netfront smartpoll leaves timer interrupt enabled after xenbus disconnect

netfront smartpoll leaves timer interrupt enabled after xenbus disconnect

[Jeremy Fitzhardinge]

  Hi Dongxiao,

It looks like the smartpoll code never disables its timer interrupt.  
Ian Jackson found that this causes a crash (see below) during domain 
suspend/resume; I suspect this is because on resume the timer interrupt 
triggers, but the network device has not yet reinitialized itself.

Could you have a look at fixing this?

Thanks,
     J

[   63.681260] BUG: unable to handle kernel NULL pointer dereference at 
00000010
[   63.681293] IP: [<c1300381>] smart_poll_function+0xbb/0xf2
[   63.681320] *pdpt = 000000001fee5027 *pde = 0000000000000000
[   63.681344] Oops: 0000 [#1] SMP
[   63.681362] last sysfs file: /sys/kernel/uevent_seqnum
[   63.681376] Modules linked in: [last unloaded: scsi_wait_scan]
[   63.681398]
[   63.681410] Pid: 5, comm: events/0 Not tainted (2.6.32.16 #1)
[   63.681424] EIP: 0061:[<c1300381>] EFLAGS: 00010002 CPU: 0
[   63.681438] EIP is at smart_poll_function+0xbb/0xf2
[   63.681451] EAX: 00000000 EBX: dfea8320 ECX: 00000001 EDX: 00000062
[   63.681465] ESI: 00000064 EDI: 00000000 EBP: df849cfc ESP: df849cdc
[   63.681479]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0069
[   63.681493] Process events/0 (pid: 5, ti=df848000 task=df839480 
task.ti=df848000)
[   63.681508] Stack:
[   63.681516]  dfeac828 00000002 dfeac828 dfea8368 dfea0068 0000002c 
dfeac828 c13002c6
[   63.681555]<0>  df849d1c c1079ab8 df849d48 c2386358 c2386328 0000002c 
00000000 c2386328
[   63.681598]<0>  df849d5c c1079ce8 000028cd 88bbcad9 d3b2cae7 0000000e 
d3b2cae7 0000000e
[   63.681646] Call Trace:
[   63.681662]  [<c13002c6>] ? smart_poll_function+0x0/0xf2
[   63.681683]  [<c1079ab8>] ? __run_hrtimer+0xa9/0xf6
[   63.681701]  [<c1079ce8>] ? hrtimer_interrupt+0xcd/0x1c8
[   63.681719]  [<c102cef0>] ? xen_timer_interrupt+0x2b/0x224
[   63.681737]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.681755]  [<c102d2ac>] ? check_events+0x8/0xc
[   63.681776]  [<c102d2a3>] ? xen_restore_fl_direct_end+0x0/0x1
[   63.681795]  [<c14d1471>] ? _spin_unlock_irqrestore+0x2f/0x31
[   63.681814]  [<c105eb9e>] ? try_to_wake_up+0x2fa/0x304
[   63.681832]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.681850]  [<c10a0cc4>] ? handle_IRQ_event+0x5f/0x122
[   63.681867]  [<c10a233f>] ? handle_level_irq+0x58/0xa9
[   63.681886]  [<c121983d>] ? __xen_evtchn_do_upcall+0xab/0x131
[   63.681904]  [<c1219c71>] ? xen_evtchn_do_upcall+0x20/0x30
[   63.682179]  [<c102ffe7>] ? xen_do_upcall+0x7/0xc
[   63.682179]  [<c102007b>] ? apic_reg_write+0xa5/0x52f
[   63.682179]  [<c1002227>] ? hypercall_page+0x227/0x1005
[   63.682179]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.682179]  [<c102d2ac>] ? check_events+0x8/0xc
[   63.682179]  [<c102d26b>] ? xen_irq_enable_direct_end+0x0/0x1
[   63.682179]  [<c105cd0d>] ? finish_task_switch+0x4f/0xa6
[   63.682179]  [<c14d0186>] ? schedule+0x7dd/0x861
[   63.682179]  [<c106dd9d>] ? __mod_timer+0x135/0x140
[   63.682179]  [<c102d2ac>] ? check_events+0x8/0xc
[   63.682179]  [<c102d2a3>] ? xen_restore_fl_direct_end+0x0/0x1
[   63.682179]  [<c14d1471>] ? _spin_unlock_irqrestore+0x2f/0x31
[   63.682179]  [<c107750b>] ? prepare_to_wait+0x43/0x48
[   63.682179]  [<c10742a2>] ? worker_thread+0x94/0x1d2
[   63.682179]  [<c10ccd2d>] ? vmstat_update+0x0/0x2f
