Hello,
On Tue, June 24, 2008 16:41, Alan Stern wrote:
> This is a nasty problem. What happened is that the endpoint pointer
> arrays ep_in and ep_out in struct usb_device get cleared before the
> device drivers' disconnect methods are called. Since usb-storage
> dereferences one of the pointers in those arrays, you ended up with an
> invalid memory access.
>
> In principle the arrays should not be cleared until after the drivers
> have been unbound. However for now it is simpler to remove the
> dereference in usb-storage. Especially since the reason for adding it
> in the first place turned out to be wrong.
>
> Is this oops fairly reproducible? If it is, then you should be able to
> test whether this patch fixes it.
>
> Alan Stern
>
>
>
> Index: usb-2.6/drivers/usb/storage/scsiglue.c
> ===================================================================
> --- usb-2.6.orig/drivers/usb/storage/scsiglue.c
> +++ usb-2.6/drivers/usb/storage/scsiglue.c
> @@ -71,7 +71,6 @@ static const char* host_info(struct Scsi
> static int slave_alloc (struct scsi_device *sdev)
> {
> struct us_data *us = host_to_us(sdev->host);
> - struct usb_host_endpoint *bulk_in_ep;
>
> /*
> * Set the INQUIRY transfer length to 36. We don't use any of
> @@ -80,16 +79,22 @@ static int slave_alloc (struct scsi_devi
> */
> sdev->inquiry_len = 36;
>
> - /* Scatter-gather buffers (all but the last) must have a length
> - * divisible by the bulk maxpacket size. Otherwise a data packet
> - * would end up being short, causing a premature end to the data
> - * transfer. We'll use the maxpacket value of the bulk-IN pipe
> - * to set the SCSI device queue's DMA alignment mask.
> + /* USB has unusual DMA-alignment requirements: Although the
> + * starting address of each scatter-gather element doesn't matter,
> + * the length of each element except the last must be divisible
> + * by the Bulk maxpacket value. There's currently no way to
> + * express this by block-layer constraints, so we'll cop out
> + * and simply require addresses to be aligned at 512-byte
> + * boundaries. This is okay since most block I/O involves
> + * hardware sectors that are multiples of 512 bytes in length,
> + * and since host controllers up through USB 2.0 have maxpacket
> + * values no larger than 512.
> + *
> + * But it doesn't suffice for Wireless USB, where Bulk maxpacket
> + * values can be as large as 2048. To make that work properly
> + * will require changes to the block layer.
> */
> - bulk_in_ep = us->pusb_dev->ep_in[usb_pipeendpoint(us->recv_bulk_pipe)];
> - blk_queue_update_dma_alignment(sdev->request_queue,
> - le16_to_cpu(bulk_in_ep->desc.wMaxPacketSize) - 1);
> - /* wMaxPacketSize must be a power of 2 */
> + blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
>
> /*
> * The UFI spec treates the Peripheral Qualifier bits in an
>
I hit almost the same BUG, so tried out this patch, and can confirm that
it fixes the BUG. Other devices still work too. As it's 2.6.26-rc9 it might
be time to send this patch upstream, before it's too late.
Any idea why my cardreader doesn't work in the first place though?
The error is basically:
usb 1-5: new high speed USB device using ehci_hcd and address 22
usb 1-5: device not accepting address 22, error -71
usb 1-5: new high speed USB device using ehci_hcd and address 23
usb 1-5: configuration #1 chosen from 1 choice
scsi17 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 23
usb-storage: waiting for device to settle before scanning
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: reset high speed USB device using ehci_hcd and address 23
scsi 17:0:0:0: Direct-Access Generic USB SD Reader 1.00 PQ: 0 ANSI: 0
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: device not accepting address 23, error -71
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: reset high speed USB device using ehci_hcd and address 23
usb 1-5: can't restore configuration #1 (error=-71)
usb 1-5: USB disconnect, address 23
sd 17:0:0:0: [sdb] READ CAPACITY failed
sd 17:0:0:0: [sdb] Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK,SUGGEST_OK
sd 17:0:0:0: [sdb] Sense not available.
sd 17:0:0:0: [sdb] Write Protect is off
sd 17:0:0:0: [sdb] Mode Sense: 00 00 00 00
sd 17:0:0:0: [sdb] Assuming drive cache: write through
sd 17:0:0:0: [sdb] Attached SCSI removable disk
sd 17:0:0:0: Attached scsi generic sg2 type 0
usb-storage: device scan complete
usb 1-5: new high speed USB device using ehci_hcd and address 24
usb 1-5: string descriptor 0 read error: -71
usb 1-5: configuration #1 chosen from 1 choice
usb 1-5: can't set config #1, error -71
It's a new Trust Mini Cardreader, model CR-1350p.
$ lsusb -s 24 -v
Bus 001 Device 024: ID 058f:6332 Alcor Micro Corp.
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x058f Alcor Micro Corp.
idProduct 0x6332
bcdDevice 1.02
iManufacturer 1
iProduct 2
iSerial 3
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 32
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 100mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 8 Mass Storage
bInterfaceSubClass 6 SCSI
bInterfaceProtocol 80 Bulk (Zip)
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
It doesn't matter in which port I put the thing (front, back),
and I've tried older kernels too (2.6.12), but I get the same
error there. This is with an Intel 945G chipset.
(I've no Windows to test if it works there.)
Is it just a crappy device which I should bring back, or is
there more going on?
Greetings,
Indan
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