commit 4fa59ede95 upstream.
The feature negotiation was designed in a way that
makes it possible for devices to know which config
fields will be accessed by drivers.
This is broken since commit 404123c2db ("virtio: allow drivers to
validate features") with fallout in at least block and net. We have a
partial work-around in commit 2f9a174f91 ("virtio: write back
F_VERSION_1 before validate") which at least lets devices find out which
format should config space have, but this is a partial fix: guests
should not access config space without acknowledging features since
otherwise we'll never be able to change the config space format.
To fix, split finalize_features from virtio_finalize_features and
call finalize_features with all feature bits before validation,
and then - if validation changed any bits - once again after.
Since virtio_finalize_features no longer writes out features
rename it to virtio_features_ok - since that is what it does:
checks that features are ok with the device.
As a side effect, this also reduces the amount of hypervisor accesses -
we now only acknowledge features once unless we are clearing any
features when validating (which is uncommon).
IRC I think that this was more or less always the intent in the spec but
unfortunately the way the spec is worded does not say this explicitly, I
plan to address this at the spec level, too.
Acked-by: Jason Wang <jasowang@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 404123c2db ("virtio: allow drivers to validate features")
Fixes: 2f9a174f91 ("virtio: write back F_VERSION_1 before validate")
Cc: "Halil Pasic" <pasic@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1861ba626a upstream.
A recently added error path does not mark ring unused when exiting on
OOM, which will lead to BUG on the next entry in debug builds.
TODO: refactor code so we have START_USE and END_USE in the same function.
Fixes: fc6d70f40b ("virtio_ring: check desc == NULL when using indirect with packed")
Cc: "Xuan Zhuo" <xuanzhuo@linux.alibaba.com>
Cc: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 817fc978b5 upstream.
virtio_max_dma_size() returns the maximum DMA mapping size of the virtio
device by querying dma_max_mapping_size() for the device when the DMA
API is in use for the vring. Unfortunately, the device passed is
initialised by register_virtio_device() and does not inherit the DMA
configuration from its parent, resulting in SWIOTLB errors when bouncing
is enabled and the default 256K mapping limit (IO_TLB_SEGSIZE) is not
respected:
| virtio-pci 0000:00:01.0: swiotlb buffer is full (sz: 294912 bytes), total 1024 (slots), used 725 (slots)
Follow the pattern used elsewhere in the virtio_ring code when calling
into the DMA layer and pass the parent device to dma_max_mapping_size()
instead.
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20211201112018.25276-1-will@kernel.org
Acked-by: Jason Wang <jasowang@redhat.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes: e6d6dd6c87 ("virtio: Introduce virtio_max_dma_size()")
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2f9a174f91 upstream.
The virtio specification virtio-v1.1-cs01 states: "Transitional devices
MUST detect Legacy drivers by detecting that VIRTIO_F_VERSION_1 has not
been acknowledged by the driver." This is exactly what QEMU as of 6.1
has done relying solely on VIRTIO_F_VERSION_1 for detecting that.
However, the specification also says: "... the driver MAY read (but MUST
NOT write) the device-specific configuration fields to check that it can
support the device ..." before setting FEATURES_OK.
In that case, any transitional device relying solely on
VIRTIO_F_VERSION_1 for detecting legacy drivers will return data in
legacy format. In particular, this implies that it is in big endian
format for big endian guests. This naturally confuses the driver which
expects little endian in the modern mode.
It is probably a good idea to amend the spec to clarify that
VIRTIO_F_VERSION_1 can only be relied on after the feature negotiation
is complete. Before validate callback existed, config space was only
read after FEATURES_OK. However, we already have two regressions, so
let's address this here as well.
The regressions affect the VIRTIO_NET_F_MTU feature of virtio-net and
the VIRTIO_BLK_F_BLK_SIZE feature of virtio-blk for BE guests when
virtio 1.0 is used on both sides. The latter renders virtio-blk unusable
with DASD backing, because things simply don't work with the default.
See Fixes tags for relevant commits.
For QEMU, we can work around the issue by writing out the feature bits
with VIRTIO_F_VERSION_1 bit set. We (ab)use the finalize_features
config op for this. This isn't enough to address all vhost devices since
these do not get the features until FEATURES_OK, however it looks like
the affected devices actually never handled the endianness for legacy
mode correctly, so at least that's not a regression.
No devices except virtio net and virtio blk seem to be affected.
Long term the right thing to do is to fix the hypervisors.
