Re: lost connectivity until "wpa_cli reassociate" is issued
On Thu, Jan 7, 2016 at 9:58 AM, Krishna Chaitanya wrote: > We can check pending packets per queue at mac80211, but first > we need some info from driver level. Someone familiar with RTL > should help. > > cat /sys/kernel/debug/ieee80211/phy*/queues > > If you see non-zero packets here (or) if the queue is stopped > that might explain this behavior... Cool. I'll check that next time it happens, thanks! --david -- eGauge Systems LLC, http://egauge.net/, 1.877-EGAUGE1, fax 720.545.9768 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
On Thu, Jan 7, 2016 at 10:17 PM, David Mosberger wrote: > On Thu, Jan 7, 2016 at 9:32 AM, Krishna Chaitanya > wrote: > >> Management frames use a different queue (VO) >> from the logs it looks like a data path issue in driver/FW. >> >> The re-association might be clearing/triggering TX in driver >> solving the issue. > > That sounds plausible to me. Is there an easy way to see the queues? > I haven't tried debugfs yet. We can check pending packets per queue at mac80211, but first we need some info from driver level. Someone familiar with RTL should help. cat /sys/kernel/debug/ieee80211/phy*/queues If you see non-zero packets here (or) if the queue is stopped that might explain this behavior... -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
On Thu, Jan 7, 2016 at 9:32 AM, Krishna Chaitanya wrote: > Management frames use a different queue (VO) > from the logs it looks like a data path issue in driver/FW. > > The re-association might be clearing/triggering TX in driver > solving the issue. That sounds plausible to me. Is there an easy way to see the queues? I haven't tried debugfs yet. --david -- eGauge Systems LLC, http://egauge.net/, 1.877-EGAUGE1, fax 720.545.9768 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
Ben, On Thu, Jan 7, 2016 at 9:33 AM, Ben Greear wrote: > Could be > a power-save issue perhaps. That was our thought, too. Particularly, since if there is steady traffic (at least a ping every 8 seconds), the problem does not appear to occur. However, the rtl8192cu doesn't support power-saving mode and in any case, we made sure it's off: # iw wlan0 get power_save Power save: off > I assume you have sniffed to see if any frames are going out on the air > during the time of trouble? No, I'm not actually sure how I'd do that. The site we see this most frequently with is remote and we don't have any special WiFi packet sniffer. > If correct packets go out on the air and AP doesn't answer, then likely AP > problem. Not likely an AP problem, since we're seeing this with multiple APs of different brands etc. > If pkts don't get on the air, then check to see if they at least get to > the driver. Yeah, that should be easy to do, I suppose. We had rtl8192cu debugging turned on before but at that time it didn't help. > If they don't get to the driver, then probably it is a kernel/stack issue. > > If they get to the driver but not on the air, then NIC and/or it's firmware > and/or the driver is likely the culprit. Thanks for your thoughts! --david -- eGauge Systems LLC, http://egauge.net/, 1.877-EGAUGE1, fax 720.545.9768 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
On 01/07/2016 08:29 AM, David Mosberger wrote: Ben, On Thu, Jan 7, 2016 at 9:24 AM, Ben Greear wrote: On 01/07/2016 08:19 AM, David Mosberger wrote: We are seeing a curious issue where WLAN connectivity sometimes gets stuck until a "wpa_cli reassociate" command is issued. At the WPA level, everything appears to be working fine) (see thread starting at http://lists.infradead.org/pipermail/hostap/2016-January/034454.html). I don't remember seeing you mention the driver and NIC you are using. I think this is likely a driver bug, so please provide that info. Sure, we're using rtl8192cu. I started out suspecting a driver bug as well, but since we're processing management frames during those "stuck" periods just fine (see debug output in http://lists.infradead.org/pipermail/hostap/2016-January/034459.html), I'm not so sure anymore. Like mac80211, we have patched rtl8192cu driver with current bug-fixes already. I have no experience with that chip, but wifi is a tricky beast. Could be a power-save issue perhaps. I assume you have sniffed to see if any frames are going out on the air during the time of trouble? If correct packets go out on the air and AP doesn't answer, then likely AP problem. If pkts don't get on the air, then check to see if they at least get to the driver. If they don't get to the driver, then probably it is a kernel/stack issue. If they get to the driver but not on the air, then NIC and/or it's firmware and/or the driver is likely the culprit. Thanks, Ben --david -- Ben Greear Candela Technologies Inc http://www.candelatech.com -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
On Thu, Jan 7, 2016 at 9:59 PM, David Mosberger wrote: > > Ben, > > On Thu, Jan 7, 2016 at 9:24 AM, Ben Greear wrote: > > On 01/07/2016 08:19 AM, David Mosberger wrote: > >> > >> We are seeing a curious issue where WLAN connectivity sometimes > >> gets stuck until a "wpa_cli reassociate" command is issued. > >> > >> At the WPA level, everything appears to be working fine) > >> (see thread starting at > >> http://lists.infradead.org/pipermail/hostap/2016-January/034454.html). > > > > I don't remember seeing you mention the driver and NIC you are using. > > > > I think this is likely a driver bug, so please provide that info. > > Sure, we're using rtl8192cu. I started out suspecting a driver bug as > well, but since we're processing management frames during those > "stuck" periods just fine (see > debug output in > http://lists.infradead.org/pipermail/hostap/2016-January/034459.html), > I'm not so sure anymore. Like mac80211, we have patched rtl8192cu > driver with current > bug-fixes already. Management frames use a different queue (VO) from the logs it looks like a data path issue in driver/FW. The re-association might be clearing/triggering TX in driver solving the issue. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: lost connectivity until "wpa_cli reassociate" is issued
Ben, On Thu, Jan 7, 2016 at 9:24 AM, Ben Greear wrote: > On 01/07/2016 08:19 AM, David Mosberger wrote: >> >> We are seeing a curious issue where WLAN connectivity sometimes >> gets stuck until a "wpa_cli reassociate" command is issued. >> >> At the WPA level, everything appears to be working fine) >> (see thread starting at >> http://lists.infradead.org/pipermail/hostap/2016-January/034454.html). > > I don't remember seeing you mention the driver and NIC you are using. > > I think this is likely a driver bug, so please provide that info. Sure, we're using rtl8192cu. I started out suspecting a driver bug as well, but since we're processing management frames during those "stuck" periods just fine (see debug output in http://lists.infradead.org/pipermail/hostap/2016-January/034459.html), I'm not so sure anymore. Like mac80211, we have patched rtl8192cu driver with current bug-fixes already. --david -- eGauge Systems LLC, http://egauge.net/, 1.877-EGAUGE1, fax 720.545.9768 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html