Connection Drops with Edimax EW-7811UN WiFi Adapter on Ubuntu 14.04.2 Kernel 3.16

[Geniusberry]

So I re-did the little experiment with the ethernet unplugged, and the resulting log is at http://paste.ubuntu.com/11506395/
It's weird though, in that when I tried to open the file up in gedit, it gave an error message saying that it had invalid characters. Less as well as Emacs show the same thing, a bunch of black unreadable characters, so I think the file might possibly be corrupted. It doesn't look like lwfinger's drivers are going too well. Any ideas for where to go next?

[chili555]

when I tried to open the file up in gedit, it gave an error message saying that it had invalid characters.

Which file? The dmesg you just pasted?

Studying...

EDIT: Was the device ever inserted? I see no driver or other sign of it. I do see:

Jun  1 17:38:14 hallinux kernel: [    0.284327] ACPI: PCI Interrupt Link [LNKA] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284400] ACPI: PCI Interrupt Link [LNKB] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284475] ACPI: PCI Interrupt Link [LNKC] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284541] ACPI: PCI Interrupt Link [LNKD] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284595] ACPI: PCI Interrupt Link [LNKE] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284638] ACPI: PCI Interrupt Link [LNKF] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284680] ACPI: PCI Interrupt Link [LNKG] (IRQs 4 5 7 10 11 14 15) *0
Jun  1 17:38:14 hallinux kernel: [    0.284723] ACPI: PCI Interrupt Link [LNKH] (IRQs 4 5 7 10 11 14 15) *0

Are the IRQs set to auto-select in the BIOS? I'd probably try it if not now set.

[Geniusberry]

The syslog file from /var/log/syslog was the one with the weird characters, and yes, the one I just posted. I'm 100% sure that the device was inserted, and that the posted log lines are the ones from right before I inserted the device to after I rebooted and then copied all of it. What do you mean by IRQ's? I haven't looked through the BIOS yet, but I'm willing it take a shot at it.

[chili555]

Here is a screen capture from a BIOS setup page. Although it is different from yours, I am pretty confident that you'll find a similar page. As you can see, the IRQs are set to auto select. Also, in some cases, previously reluctant wireless devices work better when the BIOS is reset to defaults.

http://en.wikipedia.org/wiki/Interru...rchitecture%29

[Geniusberry]

I reset the BIOS to default, but I can't seem to directly find the IRQ settings in my BIOS. The closest I could find was a hardware settings page with subsections on auto connecting PCI, PCI E, and other hardware, all of the settings which were set to auto, except for PS 2 port 60 and 64 emulation, which I doubt is the right setting. Still no luck when I inserted the driver however. At this point I'm about out of ideas with lwfinger's drivers. Any suggestions?

[chili555]

i regret that I have no other suggestions. Sorry.

[Geniusberry]

Earlier you mentioned something about making the default drivers work better for me. Is there anything that can be done in that avenue? I've also been looking up using ndiswrapper, and was wondering if it could be applicable in this case, as the adapter does have working Windows drivers, and apparently works with Windows XP, which is supposed to be the supported operating system drivers in ndiswrapper. At this point I'm split between just using Windows with this adapter, which I'm going to install anyway, throwing the adapter away, or trying a reinstall with just pure Ubuntu and crossing my fingers that the WiFi fixes will work. Thanks for all your help so far!

[chili555]

There is but one meaningful driver parameter available in the in-kernel rtl8192cu:

$ modinfo rtl8192cu
filename:       /lib/modules/4.0.1-040001-generic/kernel/drivers/net/wireless/rtlwifi/rtl8192cu/rtl8192cu.ko
firmware:       rtlwifi/rtl8192cufw_TMSC.bin
firmware:       rtlwifi/rtl8192cufw_B.bin
firmware:       rtlwifi/rtl8192cufw_A.bin
firmware:       rtlwifi/rtl8192cufw.bin
description:    Realtek 8192C/8188C 802.11n USB wireless
license:        GPL
author:         Larry Finger	<Larry.Finger@lwfinger.net>
author:         Ziv Huang	<ziv_huang@realtek.com>
author:         Georgia		<georgia@realtek.com>
<snip>
depends:        rtlwifi,rtl8192c-common,rtl_usb,mac80211
intree:         Y
vermagic:       4.0.1-040001-generic SMP mod_unload modversions 
signer:         Magrathea: Glacier signing key
sig_key:        58:EF:1B:E8:6F:69:F6:97:25:C1:20:58:C9:00:5C:68:4C:A0:4C:FB
sig_hashalgo:   sha512
parm:           swenc:Set to 1 for software crypto (default 0) (bool)
parm:           debug:Set debug level (0-5) (default 0) (int)

We may as well try it:

sudo -i
echo "options rtl8192cu swenc=1"  >>  /etc/modprobe.d/rtl8192cu.conf
exit

Reboot. Any improvement?

throwing the adapter away

Now we're getting somewhere!

ndiswrapper is an option and requires XP drivers, usually .inf and .sys, appropriate to your architecture; either 32- or 64-bit.

[Geniusberry]

I changed the option like you said, and unfortunately, no luck. However, now even without lwfinger's drivers installed, my system will just freeze up whenever I plug the adapter in. I'm curious about trying out ndiswrapper, but I'm not sure what to do with the in kernel drivers right now. Any suggestions?

[chili555]

However, now even without lwfinger's drivers installed, my system will just freeze up whenever I plug the adapter in.

Something else is horribly wrong then. Generally, the rt28xx suite of drivers is reliable if sometimes tricky to get and stay connected. I have never before now heard of a case where the whole computer simply locked up! Unfortunately, we haven't yet been able to see any sign of the lock-up in the logs. Until we do, we are powerless to troubleshoot it. I suggested a method in a post above, however, the logs you retrieved yielded nothing remarkable.

Do you have an earlier kernel available at the GRUB menu upon booting? Is the behavior the same with any kernel?