similar to: [PATCH v2] vhost: fix IOTLB locking

Commit 78139c94dc8c ("net: vhost: lock the vqs one by one") moved the vq lock to improve scalability, but introduced a possible deadlock in vhost-iotlb. vhost_iotlb_notify_vq() now takes vq->mutex while holding the device's IOTLB spinlock. And on the vhost_iotlb_miss() path, the spinlock is taken while holding vq->mutex. As long as we hold dev->mutex to prevent an ioctl

Commit 78139c94dc8c ("net: vhost: lock the vqs one by one") moved the vq lock to improve scalability, but introduced a possible deadlock in vhost-iotlb. vhost_iotlb_notify_vq() now takes vq->mutex while holding the device's IOTLB spinlock. And on the vhost_iotlb_miss() path, the spinlock is taken while holding vq->mutex. As long as we hold dev->mutex to prevent an ioctl

On Fri, Nov 30, 2018 at 11:37:02AM +0000, Jean-Philippe Brucker wrote: > Commit 78139c94dc8c ("net: vhost: lock the vqs one by one") moved the vq > lock to improve scalability, but introduced a possible deadlock in > vhost-iotlb. vhost_iotlb_notify_vq() now takes vq->mutex while holding > the device's IOTLB spinlock. Indeed spin_lock is just outside this snippet.

Hi, On 25/09/2018 13:36, xiangxia.m.yue at gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue at gmail.com> > > This patch changes the way that lock all vqs > at the same, to lock them one by one. It will > be used for next patch to avoid the deadlock. > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> > Acked-by: Jason Wang <jasowang at

Hi, On 25/09/2018 13:36, xiangxia.m.yue at gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue at gmail.com> > > This patch changes the way that lock all vqs > at the same, to lock them one by one. It will > be used for next patch to avoid the deadlock. > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> > Acked-by: Jason Wang <jasowang at

On 2018/11/30 ??3:28, Jean-Philippe Brucker wrote: > Hi, > > On 25/09/2018 13:36,xiangxia.m.yue at gmail.com wrote: >> From: Tonghao Zhang<xiangxia.m.yue at gmail.com> >> >> This patch changes the way that lock all vqs >> at the same, to lock them one by one. It will >> be used for next patch to avoid the deadlock. >> >> Signed-off-by:

On Sat, Jul 21, 2018 at 11:03:59AM -0700, xiangxia.m.yue at gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue at gmail.com> > > This patch changes the way that lock all vqs > at the same, to lock them one by one. It will > be used for next patch to avoid the deadlock. > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> > Acked-by: Jason Wang

On Sat, Jul 21, 2018 at 11:03:59AM -0700, xiangxia.m.yue at gmail.com wrote: > From: Tonghao Zhang <xiangxia.m.yue at gmail.com> > > This patch changes the way that lock all vqs > at the same, to lock them one by one. It will > be used for next patch to avoid the deadlock. > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> > Acked-by: Jason Wang

This patch tries to implement an device IOTLB for vhost. This could be used with for co-operation with userspace(qemu) implementation of DMA remapping. The idea is simple, cache the translation in a software device IOTLB (which was implemented as interval tree) in vhost and use vhost_net file descriptor for reporting IOTLB miss and IOTLB update/invalidation. When vhost meets an IOTLB miss, the

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patch changes the way that lock all vqs at the same, to lock them one by one. It will be used for next patch to avoid the deadlock. Signed-off-by: Tonghao Zhang <zhangtonghao at didichuxing.com> --- drivers/vhost/vhost.c | 24 +++++++----------------- 1 file changed, 7 insertions(+), 17 deletions(-) diff --git

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patch changes the way that lock all vqs at the same, to lock them one by one. It will be used for next patch to avoid the deadlock. Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> Acked-by: Jason Wang <jasowang at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 24

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patch changes the way that lock all vqs at the same, to lock them one by one. It will be used for next patch to avoid the deadlock. Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> Acked-by: Jason Wang <jasowang at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 24

On Sun, Jul 22, 2018 at 11:26 PM Michael S. Tsirkin <mst at redhat.com> wrote: > > On Sat, Jul 21, 2018 at 11:03:59AM -0700, xiangxia.m.yue at gmail.com wrote: > > From: Tonghao Zhang <xiangxia.m.yue at gmail.com> > > > > This patch changes the way that lock all vqs > > at the same, to lock them one by one. It will > > be used for next patch to avoid

tree: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git vhost head: 51ce50c54895044f949129e595ed9a37e4d6c13a commit: 51ce50c54895044f949129e595ed9a37e4d6c13a [14/14] vhost: new device IOTLB API config: sparc64-allmodconfig (attached as .config) compiler: sparc64-linux-gnu-gcc (Debian 5.4.0-6) 5.4.0 20160609 reproduce: wget

tree: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git vhost head: 51ce50c54895044f949129e595ed9a37e4d6c13a commit: 51ce50c54895044f949129e595ed9a37e4d6c13a [14/14] vhost: new device IOTLB API config: sparc64-allmodconfig (attached as .config) compiler: sparc64-linux-gnu-gcc (Debian 5.4.0-6) 5.4.0 20160609 reproduce: wget

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patch improves the guest receive performance from host. On the handle_tx side, we poll the sock receive queue at the same time. handle_rx do that in the same way. For avoiding deadlock, change the code to lock the vq one by one and use the VHOST_NET_VQ_XX as a subclass for mutex_lock_nested. With the patch, qemu can set differently the

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patch improves the guest receive performance from host. On the handle_tx side, we poll the sock receive queue at the same time. handle_rx do that in the same way. For avoiding deadlock, change the code to lock the vq one by one and use the VHOST_NET_VQ_XX as a subclass for mutex_lock_nested. With the patch, qemu can set differently the

On Thu, Dec 31, 2015 at 03:13:45PM +0800, Jason Wang wrote: > This patch tries to implement an device IOTLB for vhost. This could be > used with for co-operation with userspace(qemu) implementation of > iommu for a secure DMA environment in guest. > > The idea is simple. When vhost meets an IOTLB miss, it will request > the assistance of userspace to do the translation, this is

This patch tries to implement an device IOTLB for vhost. This could be used with for co-operation with userspace(qemu) implementation of DMA remapping. The idea is simple. When vhost meets an IOTLB miss, it will request the assistance of userspace to do the translation, this is done through: - Fill the translation request in a preset userspace address (This address is set through ioctl

From: Tonghao Zhang <xiangxia.m.yue at gmail.com> This patches improve the guest receive performance. On the handle_tx side, we poll the sock receive queue at the same time. handle_rx do that in the same way. For more performance report, see patch 4 Tonghao Zhang (4): net: vhost: lock the vqs one by one net: vhost: replace magic number of lock annotation net: vhost: factor out busy