Virtio devices might lose their state when the VMM is restarted
after a suspend to disk (hibernation) cycle. This means that the
guest page size register must be restored for the virtio_mmio legacy
interface, since otherwise the virtio queues are not functional.
This is particularly problematic for QEMU that currently still defaults
to using the legacy interface for virtio_mmio. Write the guest page
size register again in virtio_mmio_restore() to make legacy virtio_mmio
devices work correctly after hibernation.
Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Message-Id: <20220621110621.3638025-3-stephan.gerhold@kernkonzept.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Most virtio drivers provide freeze/restore callbacks to finish up
device usage before suspend and to reinitialize the virtio device after
resume. However, these callbacks are currently only called when using
virtio_pci. virtio_mmio does not have any PM ops defined.
This causes problems for example after suspend to disk (hibernation),
since the virtio devices might lose their state after the VMM is
restarted. Calling virtio_device_freeze()/restore() ensures that
the virtio devices are re-initialized correctly.
Fix this by implementing the dev_pm_ops for virtio_mmio,
similar to virtio_pci_common.
Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Message-Id: <20220621110621.3638025-2-stephan.gerhold@kernkonzept.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We try to harden virtio device notifications in 8b4ec69d7e ("virtio:
harden vring IRQ"). It works with the assumption that the driver or
core can properly call virtio_device_ready() at the right
place. Unfortunately, this seems to be not true and uncover various
bugs of the existing drivers, mainly the issue of using
virtio_device_ready() incorrectly.
So let's add a Kconfig option and disable it by default. It gives
us time to fix the drivers and then we can consider re-enabling it.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220622012940.21441-1-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
In function vp_modern_probe(), "pci_dev" is initialized with the
value of "mdev->pci_dev", so assigning "pci_dev" to "mdev->pci_dev"
is unnecessary since they store the same value.
Signed-off-by: Bo Liu <liubo03@inspur.com>
Message-Id: <20220617055952.5364-1-liubo03@inspur.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
the used_wrap_counter and the vq->last_used_idx may get
out of sync if they are separate assignment，and interrupt
might use an incorrect value to check for the used index.
for example:OOB access
ksoftirqd may consume the packet and it will call:
virtnet_poll
-->virtnet_receive
-->virtqueue_get_buf_ctx
-->virtqueue_get_buf_ctx_packed
and in virtqueue_get_buf_ctx_packed:
vq->last_used_idx += vq->packed.desc_state[id].num;
if (unlikely(vq->last_used_idx >= vq->packed.vring.num)) {
vq->last_used_idx -= vq->packed.vring.num;
vq->packed.used_wrap_counter ^= 1;
}
if at the same time, there comes a vring interrupt，in vring_interrupt:
we will call:
vring_interrupt
-->more_used
-->more_used_packed
-->is_used_desc_packed
in is_used_desc_packed, the last_used_idx maybe >= vq->packed.vring.num.
so this could case a memory out of bounds bug.
this patch is to keep the used_wrap_counter in vq->last_used_idx
so we can get the correct value to check for used index in interrupt.
v3->v4:
- use READ_ONCE/WRITE_ONCE to get/set vq->last_used_idx
v2->v3:
- add inline function to get used_wrap_counter and last_used
- when use vq->last_used_idx, only read once
if vq->last_used_idx is read twice, the values can be inconsistent.
- use last_used_idx & ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))
to get the all bits below VRING_PACKED_EVENT_F_WRAP_CTR
v1->v2:
- reuse the VRING_PACKED_EVENT_F_WRAP_CTR
- Remove parameter judgment in is_used_desc_packed,
because it can't be illegal
Signed-off-by: huangjie.albert <huangjie.albert@bytedance.com>
Message-Id: <20220617020411.80367-1-huangjie.albert@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Pull virtio fixes from Michael Tsirkin:
"Fixes all over the place, most notably fixes for latent bugs in
drivers that got exposed by suppressing interrupts before DRIVER_OK,
which in turn has been done by 8b4ec69d7e ("virtio: harden vring
IRQ")"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
um: virt-pci: set device ready in probe()
vdpa: make get_vq_group and set_group_asid optional
virtio: Fix all occurences of the "the the" typo
vduse: Fix NULL pointer dereference on sysfs access
vringh: Fix loop descriptors check in the indirect cases
vdpa/mlx5: clean up indenting in handle_ctrl_vlan()
vdpa/mlx5: fix error code for deleting vlan
virtio-mmio: fix missing put_device() when vm_cmdline_parent registration failed
vdpa/mlx5: Fix syntax errors in comments
virtio-rng: make device ready before making request
Instead of using arch_has_restricted_virtio_memory_access() together
with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those
with platform_has() and a new platform feature
PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 only
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Borislav Petkov <bp@suse.de>
This is a rework on the previous IRQ hardening that is done for
virtio-pci where several drawbacks were found and were reverted:
1) try to use IRQF_NO_AUTOEN which is not friendly to affinity managed IRQ
that is used by some device such as virtio-blk
2) done only for PCI transport
The vq->broken is re-used in this patch for implementing the IRQ
hardening. The vq->broken is set to true during both initialization
and reset. And the vq->broken is set to false in
virtio_device_ready(). Then vring_interrupt() can check and return
when vq->broken is true. And in this case, switch to return IRQ_NONE
to let the interrupt core aware of such invalid interrupt to prevent
IRQ storm.
The reason of using a per queue variable instead of a per device one
is that we may need it for per queue reset hardening in the future.
Note that the hardening is only done for vring interrupt since the
config interrupt hardening is already done in commit 22b7050a02
("virtio: defer config changed notifications"). But the method that is
used by config interrupt can't be reused by the vring interrupt
handler because it uses spinlock to do the synchronization which is
expensive.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-9-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
This patch addresses the checkpatch.pl warning that long long is
preferred over long long int.
Signed-off-by: Solomon Tan <solomonbstoner@protonmail.ch>
Message-Id: <YlzTUQa06sP94zxB@ArchDesktop>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch addresses the checkpatch.pl warning where unsigned int is
preferred over unsigned.
Signed-off-by: Solomon Tan <solomonbstoner@protonmail.ch>
Message-Id: <YlzS49Wo8JMDhKOt@ArchDesktop>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
GCC 12 enhanced -Waddress when comparing array address to null [0],
which warns:
drivers/virtio/virtio_pci_common.c: In function ‘vp_del_vqs’:
drivers/virtio/virtio_pci_common.c:257:29: warning: the comparison will always evaluate as ‘true’ for the pointer operand in ‘vp_dev->msix_affinity_masks + (sizetype)((long unsigned int)i * 256)’ must not be NULL [-Waddress]
257 | if (vp_dev->msix_affinity_masks[i])
| ^~~~~~
In fact, the verification is comparing the result of a pointer
arithmetic, the address "msix_affinity_masks + i", which will always
evaluate to true.
Under the hood, free_cpumask_var() calls kfree(), which is safe to pass
NULL, not requiring non-null verification. So remove the verification
to make compiler happy (happy compiler, happy life).
[0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102103
Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Message-Id: <20220415023002.49805-1-muriloo@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Christophe de Dinechin <dinechin@redhat.com>
