Re: panic when removing pccard

In message: <466913F0.2060200_at_cytexbg.com>
            Niki Denev <nike_d_at_cytexbg.com> writes:
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: I experience the following panic on a few days old -current :
: 
: If i insert and then remove a pcmcia card using the ubsa module
: (Vodafone Mobile Connect, which actually is Huawei E630 UMTS/HSDPA modem)
: the machine panics, because i think the order of removal of the devices
: by the kernel is not correct. I'm not sure because i don't have -STABLE
: machine with pcmcia now, but i think this problem does not exist there.
: 
: Here is what happens when card is inserted :
: 
: ohci0: <NEC uPD 9210 USB controller> mem 0xc0212000-0xc0212fff irq 11 at
: device 0.0 on cardbus0
: ohci0: [GIANT-LOCKED]
: ohci0: [ITHREAD]
: usb4: OHCI version 1.0
: usb4: <NEC uPD 9210 USB controller> on ohci0
: usb4: USB revision 1.0
: uhub4: <NEC OHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb4
: uhub4: 1 port with 1 removable, self powered
: ohci1: <NEC uPD 9210 USB controller> mem 0xc0213000-0xc0213fff irq 11 at
: device 0.1 on cardbus0
: ohci1: [GIANT-LOCKED]
: ohci1: [ITHREAD]
: usb5: OHCI version 1.0
: usb5: <NEC uPD 9210 USB controller> on ohci1
: usb5: USB revision 1.0
: uhub5: <NEC OHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb5
: uhub5: 1 port with 1 removable, self powered
: ucom0: <HUAWEI Technologies HUAWEI Mobile, class 0/0, rev 1.10/0.00,
: addr 2> on uhub4
: ucom0: HUAWEI Technologies HUAWEI Mobile, rev 1.10/0.00, addr 2
: 
: Then card eject :
: 
: ucom0: detached
: (null): at uhub4 port 1 (addr 2) disconnected
: 
: 
: Fatal trap 12: page fault while in kernel mode
: fault virtual address   = 0x400
: fault code              = supervisor read, page not present
: instruction pointer     = 0x20:0xc0661e84
: stack pointer           = 0x28:0xd4d63b4c
: frame pointer           = 0x28:0xd4d63b6c
: code segment            = base 0x0, limit 0xfffff, type 0x1b
:                         = DPL 0, pres 1, def32 1, gran 1
: processor eflags        = interrupt enabled, resume, IOPL = 0
: current process         = 31 (cbb0 event thread)
: [thread pid 31 tid 100027 ]
: Stopped at kobj_delete+0x14:      movl    0x400(%eax),%ebx
: db> bt
: Tracing pid 31 tid 100027 td 0xc2a76440
: kobj_delete(c2ef0000,c0955ce0,c2ef0000cc2eeee00,d4d63bac,...) at
: kobj_delete+0x14
: device_delete_child(c2eef400,c2ef0000,c2bdfc80,c2bdfc80,4,...) at
: device_delete_child+0x94
: usb_disconnect_port(c2eefab0,c2eef400,c0955c60,c2bdfbd0,c2eefa80,...) at
: usb_disconnect_port+0xdc
: uhub_detach(c2eef400,c29c6850,c094c12c,d4d63c00,c065ca19,...) at
: uhub_detach+0x74
: device_detach(c2eef400,c2ef0000,c2ef3000,c2eef200,d4d63c30,...) at
: device_detach+0x68
: device_delete_child(c2eef200,c2eef400,c2ef3000,c2eeed00,d4d63c50,...) at
: device_delete_child+0x31
: device_delete_child(c2eeed00,c2eef200,c2935060,d4d63c50,c2eeed00,...) at
: device_delete_child+0x1c
: ohci_pci_detach(c2eeed00,c29b5050,c094c12c,c065a875,8,...) at
: ohci_pci_detach+0xb1
: device_detach(c2eeed00,d4d63cb0,d4d63cb4,c2a76440,d4d63cc4,...) at
: device_detach+0x68
: cardbus_detach_card(c2a7aa80,c2a5bbd4,fa,202,0,...) at
: cardbus_detach_card+0xcd
: cbb_event_thread(c2a5b800,d4d63d38,0,0,0,...) at cbb_event_thread+0x1a9
: fork_exit(c05643a0,c2a5b800,d4d63d38) at fork_exit+0x2a
: fork_trampoline() at fork_trampoline+0x8
: - --- trap 0, eip = 0, esp = 0xd4d63d70, ebp = 0 ---
: db>

I'll take a look at this problem.  The one difference between what you
are doing and what I do all the time is that you have devices plugged
into your usb bus and I don't.  Given the name of the card, I suspect
that's because they are soldered onto the usb bus.

We need to solve this problem for 7.0, I think.

Warner