I am quite new in the Ubuntu world and I have to say I love it.
Nevertheless I have an annoying problem with my wireless connection. In the last few days I did a lot of research on Internet and I found that many people are experiencing similar issues.
I have a Toshiba Portege M700 (Tablet) equipped with an Intel PRO/Wireless 4965 AG or AGN. I am running a 2.6.27-13 kernel with the latest version of (proposed) backports available, i.e. linux-backports-module-intrepid 188.8.131.52.16. I kept it updated because I was hoping that the wireless team managed to solve it. Unfortunately the problem still appears.
The problem is that my WPA-secured wireless connection stalls after a random period of time, which may be several minutes to several hours. The network manager does not report anything strange (it keeps saying that the connection is on) but I can't access the network anymore. Moreover, all the processes slow down and even executing a simple 'sudo something' may require several minutes.
I found that this phenomenon appears more frequently when there is intense wireless traffic (new hosts joining the network, big downloads, etc.). When my connection drops, I can try to restore it in several ways: sometimes it is sufficient to Disable and then Re-Enable the Wireless from the GUI Network Manager. Sometimes it is not enough and I have to remove the iwlagn module from the kernel and the re-add it. Other times (rarely) I need a complete reboot of my machine.
I report here also the last part of the dmesg output. I found that every time the connection drops I have the message 'iwlagn: Microcode SW error detected'.
[ 25.736987] iwlagn 0000:01:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[ 25.737105] iwlagn 0000:01:00.0: restoring config space at offset 0x1 (was 0x100002, writing 0x100006)
[ 25.737672] firmware: requesting lbm-iwlwifi-4965-2.ucode
[ 25.799634] iwlagn loaded firmware version 184.108.40.206
[ 26.004189] Registered led device: iwl-phy0:radio
[ 26.004397] Registered led device: iwl-phy0:assoc
[ 26.004516] Registered led device: iwl-phy0:RX
[ 26.004633] Registered led device: iwl-phy0:TX
[ 26.169528] NET: Registered protocol family 17
[ 27.309966] 0000:00:19.0: eth0: Link is Up 100 Mbps Full Duplex, Flow Control: None
[ 27.309980] 0000:00:19.0: eth0: 10/100 speed: disabling TSO
[ 55.348613] CPU0 attaching NULL sched-domain.
[ 55.348631] CPU1 attaching NULL sched-domain.
[ 55.352213] CPU0 attaching sched-domain:
[ 55.352223] domain 0: span 0-1 level MC
[ 55.352229] groups: 0 1
[ 55.352239] domain 1: span 0-1 level CPU
[ 55.352245] groups: 0-1
[ 55.352254] CPU1 attaching sched-domain:
[ 55.352259] domain 0: span 0-1 level MC
[ 55.352264] groups: 1 0
[ 55.352272] domain 1: span 0-1 level CPU
[ 55.352277] groups: 0-1
[ 56.766533] wlan0: authenticate with AP 00:1c:2e:67:d8:a4
[ 56.767783] wlan0: authenticated
[ 56.767795] wlan0: associate with AP 00:1c:2e:67:d8:a4
[ 56.777630] wlan0: RX AssocResp from 00:1c:2e:67:d8:a4 (capab=0x11 status=0 aid=2)
[ 56.777645] wlan0: associated
[ 56.817051] cfg80211: Calling CRDA for country: IT
[ 64.015675] NET: Registered protocol family 10
[ 64.016212] lo: Disabled Privacy Extensions
[ 74.096023] eth0: no IPv6 routers present
[ 77.410881] wlan0: authenticate with AP 00:1c:2e:67:c9:44
[ 77.417105] wlan0: authenticate with AP 00:1c:2e:67:c9:44
[ 77.417148] wlan0: authenticated
[ 77.417155] wlan0: associate with AP 00:1c:2e:67:c9:44
[ 77.424154] wlan0: authenticate with AP 00:1c:2e:67:c9:44
[ 77.424182] wlan0: authenticated
[ 77.424189] wlan0: associate with AP 00:1c:2e:67:c9:44
[ 77.428319] wlan0: RX ReassocResp from 00:1c:2e:67:c9:44 (capab=0x11 status=0 aid=3)
[ 77.428330] wlan0: associated
[ 126.252538] hda-intel: IRQ timing workaround is activated for card #0. Suggest a bigger bdl_pos_adj.
[ 2623.731800] iwlagn: Microcode SW error detected. Restarting 0x82000000.
[ 2623.755959] iwlagn: No space for Tx
[ 2623.755975] iwlagn: Error sending SENSITIVITY_CMD: enqueue_hcmd failed: -28
[ 2623.755980] iwlagn: SENSITIVITY_CMD failed
[ 2623.964537] Registered led device: iwl-phy0:radio
[ 2623.964588] Registered led device: iwl-phy0:assoc
[ 2623.964627] Registered led device: iwl-phy0:RX
[ 2623.964665] Registered led device: iwl-phy0:TX
[ 2637.150496] mac80211-phy0: failed to remove key (0, 00:1c:2e:67:c9:44) from hardware (-22)
[ 2637.157875] wlan0: authenticate with AP 00:1c:2e:67:c9:44
[ 2637.179284] wlan0: authenticate with AP 00:1c:2e:67:d8:a4
[ 2637.183131] wlan0: authenticate with AP 00:1c:2e:67:d8:a4
[ 2637.183157] wlan0: authenticated
Can anyone help me? Is there anything I may try?
I've read that the related kernel panic bug has been fixed (see https://bugs.launchpad.net/ubuntu/in...0?comments=all). What does it mean? "Fixed" means "solved"? If so, why I am experiencing the same Microcode SW error after the latest kernel and backports updates?
Many many thanks in advance to anyone will help me staying away from the MS world...