[   63.682179]  [<c1077357>] ? autoremove_wake_function+0x0/0x33
[   63.682179]  [<c107420e>] ? worker_thread+0x0/0x1d2
[   63.682179]  [<c1077120>] ? kthread+0x61/0x66
[   63.682179]  [<c10770bf>] ? kthread+0x0/0x66
[   63.682179]  [<c102ff97>] ? kernel_thread_helper+0x7/0x10
[   63.682179] Code: c6 89 d0 31 d2 f7 f6 85 d2 75 1a 85 c9 75 0c 8b
  83 90 08 00 00 c6 40 10 00 eb 32 c7 83 54 45 00 00 00 00 00 00 8b 83 90
  08 00 00<80>  78 10 00 74 1c 8b 4d e8 b8 00 ca 9a 3b 31 d2 f7 71
44 31 c9
[   63.682179] EIP: [<c1300381>] smart_poll_function+0xbb/0xf2 SS:ESP 
0069:df849cdc
[   63.682179] CR2: 0000000000000010
[   63.682179] ---[ end trace 760037e75e5675c8 ]---
[   63.682179] Kernel panic - not syncing: Fatal exception in interrupt
[   63.682179] Pid: 5, comm: events/0 Tainted: G      D    2.6.32.16 #1
[   63.682179] Call Trace:
[   63.682179]  [<c14cf7b1>] ? printk+0xf/0x11
[   63.682179]  [<c14cf6ee>] panic+0x39/0xed
[   63.682179]  [<c14d2085>] oops_end+0xa1/0xb0
[   63.682179]  [<c104b426>] no_context+0x137/0x141
[   63.682179]  [<c104b56f>] __bad_area_nosemaphore+0x13f/0x147
[   63.682179]  [<c104b584>] bad_area_nosemaphore+0xd/0x10
[   63.682179]  [<c14d3275>] do_page_fault+0x1c6/0x32b
[   63.682179]  [<c14d30af>] ? do_page_fault+0x0/0x32b
[   63.682179]  [<c14d16c6>] error_code+0x66/0x6c
[   63.682179]  [<c14d30af>] ? do_page_fault+0x0/0x32b
[   63.682179]  [<c1300381>] ? smart_poll_function+0xbb/0xf2
[   63.682179]  [<c13002c6>] ? smart_poll_function+0x0/0xf2
[   63.682179]  [<c1079ab8>] __run_hrtimer+0xa9/0xf6
[   63.682179]  [<c1079ce8>] hrtimer_interrupt+0xcd/0x1c8
[   63.682179]  [<c102cef0>] xen_timer_interrupt+0x2b/0x224
[   63.682179]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.682179]  [<c102d2ac>] ? check_events+0x8/0xc
[   63.682179]  [<c102d2a3>] ? xen_restore_fl_direct_end+0x0/0x1
[   63.682179]  [<c14d1471>] ? _spin_unlock_irqrestore+0x2f/0x31
[   63.682179]  [<c105eb9e>] ? try_to_wake_up+0x2fa/0x304
[   63.682179]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.682179]  [<c10a0cc4>] handle_IRQ_event+0x5f/0x122
[   63.682179]  [<c10a233f>] handle_level_irq+0x58/0xa9
[   63.682179]  [<c121983d>] __xen_evtchn_do_upcall+0xab/0x131
[   63.682179]  [<c1219c71>] xen_evtchn_do_upcall+0x20/0x30
[   63.682179]  [<c102ffe7>] xen_do_upcall+0x7/0xc
[   63.682179]  [<c102007b>] ? apic_reg_write+0xa5/0x52f
[   63.682179]  [<c1002227>] ? hypercall_page+0x227/0x1005
[   63.682179]  [<c102cb3f>] ? xen_force_evtchn_callback+0xf/0x14
[   63.682179]  [<c102d2ac>] check_events+0x8/0xc
[   63.682179]  [<c102d26b>] ? xen_irq_enable_direct_end+0x0/0x1
[   63.682179]  [<c105cd0d>] ? finish_task_switch+0x4f/0xa6
[   63.682179]  [<c14d0186>] schedule+0x7dd/0x861
[   63.682179]  [<c106dd9d>] ? __mod_timer+0x135/0x140
[   63.682179]  [<c102d2ac>] ? check_events+0x8/0xc
[   63.682179]  [<c102d2a3>] ? xen_restore_fl_direct_end+0x0/0x1
[   63.682179]  [<c14d1471>] ? _spin_unlock_irqrestore+0x2f/0x31
[   63.682179]  [<c107750b>] ? prepare_to_wait+0x43/0x48
[   63.682179]  [<c10742a2>] worker_thread+0x94/0x1d2
[   63.682179]  [<c10ccd2d>] ? vmstat_update+0x0/0x2f
[   63.682179]  [<c1077357>] ? autoremove_wake_function+0x0/0x33
[   63.682179]  [<c107420e>] ? worker_thread+0x0/0x1d2
[   63.682179]  [<c1077120>] kthread+0x61/0x66
[   63.682179]  [<c10770bf>] ? kthread+0x0/0x66
[   63.682179]  [<c102ff97>] kernel_thread_helper+0x7/0x10