In kernels 3.2.0 and later, the staging driver r8712u does not work when wicd is used to control wireless networking. The problem was bisected to commit a5ee652. The logs show a locking problem in wpa_supplicant, as shown below. kernel: [ 480.380063] wpa_supplicant D ffff88002ec40b60 0 5092 1 0x00000000 kernel: [ 480.380067] ffff88006b307ca8 0000000000000082 ffffffff8164e440 ffffea00004d81f0 kernel: [ 480.380070] ffff88002ec407c0 ffff88006b307fd8 ffff88006b307fd8 ffff88006b307fd8 kernel: [ 480.380073] ffff88006b278680 ffff88002ec407c0 ffff88006d437200 0000000000000000 kernel: [ 480.380076] Call Trace: kernel: [ 480.380083] [<ffffffff813d117a>] schedule+0x3a/0x50 kernel: [ 480.380086] [<ffffffff813d1f75>] __mutex_lock_slowpath+0xe5/0x170 kernel: [ 480.380088] [<ffffffff813d1b0d>] mutex_lock+0x1d/0x40 kernel: [ 480.380091] [<ffffffff81336d40>] rtnl_lock+0x10/0x20 kernel: [ 480.380094] [<ffffffff813b5452>] wext_handle_ioctl+0x62/0x250 kernel: [ 480.380097] [<ffffffff8132bfeb>] dev_ioctl+0xdb/0x5f0 kernel: [ 480.380101] [<ffffffff810f943f>] ? tlb_finish_mmu+0xf/0x40 kernel: [ 480.380105] [<ffffffff81312ddd>] sock_ioctl+0x10d/0x2d0 kernel: [ 480.380108] [<ffffffff8112c5be>] do_vfs_ioctl+0x8e/0x510 kernel: [ 480.380111] [<ffffffff8112cad1>] sys_ioctl+0x91/0xa0 kernel: [ 480.380113] [<ffffffff813dadd2>] system_call_fastpath+0x16/0x1b
Created attachment 72480 [details] Patch to fix locking problem when using wicd
Why are you using bugzilla for patches, please just use the mailing list, we can't do anything with patches here, you know better :)
Of course I know better. Putting it here was just in case some other user runs across the problem before I push the "real" patch to you. I'm waiting for some testing - I only found the bug 3 hours ago.
A patch referencing this bug report has been merged in Linux v3.4-rc1: commit 9f4bc8cf3fe750ed093856a5f5d41c11cc12ad22 Author: Larry Finger <Larry.Finger@lwfinger.net> Date: Sat Feb 25 18:10:20 2012 -0600 staging: r8712u: Fix regression introduced by commit a5ee652