Dear Maintainer, I was trying to format a 4TB usb external drive. Every time I tried, I saw I/O errors and my gnome desktop froze, requiring a complete power-cycle to recover. I finally used ext4 with no problems. Could be hardware but the enclusure and drive are both brand new, and I don't know why one would succeed and the other fail. Some dmesg output: Aug 26 08:58:37 anton sudo[6470]: msoulier : TTY=pts/0 ; PWD=/home/msoulier ; US ER=root ; COMMAND=/usr/sbin/mkfs -t xfs -f /dev/sdc1 Aug 26 08:58:37 anton sudo[6470]: pam_unix(sudo:session): session opened for use r root(uid=0) by (uid=1000) Aug 26 08:58:37 anton kernel: DMAR: DRHD: handling fault status reg 3 Aug 26 08:58:37 anton kernel: xhci_hcd 0000:00:14.0: WARNING: Host System Error Aug 26 08:58:37 anton kernel: DMAR: [DMA Read NO_PASID] Request device [00:14.0] fault addr 0xff58f000 [fault reason 0x06] PTE Read access is not set Aug 26 08:58:39 anton kernel: usb 2-3: device not accepting address 2, error -10 8 Aug 26 08:58:42 anton kernel: usb 2-3: USB disconnect, device number 2 Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#4 uas_eh_abort_handler 0 uas -tag 11 inflight: CMD OUT Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#4 CDB: Write(16) 8a 00 00 00 00 00 e8 e1 34 48 00 00 04 00 00 00 Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#2 uas_eh_abort_handler 0 uas -tag 10 inflight: CMD OUT Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#2 CDB: Write(16) 8a 00 00 00 00 00 e8 e1 30 48 00 00 04 00 00 00 Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#1 uas_eh_abort_handler 0 uas -tag 9 inflight: CMD OUT Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#1 CDB: Write(16) 8a 00 00 00 00 00 e8 e1 2c 48 00 00 04 00 00 00 Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#0 uas_eh_abort_handler 0 uas -tag 8 inflight: CMD OUT Aug 26 08:59:08 anton kernel: sd 2:0:0:0: [sdc] tag#0 CDB: Write(16) 8a 00 00 00 00 00 e8 e1 28 48 00 00 04 00 00 00 Aug 26 08:59:09 anton kernel: scsi host2: uas_eh_device_reset_handler start Aug 26 08:59:09 anton kernel: usb 2-1: device not accepting address 4, error -10 8 Aug 26 08:59:10 anton kernel: usb 2-1: device not accepting address 4, error -10 8 Aug 26 08:59:10 anton kernel: usb 2-1: device not accepting address 4, error -10 8 Aug 26 08:59:11 anton kernel: usb 2-1: device not accepting address 4, error -10 8