https://bugzilla.kernel.org/show_bug.cgi?id=196527 Bug ID: 196527 Summary: Terrible KVM USB passthrough performance Product: Virtualization Version: unspecified Kernel Version: 4.9.32 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: nazar@xxxxxxxxxxxxxx Regression: No Host system is Alpine Linux x86_64 with kernel 4.9.32 and QEMU 2.8.1-r1. KVM guest is LEDE with Wi-Fi adapter attached to it, chipset used is pc-q35-2.8. Wi-Fi adapter is USB 2.0, but inserted into USB 3.0 port on the motherboard. CPU is Intel Celeron N3150. The problem I'm having is that it can barely cross 30Mbps speed with this Wi-Fi adapter, while both adapter acting as an AP and client device can handle up to 300Mbps, well within USB 2.0 spec and well above what I'm currently seeing. When USB 2.0 was used in VM download speed was only 10Mpbs, when switched to USB 3.0 it increased to 14Mbps, upload in both cases is 30-32Mbps. There is some serious bottleneck, is this an expected level of performance or am I missing something? -- You are receiving this mail because: You are watching the assignee of the bug.
