On 09/15/2017 05:10 AM, Zwindl wrote:

quoted

-------- Original Message --------
Subject: Re: RTL8192EE PCIe Wireless Network Adapter crashed with linux-4.13
Local Time: 14 September 2017 6:05 PM
UTC Time: 14 September 2017 18:05
From: Larry.Finger@lwfinger.net
To: Zwindl <redacted>, linux-wireless@vger.kernel.org 
[off-list ref]
chaoming_li@realsil.com.cn [off-list ref], kvalo@codeaurora.org 
[off-list ref], pkshih@realtek.com [off-list ref], 
johannes.berg@intel.com [off-list ref], gregkh@linuxfoundation.org 
[off-list ref], netdev@vger.kernel.org [off-list ref], 
linux-kernel@vger.kernel.org [off-list ref]

On 09/14/2017 08:30 AM, Zwindl wrote:

quoted

Dear developers:
I"m using Arch Linux with testing enabled, the current kernel version and
details are
`Linux zwindl 4.13.2-1-ARCH #1 SMP PREEMPT Thu Sep 14 02:57:34 UTC 2017 x86_64
GNU/Linux`.
The wireless card can"t work properly from the kernel 4.13. Here"s the log(in
attachment) when NetworkManager trying to connect my wifi which is named as
"TP", my mac addr hided as xx:xx:xx:xx:xx.
What should I provide to help to debug?
ZWindL.

The BUG-ON arises in __intel_map_single() due to dir (for direction of DMA)
equal to DMA_NONE (3). When rtl8192ee calls pci_map_single(), it uses
PCI_DMA_TODEVICE (1). I followed the calling sequence through the entire chain,
and none of the routines made any changes to "dir", other that changing the type
from int to enum dma_data_direction. That would not have changed a 1 to a 3.

I built a 4.13.2 system. The problem does not happen here. At this point, the
system has been up for about two hours. I did discover a small memory leak
associated with firmware loading, but that should not have caused the problem.
Nonetheless, I will be sending a patch to fix that problem.

I will continue testing, although I doubt that the problem will happen here.

How long had your system been up when the problem occurred? Your dmesg fragment
did not show any times. What kernels have you tried besides 4.13.2?

Larry

Oh, sorry, the original log is from `journalctl`.
Here's the `dmesg` prints(error.txt). I can't determine which part is related, 
so I paste all of it. I've tried 4.12.X(no issue), 4.13.1(issue), 4.13.2(issue).
ZWindL

The output of dmesg is a lot more instructive than that of journalctl. I now 
know exactly the location that triggered the WARNING. I still do not understand 
it. In fact, it is likely a regression in kernel 4.13 that does not affect my 
Toshiba laptop, nor a Lenovo machine I have, but does affect your Lenovo laptop.

Is it possible for you to install the mainline source from vger.kernel.org using 
git and bisect the issue? It will take quite a bit of time, but it is likely the 
only way to find the offending change. If you are willing to try this, I will 
send you reasonably complete instructions.

By the way, it is usually better to load the dmesg output into a pastebin site 
and post the link. Sending the entire file to a list makes a lot of people 
receive a lot of data for which they have no interest.

Larry