Cc: <stable@vger.kernel.org> #v4.11
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Fixes: 82e89ea077 ("virtio-blk: Add validation for block size in config space")
Fixes: fe36cbe067 ("virtio_net: clear MTU when out of range")
Reported-by: markver@us.ibm.com
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20211011053921.1198936-1-pasic@linux.ibm.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 43bb40c5b9 ]
When a virtio pci device undergo surprise removal (aka async removal in
PCIe spec), mark the device as broken so that any upper layer drivers can
abort any outstanding operation.
When a virtio net pci device undergo surprise removal which is used by a
NetworkManager, a below call trace was observed.
kernel:watchdog: BUG: soft lockup - CPU#1 stuck for 26s! [kworker/1:1:27059]
watchdog: BUG: soft lockup - CPU#1 stuck for 52s! [kworker/1:1:27059]
CPU: 1 PID: 27059 Comm: kworker/1:1 Tainted: G S W I L 5.13.0-hotplug+ #8
Hardware name: Dell Inc. PowerEdge R640/0H28RR, BIOS 2.9.4 11/06/2020
Workqueue: events linkwatch_event
RIP: 0010:virtnet_send_command+0xfc/0x150 [virtio_net]
Call Trace:
virtnet_set_rx_mode+0xcf/0x2a7 [virtio_net]
? __hw_addr_create_ex+0x85/0xc0
__dev_mc_add+0x72/0x80
igmp6_group_added+0xa7/0xd0
ipv6_mc_up+0x3c/0x60
ipv6_find_idev+0x36/0x80
addrconf_add_dev+0x1e/0xa0
addrconf_dev_config+0x71/0x130
addrconf_notify+0x1f5/0xb40
? rtnl_is_locked+0x11/0x20
? __switch_to_asm+0x42/0x70
? finish_task_switch+0xaf/0x2c0
? raw_notifier_call_chain+0x3e/0x50
raw_notifier_call_chain+0x3e/0x50
netdev_state_change+0x67/0x90
linkwatch_do_dev+0x3c/0x50
__linkwatch_run_queue+0xd2/0x220
linkwatch_event+0x21/0x30
process_one_work+0x1c8/0x370
worker_thread+0x30/0x380
? process_one_work+0x370/0x370
kthread+0x118/0x140
? set_kthread_struct+0x40/0x40
ret_from_fork+0x1f/0x30
Hence, add the ability to abort the command on surprise removal
which prevents infinite loop and system lockup.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Link: https://lore.kernel.org/r/20210721142648.1525924-5-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 60f0779862 ]
Currently vq->broken field is read by virtqueue_is_broken() in busy
loop in one context by virtnet_send_command().
vq->broken is set to true in other process context by
virtio_break_device(). Reader and writer are accessing it without any
synchronization. This may lead to a compiler optimization which may
result to optimize reading vq->broken only once.
Hence, force reading vq->broken on each invocation of
virtqueue_is_broken() and also force writing it so that such
update is visible to the readers.
It is a theoretical fix that isn't yet encountered in the field.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Link: https://lore.kernel.org/r/20210721142648.1525924-2-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Pull virtio updates from Michael Tsirkin:
"vhost, vdpa, and virtio cleanups and fixes
A very quiet cycle, no new features"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
MAINTAINERS: add URL for virtio-mem
vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call
vringh: fix __vringh_iov() when riov and wiov are different
vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK
s390: virtio: PV needs VIRTIO I/O device protection
virtio: let arch advertise guest's memory access restrictions
vhost_vdpa: Fix duplicate included kernel.h
vhost: reduce stack usage in log_used
virtio-mem: Constify mem_id_table
virtio_input: Constify id_table
virtio-balloon: Constify id_table
vdpa/mlx5: Fix failure to bring link up
vdpa/mlx5: Make use of a specific 16 bit endianness API
An architecture may restrict host access to guest memory,
e.g. IBM s390 Secure Execution or AMD SEV.
Provide a new Kconfig entry the architecture can select,
CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, when it provides
the arch_has_restricted_virtio_memory_access callback to advertise
to VIRTIO common code when the architecture restricts memory access
from the host.
The common code can then fail the probe for any device where
VIRTIO_F_ACCESS_PLATFORM is required, but not set.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/1599728030-17085-2-git-send-email-pmorel@linux.ibm.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Pull drm updates from Dave Airlie:
"Not a major amount of change, the i915 trees got split into display
and gt trees to better facilitate higher level review, and there's a
major refactoring of i915 GEM locking to use more core kernel concepts
(like ww-mutexes). msm gets per-process pagetables, older AMD SI cards
get DC support, nouveau got a bump in displayport support with common
code extraction from i915.
Outside of drm this contains a couple of patches for hexint
moduleparams which you've acked, and a virtio common code tree that
you should also get via it's regular path.
