On Tue, May 16, 2023 at 11:12:44AM +0800, Zhangfei Gao wrote: > > > However when debugging hotplug PCI device, it still does not work, > > > Segmentation fault same as 6.2. > > > > > > guest kernel > > > CONFIG_HOTPLUG_PCI_PCIE=y > > > > > > boot guest (this info does not appear in 6.2) > > > qemu-system-aarch64: -device > > > vfio-pci,host=0000:76:00.1,bus=pci.1,addr=0x0,id=acc1,iommufd=iommufd0: > > > Failed to set data -1 > > > qemu-system-aarch64: -device > > > vfio-pci,host=0000:76:00.1,bus=pci.1,addr=0x0,id=acc1,iommufd=iommufd0: > > > failed to set device data > > > > Hmm.. I wonder what fails the set_dev_data ioctl... > Simply debug, it is because dev_data.sid=0, causing > arm_smmu_set_dev_user_data fail I found that too. The input pci bus number is 1, yet the in the context of set_dev_data, the pci bus number is 0, which resulted in a 0-valued sid. I will take another look to get why. > > > $ sudo nc -U /tmp/qmpm_1.socket > > > (qemu) info pci > > > (qemu) device_del acc1 > > > > > > guest: > > > qemu-system-aarch64: IOMMU_IOAS_UNMAP failed: No such file or directory > > > qemu-system-aarch64: vfio_container_dma_unmap(0xaaaae1fc0380, > > > 0x8000000000, 0x10000) = -2 (No such file or directory) > > > From ex-email reply > (Eric) In qemu arm virt machine 0x8000000000 matches the PCI MMIO region. > (Yi) Currently, iommufd kernel part doesn't support mapping device BAR MMIO. > This is a known gap. OK. > > > qemu-system-aarch64: Failed to unset data -1 > > > Segmentation fault (core dumped). // also happened in 6.2 > > > > Hmm, would it be possible for you to run the test again by > > adding the following tracers to your QEMU command? > > --trace "iommufd*" \ > > --trace "smmu*" \ > > --trace "vfio_*" \ > > --trace "pci_*" > > > > Have sent you the log directly, since it is too big. I have found two missing pieces in the device detach routine. Applying the following should fix the crash at hotplug path. ---------------------------------------------------------------------------- diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c index 89a256efa999..2344307523cb 100644 --- a/hw/vfio/container-base.c +++ b/hw/vfio/container-base.c @@ -151,8 +151,10 @@ void vfio_container_destroy(VFIOContainer *container) } QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) { - memory_region_unregister_iommu_notifier( - MEMORY_REGION(giommu->iommu_mr), &giommu->n); + if (giommu->n.notifier_flags) { + memory_region_unregister_iommu_notifier( + MEMORY_REGION(giommu->iommu_mr), &giommu->n); + } QLIST_REMOVE(giommu, giommu_next); g_free(giommu); } diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c index 844c60892db2..35d31480390d 100644 --- a/hw/vfio/iommufd.c +++ b/hw/vfio/iommufd.c @@ -652,6 +652,9 @@ found: */ if (QLIST_EMPTY(&container->hwpt_list)) { vfio_as_del_container(space, bcontainer); + if (bcontainer->nested) { + memory_listener_unregister(& bcontainer->prereg_listener); + } } __vfio_device_detach_container(vbasedev, container, &err); if (err) { ---------------------------------------------------------------------------- Would you please try your case with it? Thanks Nic