Hi, while doing my first steps under d80211 I stumbled over a soft lockup. It's on a real SMP machine (Core 2 Duo). After the lockup the machine becomes unusable. I can reproduce it reliably by unplugging the device.
The bug appears to be present in the John Linville's wireless-dev master branch, but also in Micheal Wu's zd1211rw-week51 branch. Reading the code I see that the work structs are canceled more then one time. At first in ieee80211_unregister_hw and second in ieee80211_if_shutdown called by unregister_netdev. The second cancel operation casues the soft lockup. Does anybody have an idea how to fix it? Here is the kernel log with the soft lockup. Ja 6 13:13:26 newa kernel: [ 152.647382] BUG: soft lockup detected on CPU#0! Jan 6 13:13:26 newa kernel: [ 152.647390] Jan 6 13:13:26 newa kernel: [ 152.647391] Call Trace: Jan 6 13:13:26 newa kernel: [ 152.647410] [show_trace+65/112] show_trace+0x41/0x70 Jan 6 13:13:26 newa kernel: [ 152.647419] [dump_stack+18/32] dump_stack+0x12/0x20 Jan 6 13:13:26 newa kernel: [ 152.647429] [softlockup_tick+250/288] softlockup_tick+0xfa/0x120 Jan 6 13:13:26 newa kernel: [ 152.647439] [update_process_times+87/144] update_process_times+0x57/0x90 Jan 6 13:13:26 newa kernel: [ 152.647448] [smp_local_timer_interrupt+52/96] smp_local_timer_interrupt+0x34/0x60 Jan 6 13:13:26 newa kernel: [ 152.647457] [smp_apic_timer_interrupt+89/128] smp_apic_timer_interrupt+0x59/0x80 Jan 6 13:13:26 newa kernel: [ 152.647465] [apic_timer_interrupt+102/112] apic_timer_interrupt+0x66/0x70 Jan 6 13:13:26 newa kernel: [ 152.648225] DWARF2 unwinder stuck at apic_timer_interrupt+0x66/0x70 Jan 6 13:13:26 newa kernel: [ 152.648229] Jan 6 13:13:26 newa kernel: [ 152.648232] Leftover inexact backtrace: Jan 6 13:13:26 newa kernel: [ 152.648233] Jan 6 13:13:26 newa kernel: [ 152.648237] <IRQ> <EOI> [lock_timer_base+64/96] lock_timer_base+0x40/0x60 Jan 6 13:13:26 newa kernel: [ 152.648268] [try_to_del_timer_sync+24/96] try_to_del_timer_sync+0x18/0x60 Jan 6 13:13:26 newa kernel: [ 152.648277] [del_timer_sync+12/32] del_timer_sync+0xc/0x20 Jan 6 13:13:26 newa kernel: [ 152.648301] [_end+129730637/2130872328] :80211:ieee80211_if_shutdown+0x75/0x100 Jan 6 13:13:26 newa kernel: [ 152.648323] [_end+129745001/2130872328] :80211:ieee80211_stop+0x101/0x120 Jan 6 13:13:26 newa kernel: [ 152.648334] [dev_close+88/128] dev_close+0x58/0x80 Jan 6 13:13:26 newa kernel: [ 152.648341] [unregister_netdevice+149/592] unregister_netdevice+0x95/0x250 Jan 6 13:13:26 newa kernel: [ 152.648363] [_end+129742664/2130872328] :80211:ieee80211_unregister_hw+0x90/0x220 Jan 6 13:13:26 newa kernel: [ 152.648382] [_end+129956419/2130872328] :zd1211rw_d80211:disconnect+0xab/0x120 Jan 6 13:13:26 newa kernel: [ 152.648412] [_end+128711626/2130872328] :usbcore:usb_unbind_interface+0x72/0xe0 Jan 6 13:13:26 newa kernel: [ 152.648423] [__device_release_driver+135/208] __device_release_driver+0x87/0xd0 Jan 6 13:13:26 newa kernel: [ 152.648431] [device_release_driver+51/96] device_release_driver+0x33/0x60 Jan 6 13:13:26 newa kernel: [ 152.648438] [bus_remove_device+137/176] bus_remove_device+0x89/0xb0 Jan 6 13:13:26 newa kernel: [ 152.648446] [device_del+419/496] device_del+0x1a3/0x1f0 Jan 6 13:13:26 newa kernel: [ 152.648472] [_end+128700218/2130872328] :usbcore:usb_disable_device+0x82/0x100 Jan 6 13:13:26 newa kernel: [ 152.648499] [_end+128684210/2130872328] :usbcore:usb_disconnect+0xaa/0x110 Jan 6 13:13:26 newa kernel: [ 152.648526] [_end+128687990/2130872328] :usbcore:hub_thread+0x48e/0xd20 Jan 6 13:13:26 newa kernel: [ 152.648537] [thread_return+0/237] thread_return+0x0/0xed Jan 6 13:13:26 newa kernel: [ 152.648551] [autoremove_wake_function+0/48] autoremove_wake_function+0x0/0x30 Jan 6 13:13:26 newa kernel: [ 152.648579] [_end+128686824/2130872328] :usbcore:hub_thread+0x0/0xd20 Jan 6 13:13:26 newa kernel: [ 152.648587] [keventd_create_kthread+0/128] keventd_create_kthread+0x0/0x80 Jan 6 13:13:26 newa kernel: [ 152.648594] [kthread+217/288] kthread+0xd9/0x120 Jan 6 13:13:26 newa kernel: [ 152.648604] [child_rip+10/18] child_rip+0xa/0x12 Jan 6 13:13:26 newa kernel: [ 152.648611] [keventd_create_kthread+0/128] keventd_create_kthread+0x0/0x80 Jan 6 13:13:26 newa kernel: [ 152.648620] [flat_send_IPI_mask+0/80] flat_send_IPI_mask+0x0/0x50 Jan 6 13:13:26 newa kernel: [ 152.648630] [kthread+0/288] kthread+0x0/0x120 Jan 6 13:13:26 newa kernel: [ 152.648637] [child_rip+0/18] child_rip+0x0/0x12 Jan 6 13:13:26 newa kernel: [ 152.648643] Uli -- Uli Kunitz - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
