Re: urtwn(4) device timeouts with RTL8188CUS

[Josh Grosse]

On Sun, Oct 20, 2013 at 09:12:18AM -0400, I wrote:
> Thanks, but my symptoms are that it works in one platform and not another.
> I'm on my second device, under warranty, as the first was DOA.  

I just tested the server/device combination under Linux, and it functioned
correctly.  This is leaning towards the driver, rather than the hardware. 

Re: urtwn(4) device timeouts with RTL8188CUS

[Josh Grosse]

On Sun, Oct 20, 2013 at 09:14:12PM +1100, Jonathan Gray wrote:
> Perhaps there is a problem with the via usb controllers.
> If you disable ehci via ukc do you still see the problem?

Unfortunately, USB 2.0 is required.  One of my early tests was to disable 
ehci(4) to force uhci(4) use.  It resulted in a "urtwn0: timeout waiting 
for MAC initialization" message and no network connectivity at all.

Thanks for thinking of this.

Re: urtwn(4) device timeouts with RTL8188CUS

[Josh Grosse]

On Sun, Oct 20, 2013 at 02:37:40PM +0200, frantisek holop wrote:
> this rang a bell :]
> just for the record, the usb dongle mentioned kept
> steadily deteriorating until it finally died any moment
> i touched it (which happened a lot if the netbook was
> in my lap) thus leaving my services..  i'd buy
> a different one i guess.

Thanks, but my symptoms are that it works in one platform and not another.
I'm on my second device, under warranty, as the first was DOA.  

Re: urtwn(4) device timeouts with RTL8188CUS

[Josh Grosse]

On Sun, Oct 20, 2013 at 02:32:22PM +0200, Stefan Sperling wrote:
> I have a urtwn that runs quite hot when it exhibits similar problems.
> Pulling it out and letting it cool down for a while usually fixes it.
> Putting it back in immediately usually results in the same symptoms
> right away.

This is my second key from this particular manufacture (EDUP EP-N8508, 
sold by Ariic through Newegg.com).  The first exhibited overheat within
several minutes of insertion and its radio output disabled the local 802.11g 
network for all users.  This second key does not have these DOA sypmtoms.
 
> A shot in the dark idea is that our driver might not be handling power
> management in a way that the vendor envisioned, so the device runs
> too hot and stops working properly.
 
That's a reasonable assumption, even though with two of them my experience
has been a little different. 

Re: urtwn(4) device timeouts with RTL8188CUS

[frantisek holop]

hmm, on Sat, Oct 19, 2013 at 03:13:35PM -0400, josh said that
> I have a USB 802.11n capable dongle that works fine in a netbook[3] but not 
> in a server[2], which is where it was intended.  The sypmtom is a cessation 
> of packet traffic followed by device timeout as described in urtwn(4).  
> A similar problem was mentioned last year[1] on misc@, though the specific 
> Realtek chipset involved was not posted.
> 
> [1] http://marc.info/?t=13466680111&r=1&w=2

this rang a bell :]
just for the record, the usb dongle mentioned kept
steadily deteriorating until it finally died any moment
i touched it (which happened a lot if the netbook was
in my lap) thus leaving my services..  i'd buy
a different one i guess.

-f
-- 
i'm feeling rather blonde today.

Re: urtwn(4) device timeouts with RTL8188CUS

[Stefan Sperling]

On Sat, Oct 19, 2013 at 03:13:35PM -0400, josh wrote:
> I have a USB 802.11n capable dongle that works fine in a netbook[3] but not 
> in a server[2], which is where it was intended.  The sypmtom is a cessation 
> of packet traffic followed by device timeout as described in urtwn(4).  
> A similar problem was mentioned last year[1] on misc@, though the specific 
> Realtek chipset involved was not posted.
> 
> I built a kernel with USB_DEBUG which enables URTWN_DEBUG, and while running 
> with that test kernel I could not replicate the problem.  From that test, I 
> understand that timing or a race condition are likely areas of research. It
> aligns also with the slower system [3] not being able to replicate either.
> 
> I could use some help as I am unsure how to investigate further.  I tried
> doubling the sc_tx_timer in if_urtwn.c from 5 to 10, with no effect, but 
> that was just a stab in the dark.  Any suggestions for futher tests, or 
> a whack with a cluestick would be welcome.

