similar to: [PATCH 3/3] vhost: make default mapping empty by default

On biarch kernels, it is not safe to do copy from/to user, even with use_mm, unless we checked the address range with access_ok previously. Implement these checks to enforce safe memory accesses. Reported-by: Al Viro <viro at zeniv.linux.org.uk> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/net.c | 17 ++++++- drivers/vhost/vhost.c | 111

On biarch kernels, it is not safe to do copy from/to user, even with use_mm, unless we checked the address range with access_ok previously. Implement these checks to enforce safe memory accesses. Reported-by: Al Viro <viro at zeniv.linux.org.uk> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/net.c | 17 ++++++- drivers/vhost/vhost.c | 111

Current pre-sorted memory region array has some limitations for future device IOTLB conversion: 1) need extra work for adding and removing a single region, and it's expected to be slow because of sorting or memory re-allocation. 2) need extra work of removing a large range which may intersect several regions with different size. 3) need trick for a replacement policy like LRU To

On Mon, 18 Jan 2016 10:42:29 +0800 Jason Wang <jasowang at redhat.com> wrote: > Current pre-sorted memory region array has some limitations for future > device IOTLB conversion: > > 1) need extra work for adding and removing a single region, and it's > expected to be slow because of sorting or memory re-allocation. > 2) need extra work of removing a large range

On Fri, Mar 25, 2016 at 10:34:33AM +0800, Jason Wang wrote: > Current pre-sorted memory region array has some limitations for future > device IOTLB conversion: > > 1) need extra work for adding and removing a single region, and it's > expected to be slow because of sorting or memory re-allocation. > 2) need extra work of removing a large range which may intersect >

On Fri, Mar 25, 2016 at 10:34:33AM +0800, Jason Wang wrote: > Current pre-sorted memory region array has some limitations for future > device IOTLB conversion: > > 1) need extra work for adding and removing a single region, and it's > expected to be slow because of sorting or memory re-allocation. > 2) need extra work of removing a large range which may intersect >

Current pre-sorted memory region array has some limitations for future device IOTLB conversion: 1) need extra work for adding and removing a single region, and it's expected to be slow because of sorting or memory re-allocation. 2) need extra work of removing a large range which may intersect several regions with different size. 3) need trick for a replacement policy like LRU To

Current pre-sorted memory region array has some limitations for future device IOTLB conversion: 1) need extra work for adding and removing a single region, and it's expected to be slow because of sorting or memory re-allocation. 2) need extra work of removing a large range which may intersect several regions with different size. 3) need trick for a replacement policy like LRU To

This fixes two issues with recent access checking patch: 1. if (&d->vqs[i].private_data) -> if (d->vqs[i].private_data) 2. we can't forbid log base changes while ring is running, because host needs to resize log in rare cases (e.g. when memory is added with a baloon) and in that case it needs to increase log size with realloc, which might move the log address.

This fixes two issues with recent access checking patch: 1. if (&d->vqs[i].private_data) -> if (d->vqs[i].private_data) 2. we can't forbid log base changes while ring is running, because host needs to resize log in rare cases (e.g. when memory is added with a baloon) and in that case it needs to increase log size with realloc, which might move the log address.

This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation. Signed-off-by: Jason Wang <jasowang at redhat.com> --- MAINTAINERS | 1 + drivers/vhost/Kconfig | 7 ++

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

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) - support memory

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) - support memory

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) - support memory

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) - support memory

On Fri, Mar 25, 2016 at 10:34:34AM +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 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: > >

On Fri, Mar 25, 2016 at 10:34:34AM +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 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: > >

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

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) - support memory