It trigger a kernel oops:
Note the: "CPU: 0 PID: 2354 Comm: gajim Tainted: P           OE  3.19.0-16-generic #16-Ubuntu"


May  7 10:50:40 Laptop-cm kernel: [   28.446592] BUG: unable to handle kernel NULL pointer dereference at 0000000000000293
May  7 10:50:40 Laptop-cm kernel: [   28.447134] IP: [<ffffffff817c6ef8>] __down+0x48/0xe0
May  7 10:50:40 Laptop-cm kernel: [   28.447677] PGD 1ee073067 PUD 1ee033067 PMD 0▓
May  7 10:50:40 Laptop-cm kernel: [   28.448241] Oops: 0002 [#1] SMP▓
May  7 10:50:40 Laptop-cm kernel: [   28.448765] Modules linked in: ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 pci_stub nf_defrag_ipv4 vboxpci(OE) vboxnetadp(OE) nf_nat_ipv4 vboxnetflt(OE) nf_nat nf_conntrack ip_tables x_tables vboxdrv(OE) binfmt_misc rfcomm bnep nls_iso8859_1 dell_wmi sparse_keymap dell_laptop snd_hda_codec_hdmi dcdbas snd_hda_codec_idt snd_hda_codec_generic i8k intel_rapl iosf_mbi x86_pkg_temp_thermal intel_powerclamp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd wl(POE) snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_pcm btusb bluetooth snd_seq_midi snd_seq_midi_event snd_rawmidi joydev snd_seq serio_raw snd_seq_device cfg80211 snd_timer hid_logitech_hidpp lpc_ich i915 snd soundcore shpchp mei_me drm_kms_helper mei drm i2c_algo_bit wmi 8250_fintek dell_smo8800 video mac_hid coretemp parport_pc ppdev lp parport autofs4 hid_logitech_dj usbhid hid psmouse e1000e ahci sdhci_pci libahci sdhci ptp pps_core
May  7 10:50:40 Laptop-cm kernel: [   28.453288] CPU: 0 PID: 2354 Comm: gajim Tainted: P           OE  3.19.0-16-generic #16-Ubuntu
May  7 10:50:40 Laptop-cm kernel: [   28.453976] Hardware name: Dell Inc. Latitude E6330/030XCG, BIOS A10 05/20/2013
May  7 10:50:40 Laptop-cm kernel: [   28.454674] task: ffff880211793110 ti: ffff880211744000 task.ti: ffff880211744000
May  7 10:50:40 Laptop-cm kernel: [   28.455377] RIP: 0010:[<ffffffff817c6ef8>]  [<ffffffff817c6ef8>] __down+0x48/0xe0
May  7 10:50:40 Laptop-cm kernel: [   28.456082] RSP: 0018:ffff880211747e18  EFLAGS: 00010086
May  7 10:50:40 Laptop-cm kernel: [   28.456780] RAX: 0000000000000293 RBX: ffff880211747f78 RCX: ffff880211747f80
May  7 10:50:40 Laptop-cm kernel: [   28.457510] RDX: ffff880211747e18 RSI: 0000000002b91754 RDI: ffff880211747f78
May  7 10:50:40 Laptop-cm kernel: [   28.458221] RBP: ffff880211747e58 R08: ffff8800d3189900 R09: 0000000000000000
May  7 10:50:40 Laptop-cm kernel: [   28.458934] R10: 0000000000000292 R11: 0000000000000293 R12: 7fffffffffffffff
May  7 10:50:40 Laptop-cm kernel: [   28.459638] R13: ffff880211793110 R14: 0000000000000002 R15: 00000000026320a0
May  7 10:50:40 Laptop-cm kernel: [   28.460339] FS:  00007f59a22ba700(0000) GS:ffff88021e200000(0000) knlGS:0000000000000000
May  7 10:50:40 Laptop-cm kernel: [   28.461050] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
May  7 10:50:40 Laptop-cm kernel: [   28.461786] CR2: 0000000000000293 CR3: 00000001ee076000 CR4: 00000000001407f0
May  7 10:50:40 Laptop-cm kernel: [   28.462510] Stack:
May  7 10:50:40 Laptop-cm kernel: [   28.463231]  ffff880211747f80 0000000000000293 0000000011747e88 ffff8800d3189910
May  7 10:50:40 Laptop-cm kernel: [   28.463969]  ffff880211747f78 0000000002b91754 ffff880211747f50 0000000000001000
May  7 10:50:40 Laptop-cm kernel: [   28.464733]  ffff880211747e88 ffffffff810bcd24 0000000000000000 0000000000000292
May  7 10:50:40 Laptop-cm kernel: [   28.465500] Call Trace:
May  7 10:50:40 Laptop-cm kernel: [   28.466242]  [<ffffffff810bcd24>] down+0x44/0x50
May  7 10:50:40 Laptop-cm kernel: [   28.467015]  [<ffffffffc0a3aee9>] wl_proc_read+0x89/0xa0 [wl]
May  7 10:50:40 Laptop-cm kernel: [   28.467772]  [<ffffffff813129e4>] ? security_file_permission+0x84/0xa0
May  7 10:50:40 Laptop-cm kernel: [   28.468534]  [<ffffffff8125aeb8>] proc_reg_read+0x48/0x70
May  7 10:50:40 Laptop-cm kernel: [   28.469318]  [<ffffffff811f3df8>] __vfs_read+0x18/0x50
May  7 10:50:40 Laptop-cm kernel: [   28.470076]  [<ffffffff811f3eba>] vfs_read+0x8a/0x140
May  7 10:50:40 Laptop-cm kernel: [   28.470831]  [<ffffffff811f3fb6>] SyS_read+0x46/0xb0
May  7 10:50:40 Laptop-cm kernel: [   28.471587]  [<ffffffff817c934d>] system_call_fastpath+0x16/0x1b
May  7 10:50:40 Laptop-cm kernel: [   28.472348] Code: 40 b9 00 00 48 83 ec 20 48 8b 47 10 48 89 4d c0 48 89 57 10 48 89 fb 49 bc ff ff ff ff ff ff ff 7f 41 be 02 00 00 00 48 89 45 c8 <48> 89 10 4c 89 6d d0 c6 45 d8 00 0f 1f 44 00 00 49 c7 45 00 02▓
May  7 10:50:40 Laptop-cm kernel: [   28.474091] RIP  [<ffffffff817c6ef8>] __down+0x48/0xe0
May  7 10:50:40 Laptop-cm kernel: [   28.474934]  RSP <ffff880211747e18>
May  7 10:50:40 Laptop-cm kernel: [   28.475769] CR2: 0000000000000293
May  7 10:50:40 Laptop-cm kernel: [   28.479847] ---[ end trace 8474f9c3396f1cf0 ]---