Most of the time - but not always - I get, when inserting an USB3 stick in an USB3 port, errors like that:
device descriptor read/64, error -71
...
device not accepting address XX, error -71
...
Device not responding to setup address.
The same stick is recognized correctly in an USB2 port
Googling around this could be due to IOMMU settings in BIOS/grub, etc., and this could impact (or impede) running virtual machines, and also incorrect id of USB2 devices. Some Ubuntu forum posts suggest using “iommu=soft” in grub or kernel options.
In this gigabyte GA-A320M-S2H mobo there is an option to set IOMMU to Auto/Disabled/Enabled, apart from enabling the AMD SVM virtualization extensions in a separate BIOS menu.
IOMMU was set to auto in BIOS. I disabled it and both USB2 and 3 devices are correctly recognized, without changing any grub or kernel options.
AND Virtualbox VMs run normally, didn’t seem to have an impact in performance, or at least, in loading times.
So, my questions are:
What are the consequences of disabling IOMMU in BIOS, if any?
and
Is this a good solution to the USB recognition problem?
Thanks,
Hi
Have a look on the joutrnalctl -b output it should be fine. I use it here for qemu virtual machines and device passthrough. Is it an Intel or AMD system?
Hi Malcolm
There are no issues shown after plugging a stick:
# journalctl -b | grep usb
abr 24 15:07:52 bruno-03 kernel: usb 2-3: new SuperSpeed USB device number 3 using xhci_hcd
abr 24 15:07:52 bruno-03 kernel: usb 2-3: New USB device found, idVendor=13fe, idProduct=6300
abr 24 15:07:52 bruno-03 kernel: usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
abr 24 15:07:52 bruno-03 kernel: usb 2-3: Product: USB DISK 3.0
abr 24 15:07:52 bruno-03 kernel: usb 2-3: Manufacturer:
abr 24 15:07:52 bruno-03 kernel: usb 2-3: SerialNumber: 07009C2678AB1703
abr 24 15:07:52 bruno-03 kernel: usb-storage 2-3:1.0: USB Mass Storage device detected
abr 24 15:07:52 bruno-03 kernel: scsi host9: usb-storage 2-3:1.0
abr 24 15:07:52 bruno-03 mtp-probe[4692]: checking bus 2, device 3: "/sys/devices/pci0000:00/0000:00:01.3/0000:01:00.0/usb2/2-3"
Apparently everything is OK, my doubt is if there is any deleterious consequence in disabling IOMMU at BIOS level.
AMD, it is a A320 chipset mobo with ryzen 5 2600 CPU.
You mean you have it enabled in BIOS? And are there any related parameters set in grub or kernel options, like iommu=soft?
Hi
It is enabled in the BIOS and I use intel_iommu=on, since I have an intel cpu.
For the record, this had nothing to do with IOMMU. It was a dodgy front panel USB3 port. Works OK when the stick is connected to one of the motherboard’s back panel USB3 ports.