New driver:
- Cadence MHDP8546 DisplayPort bridge driver
core:
- cross-driver scatterlist cleanups
- devm_drm conversions
- remove drm_dev_init
- devm_drm_dev_alloc conversion
ttm:
- lots of refactoring and cleanups
bridges:
- chained bridge support in more drivers
panel:
- misc new panels
scheduler:
- cleanup priority levels
displayport:
- refactor i915 code into helpers for nouveau
i915:
- split into display and GT trees
- WW locking refactoring in GEM
- execbuf2 extension mechanism
- syncobj timeline support
- GEN 12 HOBL display powersaving
- Rocket Lake display additions
- Disable FBC on Tigerlake
- Tigerlake Type-C + DP improvements
- Hotplug interrupt refactoring
amdgpu:
- Sienna Cichlid updates
- Navy Flounder updates
- DCE6 (SI) support for DC
- Plane rotation enabled
- TMZ state info ioctl
- PCIe DPC recovery support
- DC interrupt handling refactor
- OLED panel fixes
amdkfd:
- add SMI events for thermal throttling
- SMI interface events ioctl update
- process eviction counters
radeon:
- move to dma_ for allocations
- expose sclk via sysfs
msm:
- DSI support for sm8150/sm8250
- per-process GPU pagetable support
- Displayport support
mediatek:
- move HDMI phy driver to PHY
- convert mtk-dpi to bridge API
- disable mt2701 tmds
tegra:
- bridge support
exynos:
- misc cleanups
vc4:
- dual display cleanups
ast:
- cleanups
gma500:
- conversion to GPIOd API
hisilicon:
- misc reworks
ingenic:
- clock handling and format improvements
mcde:
- DSI support
mgag200:
- desktop g200 support
mxsfb:
- i.MX7 + i.MX8M
- alpha plane support
panfrost:
- devfreq support
- amlogic SoC support
ps8640:
- EDID from eDP retrieval
tidss:
- AM65xx YUV workaround
virtio:
- virtio-gpu exported resources
rcar-du:
- R8A7742, R8A774E1 and R8A77961 support
- YUV planar format fixes
- non-visible plane handling
- VSP device reference count fix
- Kconfig fix to avoid displaying disabled options in .config"
* tag 'drm-next-2020-10-15' of git://anongit.freedesktop.org/drm/drm: (1494 commits)
drm/ingenic: Fix bad revert
drm/amdgpu: Fix invalid number of character '{' in amdgpu_acpi_init
drm/amdgpu: Remove warning for virtual_display
drm/amdgpu: kfd_initialized can be static
drm/amd/pm: setup APU dpm clock table in SMU HW initialization
drm/amdgpu: prevent spurious warning
drm/amdgpu/swsmu: fix ARC build errors
drm/amd/display: Fix OPTC_DATA_FORMAT programming
drm/amd/display: Don't allow pstate if no support in blank
drm/panfrost: increase readl_relaxed_poll_timeout values
MAINTAINERS: Update entry for st7703 driver after the rename
Revert "gpu/drm: ingenic: Add option to mmap GEM buffers cached"
drm/amd/display: HDMI remote sink need mode validation for Linux
drm/amd/display: Change to correct unit on audio rate
drm/amd/display: Avoid set zero in the requested clk
drm/amdgpu: align frag_end to covered address space
drm/amdgpu: fix NULL pointer dereference for Renoir
drm/vmwgfx: fix regression in thp code due to ttm init refactor.
drm/amdgpu/swsmu: add interrupt work handler for smu11 parts
drm/amdgpu/swsmu: add interrupt work function
...
When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather
unclear, which is why we special-cased ZONE_MOVABLE such that partially
plugged blocks would never end up in ZONE_MOVABLE.
Now that the semantics are much clearer (and will be documented in a
follow-up patch including the new virtio-mem behavior), let's allow to
online partially plugged memory blocks to ZONE_MOVABLE and also consider
memory blocks that were onlined to ZONE_MOVABLE when unplugging memory.
While unplugged memory pages are, in general, unmovable, they can be
skipped when offlining memory.
virtio-mem only unplugs fairly big chunks (in the megabyte range) and
rather tries to shrink the memory region than randomly choosing memory.
In theory, if all other pages in the movable zone would be movable,
virtio-mem would only shrink that zone and not create any kind of
fragmentation.
In the future, we might want to remember the zone again and use the
information when (un)plugging memory. For now, let's keep it simple.
Note: Support for defragmentation is planned, to deal with fragmentation
after unplug due to memory chunks within memory blocks that could not get
unplugged before (e.g., somebody pinning pages within ZONE_MOVABLE for a
longer time).
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200816125333.7434-6-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>