Re: [Linux-usb-users] Failed reads from RAID-0 array (from newbie who has read the FAQ)

[Neil Brown <neilb@suse.de>]

On Sunday March 18, mschwarz@multitool.net wrote:
> cp -rv /mnt/* fs2d2/
> 
> At this point, the process hangs. So I ran:
> 
> echo t > /proc/sysrq-trigger
> dmesg > dmesg-5-hungread.log

Unfortunate (as you say) the whole trace doesn't fit.
Could you try compiling the kernel with a larger value for
CONFIG_LOG_BUF_SHIFT ??  It looks like you have 17.  21 is the max. 
19 should probably be sufficient.

Two things look a bit odd.
1/ hald-addon-st (process 3974) seems to be hung doing a
  'test_unit_ready' after a media-changed signal.  Any idea why?
  Could you try killing of hald while running the test?

2/ one usb-storage thread (3667) appears to be waiting for
  IO to complete (though that is just a guess really).

Maybe usb-storage is waiting for the hald test-unit-ready?

But I'm a bit out of my depth here, so I'll leave it to the USB
experts.

NeilBrown

 =======================
hald-addon-st D EF9FBD00  2812  3974   2935          3977  3966 (NOTLB)
       ef9fbd14 00000086 00000002 ef9fbd00 ef9fbcfc 00000000 00000000 ed4fcbe4 
       c04dc5cc 00000086 0000000a ed407770 c06fb480 18f88700 00000206 00000000 
       ed40787c c1c8c480 00000000 ebe7adc0 001d605d db30e9c8 00000096 ffffffff 
Call Trace:
 [<c04dc5cc>] elv_next_request+0xfe/0x1ac
 [<c061e701>] wait_for_completion+0x73/0x98
 [<c04226ab>] default_wake_function+0x0/0xc
 [<c04df415>] blk_execute_rq+0xcf/0xe5
 [<c04de74f>] blk_end_sync_rq+0x0/0x23
 [<c04dbdf0>] elv_set_request+0x14/0x22
 [<c04decda>] get_request+0x205/0x2b2
 [<c04df4e7>] get_request_wait+0x26/0x16c
 [<f8de1116>] scsi_execute+0xc6/0xd9 [scsi_mod]
 [<f8de11e0>] scsi_execute_req+0xb7/0xd5 [scsi_mod]
 [<f8de1241>] scsi_test_unit_ready+0x43/0x80 [scsi_mod]
 [<f8d726a5>] sd_media_changed+0x60/0xb5 [sd_mod]
 [<c04e8c82>] kobject_get+0xf/0x13
 [<c0491481>] check_disk_change+0x16/0x5c
 [<c055890a>] class_device_get+0xe/0x14
 [<f8d72b70>] sd_open+0x92/0x120 [sd_mod]
 [<c04e14cc>] exact_match+0x0/0x4
 [<c0491b65>] do_open+0x19f/0x255
 [<c0491d8e>] blkdev_open+0x0/0x4d
 [<c0491db3>] blkdev_open+0x25/0x4d
 [<c0470cac>] __dentry_open+0xc3/0x17a
 [<c0470ddd>] nameidata_to_filp+0x24/0x33
 [<c0470e1e>] do_filp_open+0x32/0x39
 [<c061f0e0>] do_nanosleep+0x42/0x66
 [<c0470bdf>] get_unused_fd+0xb3/0xbd
 [<c0470e67>] do_sys_open+0x42/0xbe
 [<c0470f1c>] sys_open+0x1c/0x1e
 [<c0403f64>] syscall_call+0x7/0xb
 =======================
usb-storage   S 00000010  3048  3667      7          3669  3666 (L-TLB)
       ebcaee78 00000046 f88459c0 00000010 ebc6b7dc f6de08e4 c0587c0e 00000010 
       00000000 c06fb480 0000000a ed5f2bb0 d80fa9b0 e8b0e880 00000205 00000000 
       ed5f2cbc c1c8c480 00000000 ebe7a9c0 001d5d31 00000205 00000000 ffffffff 
Call Trace:
 [<c0587c0e>] usb_hcd_submit_urb+0x6cd/0x773
 [<c061ecc2>] schedule_timeout+0x13/0x8d
 [<c061e925>] wait_for_completion_interruptible_timeout+0x99/0xd5
 [<c04226ab>] default_wake_function+0x0/0xc
 [<f8db090c>] usb_stor_msg_common+0xc9/0xe8 [usb_storage]
 [<f8db0d5f>] usb_stor_bulk_transfer_buf+0x61/0x98 [usb_storage]
 [<f8db12a9>] usb_stor_Bulk_transport+0xcb/0x221 [usb_storage]
 [<f8db2022>] usb_stor_control_thread+0x0/0x1a3 [usb_storage]
 [<f8db1414>] usb_stor_invoke_transport+0x15/0x259 [usb_storage]
 [<c061fa40>] __down_interruptible+0xde/0xf0
 [<c04226ab>] default_wake_function+0x0/0xc
 [<f8db2022>] usb_stor_control_thread+0x0/0x1a3 [usb_storage]
 [<f8db214a>] usb_stor_control_thread+0x128/0x1a3 [usb_storage]
 [<c0420a03>] complete+0x39/0x48
 [<f8db2022>] usb_stor_control_thread+0x0/0x1a3 [usb_storage]
 [<c043779f>] kthread+0xb0/0xd9
 [<c04376ef>] kthread+0x0/0xd9
 [<c0404b33>] kernel_thread_helper+0x7/0x10
 =======================