search for: vq_callback

...(the_virtio_vsock, NULL); >> >> This is still suspicious, can we access the_virtio_vsock through vdev->priv? >> If yes, we may still get use-after-free since it was not protected by RCU. > We will free the object only after calling the del_vqs(), so we are sure > that the vq_callbacks ended and will no longer be invoked. > So, IIUC it shouldn't happen. Yes, but any dereference that is not done in vq_callbacks will be very dangerous in the future. Thanks > >> Another more interesting question, I believe we will do singleton for >> virtio_vsock structu...

...(the_virtio_vsock, NULL); >> >> This is still suspicious, can we access the_virtio_vsock through vdev->priv? >> If yes, we may still get use-after-free since it was not protected by RCU. > We will free the object only after calling the del_vqs(), so we are sure > that the vq_callbacks ended and will no longer be invoked. > So, IIUC it shouldn't happen. Yes, but any dereference that is not done in vq_callbacks will be very dangerous in the future. Thanks > >> Another more interesting question, I believe we will do singleton for >> virtio_vsock structu...

...g, 0, vring_legacy_size(num, 4096)); > vring_legacy_init(&info->vring, num, info->ring, 4096); > - info->vq = vring_new_virtqueue(info->idx, > - info->vring.num, 4096, &dev->vdev, > - true, false, info->ring, > - vq_notify, vq_callback, "test"); > + info->vq = > + __vring_new_virtqueue(info->idx, info->vring, &dev->vdev, true, > + false, vq_notify, vq_callback, "test"); > assert(info->vq); > info->vq->priv = info; > vhost_vq_setup(dev, info); > --...

...; > > > > > This is still suspicious, can we access the_virtio_vsock through vdev->priv? > > > If yes, we may still get use-after-free since it was not protected by RCU. > > We will free the object only after calling the del_vqs(), so we are sure > > that the vq_callbacks ended and will no longer be invoked. > > So, IIUC it shouldn't happen. > > > Yes, but any dereference that is not done in vq_callbacks will be very > dangerous in the future. Right. Do you think make sense to continue with this series in order to fix the hot-unplug issue,...

On 2019/6/28 ??8:36, Stefano Garzarella wrote: > Some callbacks used by the upper layers can run while we are in the > .remove(). A potential use-after-free can happen, because we free > the_virtio_vsock without knowing if the callbacks are over or not. > > To solve this issue we move the assignment of the_virtio_vsock at the > end of .probe(), when we finished all the

On 2019/6/28 ??8:36, Stefano Garzarella wrote: > Some callbacks used by the upper layers can run while we are in the > .remove(). A potential use-after-free can happen, because we free > the_virtio_vsock without knowing if the callbacks are over or not. > > To solve this issue we move the assignment of the_virtio_vsock at the > end of .probe(), when we finished all the

...add(struct vdev_info *dev, int num) vring_init(&info->vring, num, info->ring, 4096); info->vq = vring_new_virtqueue(info->idx, info->vring.num, 4096, &dev->vdev, - true, info->ring, + true, false, info->ring, vq_notify, vq_callback, "test"); assert(info->vq); info->vq->priv = info; diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c index 5f94f5105678..9476c616d064 100644 --- a/tools/virtio/vringh_test.c +++ b/tools/virtio/vringh_test.c @@ -314,7 +314,8 @@ static int parallel_test(u64 f...

...add(struct vdev_info *dev, int num) vring_init(&info->vring, num, info->ring, 4096); info->vq = vring_new_virtqueue(info->idx, info->vring.num, 4096, &dev->vdev, - true, info->ring, + true, false, info->ring, vq_notify, vq_callback, "test"); assert(info->vq); info->vq->priv = info; diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c index 5f94f5105678..9476c616d064 100644 --- a/tools/virtio/vringh_test.c +++ b/tools/virtio/vringh_test.c @@ -314,7 +314,8 @@ static int parallel_test(u64 f...

...assign_pointer(the_virtio_vsock, NULL); > > > This is still suspicious, can we access the_virtio_vsock through vdev->priv? > If yes, we may still get use-after-free since it was not protected by RCU. We will free the object only after calling the del_vqs(), so we are sure that the vq_callbacks ended and will no longer be invoked. So, IIUC it shouldn't happen. > > Another more interesting question, I believe we will do singleton for > virtio_vsock structure. Then what's the point of using vdev->priv to access > the_virtio_vsock? It looks to me we can it brings ex...

