On Dec 14, 2007 11:44 PM, Alan Stern <[EMAIL PROTECTED]> wrote: > On Fri, 14 Dec 2007, Dave Young wrote: > > > Hi, > > The behaviour of my mp3 player (also act as usb-storage device) seems > > changed from rc5 to rc5-mm1. > > This can't be considered a bug, right?
I'm not sure. > It's just that the player > changed from one slightly non-standard behavior to a different slightly > non-standard behavior. > > > > <dmesg output under rc5>: > > ========= > > usb 1-7: new high speed USB device using ehci_hcd and address 7 > > usb 1-7: configuration #1 chosen from 1 choice > > scsi4 : SCSI emulation for USB Mass Storage devices > > usb-storage: device found at 7 > > usb-storage: waiting for device to settle before scanning > > scsi 4:0:0:0: Direct-Access Newman mp3 PQ: 0 ANSI: > > 0 CCS > > sd 4:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 4:0:0:0: [sdb] Write Protect is on > > sd 4:0:0:0: [sdb] Mode Sense: 03 00 80 00 > > sd 4:0:0:0: [sdb] Assuming drive cache: write through > > sd 4:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 4:0:0:0: [sdb] Write Protect is on > > sd 4:0:0:0: [sdb] Mode Sense: 03 00 80 00 > > sd 4:0:0:0: [sdb] Assuming drive cache: write through > > sdb: sdb1 > > sd 4:0:0:0: [sdb] Attached SCSI removable disk > > sd 4:0:0:0: Attached scsi generic sg1 type 0 > > usb-storage: device scan complete > > > > ========== > > try mount it (or just blockdev --rereadpt), then write protect become off: > > ========== > > > > sd 4:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 4:0:0:0: [sdb] Write Protect is off > > sd 4:0:0:0: [sdb] Mode Sense: 03 00 00 00 > > sd 4:0:0:0: [sdb] Assuming drive cache: write through > > sd 4:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 4:0:0:0: [sdb] Write Protect is off > > sd 4:0:0:0: [sdb] Mode Sense: 03 00 00 00 > > sd 4:0:0:0: [sdb] Assuming drive cache: write through > > sdb: sdb1 > > This output won't appear if you simply mount the device. So how do you > know that mounting turns off write protect? This can be observed by eye: dmesg -> mount -> dmesg > > > But under rc5-mm1, after mount command being executed, it is just > > mouted as read only partition without set the write-protect to off > > > > I tried "blockdev --rereadpt", it do set the write-protect to off as rc5 > > kernel. > > > > Below is the output of dmesg under rc5-mm1 > > ========== > > usb 1-8: new high speed USB device using ehci_hcd and address 6 > > usb 1-8: configuration #1 chosen from 1 choice > > scsi3 : SCSI emulation for USB Mass Storage devices > > usb-storage: device found at 6 > > usb-storage: waiting for device to settle before scanning > > scsi 3:0:0:0: Direct-Access Newman mp3 PQ: 0 ANSI: > > 0 CCS > > sd 3:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 3:0:0:0: [sdb] Write Protect is on > > sd 3:0:0:0: [sdb] Mode Sense: 03 00 80 00 > > sd 3:0:0:0: [sdb] Assuming drive cache: write through > > sd 3:0:0:0: [sdb] 245248 512-byte hardware sectors (126 MB) > > sd 3:0:0:0: [sdb] Write Protect is on > > sd 3:0:0:0: [sdb] Mode Sense: 03 00 80 00 > > sd 3:0:0:0: [sdb] Assuming drive cache: write through > > sdb: sdb1 > > This looks exactly the same as the output above (except for various > port, device, and bus numbers). Yes, but lacks the part of "'Write Protect if off' and other lines". > > If you turn on CONFIG_USB_STORAGE_DEBUG for both kernels and compare > the dmesg output for the mount command, that might highlight the > difference. Ok, I will test with do once have time, thanks. Regards dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
