diff options
| author |   Jason Wang <jasowang@redhat.com> | 2022-06-22 09:29:40 +0800 |
|---|---|---|
| committer |   Michael S. Tsirkin <mst@redhat.com> | 2022-06-24 02:49:48 -0400 |
| commit | c346dae4f3fbce51bbd4f2ec5e8c6f9b91e93163 (patch) | |
| tree | 4e3a09595a5ec554cf002679c587049c627fba49 /drivers/s390 | |
| parent | virtio: Remove unnecessary variable assignments (diff) | |
| download | linux-dev-c346dae4f3fbce51bbd4f2ec5e8c6f9b91e93163.tar.xz linux-dev-c346dae4f3fbce51bbd4f2ec5e8c6f9b91e93163.zip | |
virtio: disable notification hardening by default
We try to harden virtio device notifications in 8b4ec69d7e09 ("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>
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/virtio/virtio_ccw.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c index 97e51c34e6cf..161d3b141f0d 100644 --- a/drivers/s390/virtio/virtio_ccw.c +++ b/drivers/s390/virtio/virtio_ccw.c @@ -1136,8 +1136,13 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev, vcdev->err = -EIO; } virtio_ccw_check_activity(vcdev, activity); - /* Interrupts are disabled here */ +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + /* + * Paired with virtio_ccw_synchronize_cbs() and interrupts are + * disabled here. + */ read_lock(&vcdev->irq_lock); +#endif for_each_set_bit(i, indicators(vcdev), sizeof(*indicators(vcdev)) * BITS_PER_BYTE) { /* The bit clear must happen before the vring kick. */ @@ -1146,7 +1151,9 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev, vq = virtio_ccw_vq_by_ind(vcdev, i); vring_interrupt(0, vq); } +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION read_unlock(&vcdev->irq_lock); +#endif if (test_bit(0, indicators2(vcdev))) { virtio_config_changed(&vcdev->vdev); clear_bit(0, indicators2(vcdev)); |