linux-stable.git/drivers/vhost, branch v6.9.2

vhost: correct misleading printing information

2024-04-08T08:11:04+00:00

Guest moved avail idx not used idx when we need to print log if
'(vq->avail_idx - last_avail_idx) > vq->num', so fix it.

Signed-off-by: Xianting Tian 
Message-Id: <20240311082109.46773-1-xianting.tian@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin

vhost: Add smp_rmb() in vhost_enable_notify()

2024-04-08T08:11:04+00:00

A smp_rmb() has been missed in vhost_enable_notify(), inspired by
Will. Otherwise, it's not ensured the available ring entries pushed
by guest can be observed by vhost in time, leading to stale available
ring entries fetched by vhost in vhost_get_vq_desc(), as reported by
Yihuang Yu on NVidia's grace-hopper (ARM64) platform.

  /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64      \
  -accel kvm -machine virt,gic-version=host -cpu host          \
  -smp maxcpus=1,cpus=1,sockets=1,clusters=1,cores=1,threads=1 \
  -m 4096M,slots=16,maxmem=64G                                 \
  -object memory-backend-ram,id=mem0,size=4096M                \
   :                                                           \
  -netdev tap,id=vnet0,vhost=true                              \
  -device virtio-net-pci,bus=pcie.8,netdev=vnet0,mac=52:54:00:f1:26:b0
   :
  guest# netperf -H 10.26.1.81 -l 60 -C -c -t UDP_STREAM
  virtio_net virtio0: output.0:id 100 is not a head!

Add the missed smp_rmb() in vhost_enable_notify(). When it returns true,
it means there's still pending tx buffers. Since it might read indices,
so it still can bypass the smp_rmb() in vhost_get_vq_desc(). Note that
it should be safe until vq->avail_idx is changed by commit d3bb267bbdcb
("vhost: cache avail index in vhost_enable_notify()").

Fixes: d3bb267bbdcb ("vhost: cache avail index in vhost_enable_notify()")
Cc:  # v5.18+
Reported-by: Yihuang Yu 
Suggested-by: Will Deacon 
Signed-off-by: Gavin Shan 
Acked-by: Jason Wang 
Message-Id: <20240328002149.1141302-3-gshan@redhat.com>
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefano Garzarella

vhost: Add smp_rmb() in vhost_vq_avail_empty()

2024-04-08T08:11:04+00:00

A smp_rmb() has been missed in vhost_vq_avail_empty(), spotted by
Will. Otherwise, it's not ensured the available ring entries pushed
by guest can be observed by vhost in time, leading to stale available
ring entries fetched by vhost in vhost_get_vq_desc(), as reported by
Yihuang Yu on NVidia's grace-hopper (ARM64) platform.

  /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64      \
  -accel kvm -machine virt,gic-version=host -cpu host          \
  -smp maxcpus=1,cpus=1,sockets=1,clusters=1,cores=1,threads=1 \
  -m 4096M,slots=16,maxmem=64G                                 \
  -object memory-backend-ram,id=mem0,size=4096M                \
   :                                                           \
  -netdev tap,id=vnet0,vhost=true                              \
  -device virtio-net-pci,bus=pcie.8,netdev=vnet0,mac=52:54:00:f1:26:b0
   :
  guest# netperf -H 10.26.1.81 -l 60 -C -c -t UDP_STREAM
  virtio_net virtio0: output.0:id 100 is not a head!

Add the missed smp_rmb() in vhost_vq_avail_empty(). When tx_can_batch()
returns true, it means there's still pending tx buffers. Since it might
read indices, so it still can bypass the smp_rmb() in vhost_get_vq_desc().
Note that it should be safe until vq->avail_idx is changed by commit
275bf960ac697 ("vhost: better detection of available buffers").

Fixes: 275bf960ac69 ("vhost: better detection of available buffers")
Cc:  # v4.11+
Reported-by: Yihuang Yu 
Suggested-by: Will Deacon 
Signed-off-by: Gavin Shan 
Acked-by: Jason Wang 
Message-Id: <20240328002149.1141302-2-gshan@redhat.com>
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefano Garzarella

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

2024-03-19T15:57:39+00:00

Pull virtio updates from Michael Tsirkin:

 - Per vq sizes in vdpa

 - Info query for block devices support in vdpa

 - DMA sync callbacks in vduse

 - Fixes, cleanups

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (35 commits)
  virtio_net: rename free_old_xmit_skbs to free_old_xmit
  virtio_net: unify the code for recycling the xmit ptr
  virtio-net: add cond_resched() to the command waiting loop
  virtio-net: convert rx mode setting to use workqueue
  virtio: packed: fix unmap leak for indirect desc table
  vDPA: report virtio-blk flush info to user space
  vDPA: report virtio-block read-only info to user space
  vDPA: report virtio-block write zeroes configuration to user space
  vDPA: report virtio-block discarding configuration to user space
  vDPA: report virtio-block topology info to user space
  vDPA: report virtio-block MQ info to user space
  vDPA: report virtio-block max segments in a request to user space
  vDPA: report virtio-block block-size to user space
  vDPA: report virtio-block max segment size to user space
  vDPA: report virtio-block capacity to user space
  virtio: make virtio_bus const
  vdpa: make vdpa_bus const
  vDPA/ifcvf: implement vdpa_config_ops.get_vq_num_min
  vDPA/ifcvf: get_max_vq_size to return max size
  virtio_vdpa: create vqs with the actual size
  ...

