#4476 BLOC Update.: Possible USB problem

[Zarro Boogs per Child]

#4476: Possible USB problem
-----------------------+----------------------------------------------------
  Reporter:  carrano   |       Owner:  wad     
      Type:  defect    |      Status:  reopened
  Priority:  blocker   |   Milestone:  Update.1
 Component:  hardware  |     Version:          
Resolution:            |    Keywords:          
  Verified:  0         |  
-----------------------+----------------------------------------------------

Comment(by dwmw2):

 There are certainly locking issues with the driver. Here's a deadlock, for
 example:

 {{{
 [  930.492067] libertas_work S 00000000  2028  1232      2 (L-TLB)
 [  930.526352]        cd3a5d44 00000046 00000000 00000000 c051767a
 00000001 cd5ca958 00000006
 [  930.536108]        cd00f570 47a37787 000000c2 3b9aca00 cd00f690
 17b065bb 000000c2 00000001
 [  930.573764]        cd5ca000 cae80cdc cd3a5ed0 cd3a5edc d0a6931d
 cd3a5dcc cd3a5da0 c04df346
 [  930.611181] Call Trace:
 [  930.669566]  [<d0a6931d>] libertas_send_specific_ssid_scan+0x167/0x1f5
 [libertas]
 [  930.706080]  [<d0a742db>] assoc_helper_associate+0x353/0x5a2 [libertas]
 [  930.741840]  [<d0a75365>] libertas_association_worker+0xe3b/0x10d3
 [libertas]
 [  930.778442]  [<c041e02c>] run_workqueue+0x93/0x125
 [  930.812675]  [<c041e7e3>] worker_thread+0xb7/0xc4
 [  930.846737]  [<c0420d1e>] kthread+0x39/0x5f
 [  930.880166]  [<c0404017>] kernel_thread_helper+0x7/0x10
 }}}
 {{{
 [  925.808289] khubd         D C92B34F5  2436    49      2 (L-TLB)
 [  925.842365]        c1241dd8 00000046 cc3a0570 c92b34f5 000000cb
 c12ca1f8 00000003 0000000a
 [  925.852132]        cedbb030 cad3d7e8 000000cb 000051e2 cedbb150
 c1241e1c c1241e1c cd5ca950
 [  925.889709]        c1241e18 c1241e1c c1241df4 c1241e00 c0616ec6
 00000001 cedbb030 c040e9ab
 [  925.927534] Call Trace:
 [  925.986802]  [<c0616ec6>] wait_for_completion+0x6c/0x91
 [  926.020926]  [<c041e1a9>] flush_cpu_workqueue+0x4f/0x65
 [  926.054676]  [<c041e1f1>] destroy_workqueue+0x32/0x57
 [  926.087646]  [<d0a5b87f>] libertas_remove_card+0x17b/0x2d0 [libertas]
 [  926.122435]  [<d08a4f0e>] 0xd08a4f0e
 [  926.154131]  [<c0545a13>] usb_unbind_interface+0x30/0x72
 [  926.187898]  [<c051ab86>] __device_release_driver+0x74/0x90
 [  926.221915]  [<c051af6b>] device_release_driver+0x2f/0x45
 [  926.255709]  [<c051a51a>] bus_remove_device+0x61/0x6f
 [  926.288592]  [<c0518ead>] device_del+0x1d6/0x24c
 [  926.320722]  [<c05436e6>] usb_disable_device+0x5f/0xbc
 [  926.353103]  [<c05401b3>] usb_disconnect+0x94/0xf0
 [  926.384443]  [<c05407e0>] hub_thread+0x2ec/0x996
 [  926.415421]  [<c0420d1e>] kthread+0x39/0x5f
 [  926.445919]  [<c0404017>] kernel_thread_helper+0x7/0x10
 }}}

 This causes all USB operations to block.

-- 
Ticket URL: <http://dev.laptop.org/ticket/4476#comment:17>
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