similar to: [PATCH] vhost-net: avoid flush under lock

From: Shirley Ma <mashirle at us.ibm.com> This adds experimental zero copy support in vhost-net, disabled by default. To enable, set the zerocopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is monitored

From: Shirley Ma <mashirle at us.ibm.com> This adds experimental zero copy support in vhost-net, disabled by default. To enable, set the zerocopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is monitored

Fix the leaking of oldubufs and fd refcnt when fail to initialized used ring. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/net.c | 14 +++++++++++--- 1 files changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index ebd08b2..629d6b5 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -834,8 +834,10 @@ static

Fix the leaking of oldubufs and fd refcnt when fail to initialized used ring. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/net.c | 14 +++++++++++--- 1 files changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index ebd08b2..629d6b5 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -834,8 +834,10 @@ static

vhost_net_ubuf_put_and_wait has a confusing name: it will actually also free it's argument. Thus since commit 1280c27f8e29acf4af2da914e80ec27c3dbd5c01 vhost_net_flush tries to use the argument after passing it to vhost_net_ubuf_put_and_wait, this results in use after free. To fix, don't free the argument in vhost_net_ubuf_put_and_wait, add an new API for callers that want to free ubufs.

vhost_net_ubuf_put_and_wait has a confusing name: it will actually also free it's argument. Thus since commit 1280c27f8e29acf4af2da914e80ec27c3dbd5c01 vhost_net_flush tries to use the argument after passing it to vhost_net_ubuf_put_and_wait, this results in use after free. To fix, don't free the argument in vhost_net_ubuf_put_and_wait, add an new API for callers that want to free ubufs.

This adds experimental zero copy support in vhost-net, disabled by default. To enable, set the zerocopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is monitored through last reference of kfree_skb callback. Two

This adds experimental zero copy support in vhost-net, disabled by default. To enable, set the zerocopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is monitored through last reference of kfree_skb callback. Two

Hi! Recently I have been investigating some strange migration problems on s390x. It turned out under certain circumstances vhost_net corrupts avail.idx by using wrong endianness. I managed to track the problem down (I'm pretty sure). It boils down to the following. When stopping vhost userspace (QEMU) calls vhost_net_set_backend with the fd argument set to -1, this leads to is_le being

Hi! Recently I have been investigating some strange migration problems on s390x. It turned out under certain circumstances vhost_net corrupts avail.idx by using wrong endianness. I managed to track the problem down (I'm pretty sure). It boils down to the following. When stopping vhost userspace (QEMU) calls vhost_net_set_backend with the fd argument set to -1, this leads to is_le being

On 13.02.20 17:29, Eugenio P?rez wrote: > Can we try with this traces? Does not apply on eccb852f1fe6bede630e2e4f1a121a81e34354ab, can you double check? > > From b793b4106085ab1970bdedb340e49f37843ed585 Mon Sep 17 00:00:00 2001 > From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma at redhat.com> > Date: Thu, 13 Feb 2020 17:27:05 +0100 > Subject: [PATCH] vhost: Add debug in

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

I did ping -c 20 -f ... ; reboot twice The ping after the first reboot showed .......E this was on the host console [ 55.951885] CPU: 34 PID: 1908 Comm: CPU 0/KVM Not tainted 5.5.0+ #21 [ 55.951891] Hardware name: IBM 3906 M04 704 (LPAR) [ 55.951892] Call Trace: [ 55.951902] [<0000001ede114132>] show_stack+0x8a/0xd0 [ 55.951906] [<0000001edeb0672a>]

>From: Shirley Ma <mashirle at us.ibm.com> This adds experimental zero copy support in vhost-net, disabled by default. To enable, set experimental_zcopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is

>From: Shirley Ma <mashirle at us.ibm.com> This adds experimental zero copy support in vhost-net, disabled by default. To enable, set experimental_zcopytx module option to 1. This patch maintains the outstanding userspace buffers in the sequence it is delivered to vhost. The outstanding userspace buffers will be marked as done once the lower device buffers DMA has finished. This is

On 14.02.20 08:40, Eugenio Perez Martin wrote: > Hi. > > Were the vhost and vhost_net modules loaded with dyndbg='+plt'? I miss > all the others regular debug traces on that one. I did echo -n 'file drivers/vhost/vhost.c +plt' > control and echo -n 'file drivers/vhost/net.c +plt' > control but apparently it did not work...me hates dynamic debug.

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds

We don't support changing ring size or log base while ring is running. If user violates these rules, he might get his memory silently corrupted. It's better to be explicit, and fail such modification attempts with an error. To make these "vq running" checks in ioctl context robust, this patch also moves all vq flushes to under device mutex. Signed-off-by: Michael S. Tsirkin