On Wed, Jan 16, 2013 at 3:52 AM, Tejun Heo <tj@xxxxxxxxxx> wrote: > This avoids the described deadlock because iosched module doesn't use > async and thus wouldn't invoke async_synchronize_full(). This is > hacky and incomplete. It will deadlock if async module loading nests; > however, this works around the known problem case and seems to be the > best of bad options. I confirm it fixes the original problem. Tested-by: Alex Riesen <raa.lkml@xxxxxxxxx> [ 27.594951] hub 1-1:1.0: state 7 ports 6 chg 0000 evt 0004 [ 27.595245] hub 1-1:1.0: port 2, status 0101, change 0001, 12 Mb/s [ 27.698995] hub 1-1:1.0: debounce: port 2: total 100ms stable 100ms status 0x101 [ 27.709977] hub 1-1:1.0: port 2 not reset yet, waiting 10ms [ 27.771888] usb 1-1.2: new high-speed USB device number 3 using ehci-pci [ 27.782871] hub 1-1:1.0: port 2 not reset yet, waiting 10ms [ 27.857503] usb 1-1.2: default language 0x0409 [ 27.858248] usb 1-1.2: udev 3, busnum 1, minor = 2 [ 27.858258] usb 1-1.2: New USB device found, idVendor=0781, idProduct=5408 [ 27.858263] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 27.858267] usb 1-1.2: Product: U3 Titanium [ 27.858271] usb 1-1.2: Manufacturer: SanDisk Corporation [ 27.858275] usb 1-1.2: SerialNumber: 0000187A3A60F1E9 [ 27.858800] usb 1-1.2: usb_probe_device [ 27.858815] usb 1-1.2: configuration #1 chosen from 1 choice [ 27.858940] usb 1-1.2: adding 1-1.2:1.0 (config #1, interface 0) [ 27.859246] usb-storage 1-1.2:1.0: usb_probe_interface [ 27.859258] usb-storage 1-1.2:1.0: usb_probe_interface - got id [ 27.859516] scsi6 : usb-storage 1-1.2:1.0 [ 28.865771] io scheduler deadline registered (default) [ 28.866705] scsi 6:0:0:0: Direct-Access SanDisk U3 Titanium 2.18 PQ: 0 ANSI: 2 [ 28.869483] sd 6:0:0:0: Attached scsi generic sg1 type 0 [ 28.869700] sd 6:0:0:0: [sdb] 4013713 512-byte logical blocks: (2.05 GB/1.91 GiB) [ 28.870197] sd 6:0:0:0: [sdb] Write Protect is off [ 28.870204] sd 6:0:0:0: [sdb] Mode Sense: 03 00 00 00 [ 28.870692] sd 6:0:0:0: [sdb] No Caching mode page present [ 28.870697] sd 6:0:0:0: [sdb] Assuming drive cache: write through [ 28.873565] sd 6:0:0:0: [sdb] No Caching mode page present [ 28.873575] sd 6:0:0:0: [sdb] Assuming drive cache: write through [ 28.883895] sdb: sdb1 [ 28.887775] sd 6:0:0:0: [sdb] No Caching mode page present [ 28.887783] sd 6:0:0:0: [sdb] Assuming drive cache: write through [ 28.887789] sd 6:0:0:0: [sdb] Attached SCSI removable disk The filesystem can be mounted and files can be read. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
