Re: iwl3945: disassociating from current AP on rescan with kernels > 3.0

On Thu, Dec 29, 2011 at 05:46:48PM -0500, Mike Edenfield wrote:

After upgrading to a v3.0 kernel, my Intel wireless adapter stopped working
when used with any UI-based wpa_supplicant front-end that does periodic
scans, such as NetworkManager and wicd. Whenever the software asks for an AP
scan, the device disconnects from its current AP and blacklists it, making
it impossible to reconnect until I kill wpa_supplicant. If I manually
configure wpa_supplicant and launch it directly, the adapter stays
associated with the AP properly.

I was able to reproduct this behavior with kernel version 3.0.4, 3.1.4, and
3.1.5, but downgrading to 2.6.39 or lower solves the problem. I haven't seen
any other reports of this problem specific to 3.x -- did I miss some other
step I need to do when upgrading?

Are you sure this is 2.6.39 -> 3.0 regression. There are not many
changes in iwlegacy driver between these

$ git log v2.6.39..v3.0 --oneline --no-merges -- drivers/net/wireless/iwlegacy/
51e6525 iwlegacy: fix channel switch locking
51892db iwl4965: set tx power after rxon_assoc
dfe2158 iwl4965: correctly validate temperature value
aac11c1 iwl4965: fix 5GHz operation
8220ba3 iwlegacy: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
2245090 iwlegacy: remove sync_cmd_mutex
28a6e57 iwlegacy: more priv->mutex serialization
81e6326 iwlegacy: fix enqueue hcmd race conditions
93fd74e iwlegacy: comment typo fix diable -> disable
7a55237 iwlegacy: remove scan_tx_antennas
5855c7d iwlegacy: remove unneeded __packed
8eb0ac7 iwlegacy: remove unneeded disable_hw_scan check
3e41de8 iwlegacy: simplify init geos
a078a1f iwlegacy: enable only rfkill interrupt when device is down
ab42b40 iwlegacy: remove duplicate initialization in iwl4956_down()
85ee7a1 treewide: cleanup continuations and remove logging message whitespace
0477ad7 iwlegacy: use pci_dev->revision
a22e93f iwl4965: drop a lone pr_err()

and none of it looks suspicious.

Problem looks more like software scanning issue, which we enable
by default on 2.6.39. Can you check if disable_hw_scan=0 module
parameter helps?

Thanks
Stanislaw