Hi Emmanuel, On Wed, Jul 10, 2013 at 2:55 AM, Grumbach, Emmanuel <emmanuel.grumbach@xxxxxxxxx> wrote: >> >> Emmanuel, >> >> Thank you for your quick response! >> >> It is a regression. I regularly had 300 Mbps speeds on this very access point, >> but it was years ago, in the 2.6 kernel series. However, I believe, from >> extensive online searches, that Intel has disabled the N functionality in the >> firmware on Linux, ostensibly until they (you? :-) >> ) can fix whatever problem they were seeing. With the demise of the Intel >> Linux Wireless bug tracker, though, public tracking of the bug has been >> impossible. There are now-dead links to the defunct bug tracker over this >> very issue. >> > > 11n hasn't been disabled in firmware, but rather in driver. > There is a bug we know about the "fail to flush tx fifo" thing that people reports (through mailing list or bugzilla of RedHat). > Can you please send the output of the kerne log (dmesg)? > I've been also experiencing the "fail to flush tx fifo" bug for a long time, so I'll provide my environment and logs in case it's helpful: - System: Thinkpad T410 - Chipset: Intel Corporation Centrino Advanced-N 6200 [8086:4239] (rev 35) - Kernel: 3.10.0 x86_64 (tried 3.2, 3.5, 3.8 and 3.9 also. It got a lot better on 3.10 btw) - Firmware: 9.221.4.1 build 25532 - AP: Linksys E1200 fw ver 1.0.00 build 11 (but happens also with other N AP's) - Log on dmesg: this repeated 12 times when I booted and connected to my wifi network [ 19.576029] iwlwifi 0000:03:00.0: fail to flush all tx fifo queues Q 0 [ 19.576039] iwlwifi 0000:03:00.0: Current SW read_ptr 3 write_ptr 4 [ 19.576089] iwl data: 00000000: 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 19.576125] iwlwifi 0000:03:00.0: FH TRBs(0) = 0x00000000 [ 19.576183] iwlwifi 0000:03:00.0: FH TRBs(1) = 0x80102004 [ 19.576196] iwlwifi 0000:03:00.0: FH TRBs(2) = 0x00000000 [ 19.576209] iwlwifi 0000:03:00.0: FH TRBs(3) = 0x80300003 [ 19.576222] iwlwifi 0000:03:00.0: FH TRBs(4) = 0x00000000 [ 19.576235] iwlwifi 0000:03:00.0: FH TRBs(5) = 0x00000000 [ 19.576248] iwlwifi 0000:03:00.0: FH TRBs(6) = 0x00000000 [ 19.576261] iwlwifi 0000:03:00.0: FH TRBs(7) = 0x00704040 [ 19.576317] iwlwifi 0000:03:00.0: Q 0 is active and mapped to fifo 3 ra_tid 0x0000 [3,4] [ 19.576373] iwlwifi 0000:03:00.0: Q 1 is active and mapped to fifo 2 ra_tid 0x0000 [0,0] [ 19.576429] iwlwifi 0000:03:00.0: Q 2 is active and mapped to fifo 1 ra_tid 0x0000 [4,5] [ 19.576484] iwlwifi 0000:03:00.0: Q 3 is active and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576540] iwlwifi 0000:03:00.0: Q 4 is active and mapped to fifo 7 ra_tid 0x0000 [65,65] [ 19.576595] iwlwifi 0000:03:00.0: Q 5 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576651] iwlwifi 0000:03:00.0: Q 6 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576705] iwlwifi 0000:03:00.0: Q 7 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576761] iwlwifi 0000:03:00.0: Q 8 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576815] iwlwifi 0000:03:00.0: Q 9 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576871] iwlwifi 0000:03:00.0: Q 10 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576928] iwlwifi 0000:03:00.0: Q 11 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.576983] iwlwifi 0000:03:00.0: Q 12 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577038] iwlwifi 0000:03:00.0: Q 13 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577094] iwlwifi 0000:03:00.0: Q 14 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577149] iwlwifi 0000:03:00.0: Q 15 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577204] iwlwifi 0000:03:00.0: Q 16 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577261] iwlwifi 0000:03:00.0: Q 17 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577317] iwlwifi 0000:03:00.0: Q 18 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.577372] iwlwifi 0000:03:00.0: Q 19 is inactive and mapped to fifo 0 ra_tid 0x0000 [0,0] [ 19.628329] cfg80211: Calling CRDA to update world regulatory domain [ 19.632242] cfg80211: World regulatory domain updated: [ 19.632245] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) [ 19.632247] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [ 19.632249] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [ 19.632250] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [ 19.632252] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [ 19.632253] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [ 23.041735] wlan0: authenticate with 58:6d:8f:c3:47:2e [ 23.068235] wlan0: send auth to 58:6d:8f:c3:47:2e (try 1/3) [ 23.081353] wlan0: authenticated [ 23.082190] wlan0: associate with 58:6d:8f:c3:47:2e (try 1/3) [ 23.085720] wlan0: RX AssocResp from 58:6d:8f:c3:47:2e (capab=0x411 status=0 aid=6) [ 23.091628] wlan0: associated This does not always happen, it's kind of random. I think it happens more frequently in places with a lot of wifi networks available. I'll try with older firmwares as suggested and let you know. I can provide more info if you need. TIA Mariano -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