vDPA: introduce get_vq_size to vdpa_config_ops

2024-03-19T06:45:50+00:00

This commit introduces a new interface get_vq_size to
vDPA config ops, this new interface intends to report
the size of a specific virtqueue

Signed-off-by: Zhu Lingshan 
Message-Id: <20240202163905.8834-3-lingshan.zhu@intel.com>
Signed-off-by: Michael S. Tsirkin

vdpa: skip suspend/resume ops if not DRIVER_OK

2024-03-19T06:45:49+00:00

If a vdpa device is not in state DRIVER_OK, then there is no driver state
to preserve, so no need to call the suspend and resume driver ops.

Suggested-by: Eugenio Perez Martin "
Signed-off-by: Steve Sistare 
Message-Id: <1707834358-165470-1-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Eugenio Pérez

vhost: Added pad cleanup if vnet_hdr is not present.

2024-03-19T06:45:49+00:00

When the Qemu launched with vhost but without tap vnet_hdr,
vhost tries to copy vnet_hdr from socket iter with size 0
to the page that may contain some trash.
That trash can be interpreted as unpredictable values for
vnet_hdr.
That leads to dropping some packets and in some cases to
stalling vhost routine when the vhost_net tries to process
packets and fails in a loop.

Qemu options:
  -netdev tap,vhost=on,vnet_hdr=off,...

Signed-off-by: Andrew Melnychenko 
Message-Id: <20240115194840.1183077-1-andrew@daynix.com>
Signed-off-by: Michael S. Tsirkin

vhost/net: remove vhost_net_page_frag_refill()

2024-03-05T10:38:14+00:00

The page frag in vhost_net_page_frag_refill() uses the
'struct page_frag' from skb_page_frag_refill(), but it's
implementation is similar to page_frag_alloc_align() now.

This patch removes vhost_net_page_frag_refill() by using
'struct page_frag_cache' instead of 'struct page_frag',
and allocating frag using page_frag_alloc_align().

The added benefit is that not only unifying the page frag
implementation a little, but also having about 0.5% performance
boost testing by using the vhost_net_test introduced in the
last patch.

Signed-off-by: Yunsheng Lin 
Acked-by: Jason Wang 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Paolo Abeni

page_frag: unify gfp bits for order 3 page allocation

2024-03-05T10:38:14+00:00

Currently there seems to be three page frag implementations
which all try to allocate order 3 page, if that fails, it
then fail back to allocate order 0 page, and each of them
all allow order 3 page allocation to fail under certain
condition by using specific gfp bits.

The gfp bits for order 3 page allocation are different
between different implementation, __GFP_NOMEMALLOC is
or'd to forbid access to emergency reserves memory for
__page_frag_cache_refill(), but it is not or'd in other
implementions, __GFP_DIRECT_RECLAIM is masked off to avoid
direct reclaim in vhost_net_page_frag_refill(), but it is
not masked off in __page_frag_cache_refill().

This patch unifies the gfp bits used between different
implementions by or'ing __GFP_NOMEMALLOC and masking off
__GFP_DIRECT_RECLAIM for order 3 page allocation to avoid
possible pressure for mm.

Leave the gfp unifying for page frag implementation in sock.c
for now as suggested by Paolo Abeni.

Signed-off-by: Yunsheng Lin 
Reviewed-by: Alexander Duyck 
CC: Alexander Duyck 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Paolo Abeni

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

2024-01-19T00:44:03+00:00

Pull virtio updates from Michael Tsirkin:

 - vdpa/mlx5: support for resumable vqs

 - virtio_scsi: mq_poll support

 - 3virtio_pmem: support SHMEM_REGION

 - virtio_balloon: stay awake while adjusting balloon

 - virtio: support for no-reset virtio PCI PM

 - Fixes, cleanups

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vdpa/mlx5: Add mkey leak detection
  vdpa/mlx5: Introduce reference counting to mrs
  vdpa/mlx5: Use vq suspend/resume during .set_map
  vdpa/mlx5: Mark vq state for modification in hw vq
  vdpa/mlx5: Mark vq addrs for modification in hw vq
  vdpa/mlx5: Introduce per vq and device resume
  vdpa/mlx5: Allow modifying multiple vq fields in one modify command
  vdpa/mlx5: Expose resumable vq capability
  vdpa: Block vq property changes in DRIVER_OK
  vdpa: Track device suspended state
  scsi: virtio_scsi: Add mq_poll support
  virtio_pmem: support feature SHMEM_REGION
  virtio_balloon: stay awake while adjusting balloon
  vdpa: Remove usage of the deprecated ida_simple_xx() API
  virtio: Add support for no-reset virtio PCI PM
  virtio_net: fix missing dma unmap for resize
  vhost-vdpa: account iommu allocations
  vdpa: Fix an error handling path in eni_vdpa_probe()