> From: Nicolin Chen <nicolinc@xxxxxxxxxx> > Sent: Thursday, March 16, 2023 7:23 AM > > On Tue, Mar 14, 2023 at 11:38:11AM +0000, Shameerali Kolothum Thodi > wrote: > > > Hi Nicolin, > > > > I rebased your latest Qemu branch[1] on top of v7.2.0 and not observed > > the above issue so far. However noticed couple of other issues when > > we try to hot add/remove devices. > > > > (qemu) device_del net1 > > qemu-system-aarch64-iommufd: Failed to free id: 4 Inappropriate ioctl for > device > > qemu-system-aarch64-iommufd: IOMMU_IOAS_UNMAP failed: No such > file or directory > > qemu-system-aarch64-iommufd: vfio_dma_unmap(0xaaaaf587a3d0, > 0x8000101000, 0xf000) = -2 (No such file or directory) > > qemu-system-aarch64-iommufd: IOMMU_IOAS_UNMAP failed: No such > file or directory > > qemu-system-aarch64-iommufd: vfio_dma_unmap(0xaaaaf587a3d0, > 0x8000000000, 0x100000) = -2 (No such file or directory) > > qemu-system-aarch64-iommufd: Failed to free id:1 Device or resource > busy > > > > Ignoring the MMIO UNMAP errors, it looks like the object free is > > not proper on dev removal path. I have few quick fixes here > > for this, > > https://github.com/hisilicon/qemu/tree/private-v7.2.0-iommufd-nesting > > The smmuv3 change looks good to me. I will let Yi check the > iommufd change. > > Yi, I wonder if this is the hot reset case that you asked me > for, a couple of weeks ago. Aha, not really. What Thodi does is the hot removal which is emulating hot-plug out a physical device from the PCI slot. It may trigger hot reset though since reset is something needs to be done during it. However, it's not a focus test as I asked weeks ago. 😊 Regards, Yi Liu