From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: wlcore update breaks on 4.9 and 4.4 kernel branches To: Sasha Levin Cc: stable@vger.kernel.org, linux-wireless@vger.kernel.org References: <43ee432a-c6ab-e23c-616c-b626a5fb4637@intellastar.com> <20181202150813.GG221015@sasha-vm> From: Dietmar May Message-ID: <72dcddb8-a44a-d50c-bae6-c51180e53cc8@intellastar.com> Date: Tue, 11 Dec 2018 15:29:31 -0500 MIME-Version: 1.0 In-Reply-To: <20181202150813.GG221015@sasha-vm> Content-Type: multipart/alternative; boundary="------------4E3325C24D7031C981F94221" Content-Language: en-US List-ID: This is a multi-part message in MIME format. --------------4E3325C24D7031C981F94221 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: quoted-printable Sasha, I've verified that 4.9.143 no longer exhibits this problem. The revert hasn't shown up in 4.4 yet; but I'll verify once merged there. Thanks, Dietmar ------------------------------------------------------------------------ On 12/2/18 10:08 AM, Sasha Levin wrote: > On Thu, Nov 29, 2018 at 05:56:31PM -0500, Dietmar May wrote: >> I've run into some problems which appear due to (a) recent patch(es)=20 >> on the wlcore wifi driver. >> >> 4.4.160 - commit 3fdd34643ffc378b5924941fad40352c04610294 >> 4.9.131 - commit afeeecc764436f31d4447575bb9007732333818c >> >> Earlier versions (4.9.130 and 4.4.159 - tested back to 4.4.49) do not=20 >> exhibit this problem. It is still present in 4.9.141. >> >> master as of 4.20.0-rc4 does not exhibit this problem. >> >> Basically, during client association when in AP mode (running=20 >> hostapd), handshake may or may not complete following a noticeable=20 >> delay. If successful, then the driver fails consistently in=20 >> warn_slowpath_null during disassociation. If unsuccessful, the wifi=20 >> client attempts multiple times, sometimes failing repeatedly. I've=20 >> had clients unable to connect for 3-5 minutes during testing, with=20 >> the syslog filled with dozens of backtraces. syslog details are below. >> >> I'm working on an embedded device with a TI 3352 ARM processor and a=20 >> murata wl1271 module in sdio mode. We're running a fully patched=20 >> ubuntu 18.04 ARM build, with a kernel built from kernel.org's=20 >> stable/linux repo=20 >> .=20 >> Relevant parts of the kernel config are included below. >> >> The commit message states: >> >>> /I've only seen this few times with the runtime PM patches enabled=20 >>> so this one is probably not needed before that. This seems to work=20 >>> currently based on the current PM implementation timer. Let's apply=20 >>> this separately though in case others are hitting this issue./ >> We're not doing anything explicit with power management. The device=20 >> is an IoT edge gateway with battery backup, normally running on wall=20 >> power. The battery is currently used solely to shut down the system=20 >> cleanly to avoid filesystem corruption. >> >> The device tree is configured to keep power in suspend; but the=20 >> device should never suspend, so in our case, there is no need to call=20 >> wl1271_ps_elp_wakeup() or wl1271_ps_elp_sleep(), as occurs in the patch. > > Given that this patch went in through AUTOSEL, I've queued up a revert > of it (sorry for the trouble!). > > I'll link this mail in the revert message. If anyone feels that this > patch should be in any of the LTS trees then either reply to this thread > or start a new one on stable@vger.kernel.org. > > --=20 > Thanks, > Sasha --=20 This email and any information disclosed in connection herewith, whether=20 written or oral, is the property of Intellastar LLC, and is intended only= =20 for the person or entity to which it is addressed. This email may contain= =20 information that is privileged confidential or otherwise protected from=20 disclosure. Distributing or copying any information contained in this email= =20 to anyone other than the intended recipient is strictly prohibited.=C2=A0 --------------4E3325C24D7031C981F94221 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

Sasha,

I've verified that 4.9.143 no longer exhibits this problem.

The revert hasn't shown up in 4.4 yet; but I'll verify once merged there.

Thanks,
Dietmar
On 12/2/18 10:08 AM, Sasha Levin wrote:=
On Thu, Nov 29, 2018 at 05:56:31PM -0500, Dietmar May wrote:
I've run into some problems which appear due to (a) recent patch(es) on the wlcore wifi driver.

4.4.160 - commit 3fdd34643ffc378b5924941fad40352c04610294
4.9.131 - commit afeeecc764436f31d4447575bb9007732333818c

Earlier versions (4.9.130 and 4.4.159 - tested back to 4.4.49) do not exhibit this problem. It is still present in 4.9.141.

master as of 4.20.0-rc4 does not exhibit this problem.

Basically, during client association when in AP mode (running hostapd), handshake may or may not complete following a noticeable delay. If successful, then the driver fails consistently in warn_slowpath_null during disassociation. If unsuccessful, the wifi client attempts multiple times, sometimes failing repeatedly. I've had clients unable to connect for 3-5 minutes during testing, with the syslog filled with dozens of backtraces. syslog details are below.

I'm working on an embedded device with a TI 3352 ARM processor and a murata wl1271 module in sdio mode. We're running a fully patched ubuntu 18.04 ARM build, with a kernel built from kernel.org's stable/linux repo <https://git.kernel.org/pub/scm/linux/k= ernel/git/stable/linux.git/commit/?h=3Dlinux-4.9.y&id=3Dafeeecc764436f3= 1d4447575bb9007732333818c>. Relevant parts of the kernel config are included below.

The commit message states:

/I've only seen this few times with the runtime PM patches enabled so this one is probably not needed before that. This seems to work currently based on the current PM implementation timer. Let's apply this separately though in case others are hitting this issue./
We're not doing anything explicit with power management. The device is an IoT edge gateway with battery backup, normally running on wall power. The battery is currently used solely to shut down the system cleanly to avoid filesystem corruption.

The device tree is configured to keep power in suspend; but the device should never suspend, so in our case, there is no need to call wl1271_ps_elp_wakeup() or wl1271_ps_elp_sleep(), as occurs in the patch.

Given that this patch went in through AUTOSEL, I've queued up a revert
of it (sorry for the trouble!).

I'll link this mail in the revert message. If anyone feels that this
patch should be in any of the LTS trees then either reply to this thread
or start a new one on stable@vger.kernel.org.

--
Thanks,
Sasha

This email and any information disclosed in connection herewith, whether wr= itten or oral, is the property of Intellastar LLC, and is intended only for= the person or entity to which it is addressed. This email may contain info= rmation that is privileged confidential or otherwise protected from disclos= ure. Distributing or copying any information contained in this email to any= one other than the intended recipient is strictly prohibited.=C2=A0 --------------4E3325C24D7031C981F94221--