Hello, Here are two patches. One implements a virtio-serial device in qemu and the other is the driver for a guest kernel. While working on a vmchannel interface that is needed for communication between guest userspace and host userspace, I saw that most of the interface can be abstracted out as a "serial" device with "ports". Some requirements for a vmchannel are listed at

Hello, Here are two patches. One implements a virtio-serial device in qemu and the other is the driver for a guest kernel. While working on a vmchannel interface that is needed for communication between guest userspace and host userspace, I saw that most of the interface can be abstracted out as a "serial" device with "ports". Some requirements for a vmchannel are listed at

...continue; + ret = virtserial_add_port(port_nr); + if (!ret) + virtserial.config->nr_active_ports++; + } + kfree(virtserconf); +} + +static int virtserial_probe(struct virtio_device *vdev) +{ + struct virtqueue *vqs[2]; + const char *vq_names[] = { "input", "output" }; + vq_callback_t *vq_callbacks[] = { rx_intr, tx_intr }; + u32 i, map; + int ret, map_i; + u32 max_nr_ports; + + vdev->config->get(vdev, offsetof(struct virtio_serial_config, + max_nr_ports), + &max_nr_ports, + sizeof(max_nr_ports)); + virtserial.config = kmalloc(sizeof(struct virtio_serial...

...continue; + ret = virtserial_add_port(port_nr); + if (!ret) + virtserial.config->nr_active_ports++; + } + kfree(virtserconf); +} + +static int virtserial_probe(struct virtio_device *vdev) +{ + struct virtqueue *vqs[2]; + const char *vq_names[] = { "input", "output" }; + vq_callback_t *vq_callbacks[] = { rx_intr, tx_intr }; + u32 i, map; + int ret, map_i; + u32 max_nr_ports; + + vdev->config->get(vdev, offsetof(struct virtio_serial_config, + max_nr_ports), + &max_nr_ports, + sizeof(max_nr_ports)); + virtserial.config = kmalloc(sizeof(struct virtio_serial...

Hello, This is a new iteration of the patches that implement virtio-serial. Changes include: * Adding support for port hot-add * Creating ports at specific ids that can be bound to specific apps / usage * Cleanups This code still doesn't get rid of the support for assigning names to ports but it just has to be ripped out. Comments welcome. Thanks, Amit.

Hello, This is a new iteration of the patches that implement virtio-serial. Changes include: * Adding support for port hot-add * Creating ports at specific ids that can be bound to specific apps / usage * Cleanups This code still doesn't get rid of the support for assigning names to ports but it just has to be ripped out. Comments welcome. Thanks, Amit.

Here's a patchset to update tools/virtio with changes in 3.8, as well as the proposed API extension. Useful to see whether the extra level of indirection adds measureable overhead. I will upstream at least patch 1 soon. Michael S. Tsirkin (2): tools/virtio: fix build for 3.8 tools/virtio: update for the new virtio API drivers/vhost/test.c | 4 +++- tools/virtio/Makefile

Here's a patchset to update tools/virtio with changes in 3.8, as well as the proposed API extension. Useful to see whether the extra level of indirection adds measureable overhead. I will upstream at least patch 1 soon. Michael S. Tsirkin (2): tools/virtio: fix build for 3.8 tools/virtio: update for the new virtio API drivers/vhost/test.c | 4 +++- tools/virtio/Makefile

...struct vdev_info { struct vhost_memory *mem; }; -void vq_notify(struct virtqueue *vq) +int vq_notify(struct virtqueue *vq) { struct vq_info *info = vq->priv; unsigned long long v = 1; int r; r = write(info->kick, &v, sizeof v); assert(r == sizeof v); + return 0; } void vq_callback(struct virtqueue *vq) diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c index d053ea4..965ccfe 100644 --- a/tools/virtio/vringh_test.c +++ b/tools/virtio/vringh_test.c @@ -22,7 +22,7 @@ static u64 user_addr_offset; #define RINGSIZE 256 #define ALIGN 4096 -static void never_no...

Recent changes to drivers/virtio broke compilation for the tests in tools/virtio. The following patches are build fixes for those changes, as well as a fix for a typo that would have never built. The changes were tested on my amd64 system against 3.14-rc2. Joel Stanley (3): tools/virtio: update internal copies of headers tools/virtio: fix missing kmemleak_ignore symbol tools/virtio: add a

Recent changes to drivers/virtio broke compilation for the tests in tools/virtio. The following patches are build fixes for those changes, as well as a fix for a typo that would have never built. The changes were tested on my amd64 system against 3.14-rc2. Joel Stanley (3): tools/virtio: update internal copies of headers tools/virtio: fix missing kmemleak_ignore symbol tools/virtio: add a