun 
Message-ID: <20260727081841.923151-1-slf@hdu.edu.cn>
Signed-off-by: Michael S. Tsirkin

vhost/vdpa: reject overflowing PA map page counts on 32-bit

2026-08-03T19:21:54+00:00

vhost_vdpa_pa_map() adds the IOVA page offset to the user-controlled map
size before computing the number of pages to pin. On 32-bit systems,
where unsigned long is narrower than u64, that addition can overflow and
the code can pin and map fewer pages than the requested IOTLB range.

Reject sizes that overflow the unsigned long page-count calculation.

Fixes: 22af48cf91aa ("vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap()")
Acked-by: Michael S. Tsirkin 
Signed-off-by: Yousef Alhouseen 
Signed-off-by: Michael S. Tsirkin 
Message-ID: