Comment 7 for bug 363361

Would like to add that this happens to me as well. I found that sticking a usb HD into a slot will get it going again. The only thing in the logs that was odd was some EXT4 stuff
Jun 5 09:22:28 bj-desktop kernel: [112677.880983] ext4: find_group_flex failed, fallback succeeded dir 130977
Jun 5 09:22:44 bj-desktop kernel: [112693.979505] ext4: find_group_flex failed, fallback succeeded dir 5591
Jun 5 09:25:46 bj-desktop kernel: [112876.171814] ext4: find_group_flex failed, fallback succeeded dir 130977
Jun 5 09:29:51 bj-desktop kernel: [113121.428864] ext4: find_group_flex failed, fallback succeeded dir 4438
Jun 5 09:29:51 bj-desktop kernel: [113121.435315] ext4: find_group_flex failed, fallback succeeded dir 4438
Jun 5 09:29:51 bj-desktop kernel: [113121.437846] ext4: find_group_flex failed, fallback succeeded dir 4438
Jun 5 09:29:52 bj-desktop kernel: [113122.125480] ext4: find_group_flex failed, fallback succeeded dir 4438
Jun 5 09:30:51 bj-desktop kernel: [113180.797784] usb 1-3.2.4: reset full speed USB device using ehci_hcd and address 8