similar to: [PATCH] vhost/vsock: add IOTLB API support

On map: only flush when old PTE was valid or invalid PTE may be cached. On unmap: always flush old entry, but skip flush for unaffected IOMMUs. Signed-off-by: Espen Skoglund <espen.skoglund@netronome.com> -- iommu.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) -- diff -r 8187fd8113f9 xen/drivers/passthrough/vtd/iommu.c ---

Hi, I have a guest enabled vIOMMU, but on the guest there are several devices in the same iommu group. Could someone help to check if I missed something? Thank you very much! 1. guest xml: # virsh edit q ... <os> <type arch='x86_64' machine='pc-q35-rhel7.5.0'>hvm</type> <loader readonly='yes' secure='yes'

On Thu, Apr 28, 2016 at 02:37:16PM +0800, Jason Wang wrote: > > > On 04/27/2016 07:45 PM, Michael S. Tsirkin wrote: > > 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. >

On Thu, Apr 28, 2016 at 02:37:16PM +0800, Jason Wang wrote: > > > On 04/27/2016 07:45 PM, Michael S. Tsirkin wrote: > > 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 iommu is enabled by default when xen is booting and later disabled in iommu_setup() when no iommu is present. But under some circumstances iommu code can be called before iommu_setup() is processed. If there is no iommu available xen crashes. This can happen for example when panic(...) is called as introduced with the patch "x86-64: detect processors subject to AMD erratum #121 and

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: > >

On 04/28/2016 10:43 PM, Michael S. Tsirkin wrote: > On Thu, Apr 28, 2016 at 02:37:16PM +0800, Jason Wang wrote: >> >> On 04/27/2016 07:45 PM, Michael S. Tsirkin wrote: >>> 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

On 04/27/2016 07:45 PM, Michael S. Tsirkin wrote: > 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

On Tue, May 24, 2016 at 05:36:22PM +0800, Jason Wang wrote: > This patch tries to implement an device IOTLB for vhost. This could be > used with for co-operation with userspace IOMMU implementation (qemu) > for a secure DMA environment (DMAR) in guest. > > The idea is simple. When vhost meets an IOTLB miss, it will request > the assistance of userspace to do the translation,

This patch tries to implement an device IOTLB for vhost. This could be used with for co-operation with userspace IOMMU implementation (qemu) for a secure DMA environment (DMAR) 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 done through: - when there's a IOTLB miss, it will notify userspace through

This patch tries to implement an device IOTLB for vhost. This could be used with for co-operation with userspace IOMMU implementation (qemu) for a secure DMA environment (DMAR) 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 done through: - when there's a IOTLB miss, it will notify userspace through

DaeRyong Jeong reports a race between vhost_dev_cleanup() and vhost_process_iotlb_msg(): Thread interleaving: CPU0 (vhost_process_iotlb_msg) CPU1 (vhost_dev_cleanup) (In the case of both VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE) ===== ===== vhost_umem_clean(dev->iotlb); if (!dev->iotlb) { ret = -EFAULT; break; } dev->iotlb = NULL; The reason is

On 2015/12/31 15:13, 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 done > through:

Vq log_base is the userspace address of bitmap which has nothing to do with IOTLB. So it needs to be validated unconditionally otherwise we may try use 0 as log_base which may lead to pin pages that will lead unexpected result (e.g trigger BUG_ON() in set_bit_to_user()). Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API") Reported-by: syzbot+6304bf97ef436580fede at

Vq log_base is the userspace address of bitmap which has nothing to do with IOTLB. So it needs to be validated unconditionally otherwise we may try use 0 as log_base which may lead to pin pages that will lead unexpected result (e.g trigger BUG_ON() in set_bit_to_user()). Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API") Reported-by: syzbot+6304bf97ef436580fede at

On 2016/1/4 14:22, Jason Wang wrote: > > > On 01/04/2016 09:39 AM, Yang Zhang wrote: >> On 2015/12/31 15:13, 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

On 2016/1/4 14:22, Jason Wang wrote: > > > On 01/04/2016 09:39 AM, Yang Zhang wrote: >> On 2015/12/31 15:13, 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

vringh can now be built without IOTLB. Select IOTLB directly where it's used. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Applies on top of my vhost tree. Changes from v1: VDPA_SIM needs VHOST_IOTLB drivers/vdpa/Kconfig | 1 + drivers/vhost/Kconfig | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index

vringh can now be built without IOTLB. Select IOTLB directly where it's used. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Applies on top of my vhost tree. Changes from v1: VDPA_SIM needs VHOST_IOTLB drivers/vdpa/Kconfig | 1 + drivers/vhost/Kconfig | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index