4.4-stable review patch. If anyone has any objections, please let me know.
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This reverts commit 3fdd34643ffc378b5924941fad40352c04610294 which was upstream commit 4ec7cece87b3ed21ffcd407c62fb2f151a366bc1.
From Dietmar May's report on the stable mailing list
(https://www.spinics.net/lists/stable/msg272201.html):
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/kernel/git/stable/linux.git/commit/?h=linux-4.9.y&id=afeeecc764436f31d4447575bb9007732333818c. 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.
Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/ti/wlcore/cmd.c | 6 ------ 1 file changed, 6 deletions(-)
--- a/drivers/net/wireless/ti/wlcore/cmd.c +++ b/drivers/net/wireless/ti/wlcore/cmd.c @@ -35,7 +35,6 @@ #include "wl12xx_80211.h" #include "cmd.h" #include "event.h" -#include "ps.h" #include "tx.h" #include "hw_ops.h"
@@ -192,10 +191,6 @@ int wlcore_cmd_wait_for_event_or_timeout
timeout_time = jiffies + msecs_to_jiffies(WL1271_EVENT_TIMEOUT);
- ret = wl1271_ps_elp_wakeup(wl); - if (ret < 0) - return ret; - do { if (time_after(jiffies, timeout_time)) { wl1271_debug(DEBUG_CMD, "timeout waiting for event %d", @@ -227,7 +222,6 @@ int wlcore_cmd_wait_for_event_or_timeout } while (!event);
out: - wl1271_ps_elp_sleep(wl); kfree(events_vector); return ret; }