Bug 88951

Summary:	rtl8192ce scan doesn't find any APs
Product:	Drivers	Reporter:	Catalin Iacob (iacobcatalin)
Component:	network-wireless	Assignee:	drivers_network-wireless (drivers_network-wireless)
Status:	RESOLVED CODE_FIX
Severity:	high	CC:	iacobcatalin, jdelvare, Larry.Finger, markus.boehme, szg00000, timo
Priority:	P1
Hardware:	x86-64
OS:	Linux
Kernel Version:	3.18-rc5	Subsystem:
Regression:	Yes	Bisected commit-id:
Attachments:	Patch 1 of 3 Patch 2 of 3 Patch 3 of 3

Description Catalin Iacob 2014-11-26 19:54:09 UTC

Since the 3.18 merge window my wireless card cannot find any access
point (tested with both NetworkManager and sudo /usr/sbin/iw dev
wlp2s0 scan). More precisely, in 3.18-rc1 I got the oops described at
http://marc.info/?l=linux-wireless&m=141324391807122&w=2. Sometime
after rc1 Larry fixed this but when I tested again I found that scan
doesn't work (tested 3.18-rc3 and just now 3.18-rc5).

According to lspci -nn my hardware is:
02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd.
RTL8188CE 802.11b/g/n WiFi Adapter [10ec:8176] (rev 01)

Comment 1 Larry Finger 2014-11-27 18:40:14 UTC

Created attachment 158911 [details]
Patch 1 of 3

Comment 2 Larry Finger 2014-11-27 18:40:45 UTC

Created attachment 158921 [details]
Patch 2 of 3

Comment 3 Larry Finger 2014-11-27 18:43:24 UTC

Created attachment 158931 [details]
Patch 3 of 3

It took a long time to find these problems. Please test to see if these fix your problem.

It may be too late to get these patches in 3.18; however, they are small enough that they should be applicable to stable, and thus make it into 3.18.1 or 3.18.2.

Comment 4 Catalin Iacob 2014-11-27 20:04:22 UTC

I've tested the patches on top of Linus' current tree (3.18-rc6 plus some patches) and wireless works again.

Thanks a lot for your effort.

I'd say send them to John as soon as possible, maybe they still make 3.18. There shouldn't be a problem with accepting them, they do fix a regression that makes some hardware unusable.

Comment 5 Timo Rothenpieler 2014-12-13 13:22:44 UTC

I'm also affected by this, with the current 3.18 release kernel.
Applying the 3 patches solves the issue for me. Is there any chance of this getting fixed in the next release of 3.18?

Comment 6 Larry Finger 2014-12-13 14:44:15 UTC

Those patches were added to mainline yesterday. I found the problems too late for them to be added to 3.18, thus they are in 3.18-git, which is transitional to 3.19. Now that they are in mainline, I can request that they be backported to 3.18. Accordingly, I have sent E-mail to the maintainer of the 3.18.X stable kernel requesting that they be added there. They should be in 3.18.1 or 3.18.2.

Comment 7 Markus Böhme 2015-01-25 15:11:25 UTC

*** Bug 88681 has been marked as a duplicate of this bug. ***

Comment 8 Larry Finger 2016-02-15 17:00:25 UTC

Could someone with appropriate privileges please close this bug with a CODE FIX? This problem was fixed in November 2014 with mainline commits 87141db0848aa, f892914c0313, and 99a82f734aa6.