I have a urtwn that runs quite hot when it exhibits similar problems.
Pulling it out and letting it cool down for a while usually fixes it.
Putting it back in immediately usually results in the same symptoms
right away.

A shot in the dark idea is that our driver might not be handling power
management in a way that the vendor envisioned, so the device runs
too hot and stops working properly.

urtwn(4) device timeouts with RTL8188CUS

[josh]

I have a USB 802.11n capable dongle that works fine in a netbook[3] but not 
in a server[2], which is where it was intended.  The sypmtom is a cessation 
of packet traffic followed by device timeout as described in urtwn(4).  
A similar problem was mentioned last year[1] on misc@, though the specific 
Realtek chipset involved was not posted.

I built a kernel with USB_DEBUG which enables URTWN_DEBUG, and while running 
with that test kernel I could not replicate the problem.  From that test, I 
understand that timing or a race condition are likely areas of research. It
aligns also with the slower system [3] not being able to replicate either.

I could use some help as I am unsure how to investigate further.  I tried
doubling the sc_tx_timer in if_urtwn.c from 5 to 10, with no effect, but 
that was just a stab in the dark.  Any suggestions for futher tests, or 
a whack with a cluestick would be welcome.

Thanks!

-Josh Grosse-

[1] http://marc.info/?t=13466680111&r=1&w=2

[2] System that displays the timeout problem:

OpenBSD 5.4-current (GENERIC.MP) #82: Tue Oct 15 01:02:02 MDT 2013
dera...@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC.MP
cpu0: Intel(R) Core(TM)2 Duo CPU E7200 @ 2.53GHz ("GenuineIntel" 686-class) 
1.60 GHz
cpu0: 
FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,LONG,SSE3,DTES64,MWAIT,DS-CPL,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,LAHF,PERF
real mem  = 1072951296 (1023MB)
avail mem = 1043644416 (995MB)
mainbus0 at root
bios0 at mainbus0: AT/286+ BIOS, date 02/26/08, BIOS32 rev. 0 @ 0xf0010, SMBIOS 
rev. 2.4 @ 0xfb450 (24 entries)
bios0: vendor American Megatrends Inc. version "P1.90" date 02/26/2008
acpi0 at bios0: rev 0
acpi0: sleep states S0 S1 S4 S5
acpi0: tables DSDT FACP APIC MCFG OEMB
acpi0: wakeup devices PCI0(S4) USB1(S4) USB2(S4) USB3(S4) USB4(S4) EHCI(S4) 
PS2K(S4) PS2M(S4) UAR1(S4) SLAN(S4) P0PA(S4) SLPB(S4) HDAC(S5)
acpitimer0 at acpi0: 3579545 Hz, 24 bits
acpimadt0 at acpi0 addr 0xfee0: PC-AT compat
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: apic clock running at 266MHz
cpu0: mwait min=64, max=64, C-substates=0.2.2.2.2, IBE
cpu1 at mainbus0: apid 1 (application processor)
cpu1: Intel(R) Core(TM)2 Duo CPU E7200 @ 2.53GHz ("GenuineIntel" 686-class) 
2.53 GHz
cpu1: 
FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,LONG,SSE3,DTES64,MWAIT,DS-CPL,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,LAHF,PERF
ioapic0 at mainbus0: apid 2 pa 0xfec0, version 3, 24 pins
ioapic1 at mainbus0: apid 3 pa 0xfecc, version 3, 24 pins
acpimcfg0 at acpi0 addr 0xe000, bus 0-255
acpiprt0 at acpi0: bus 0 (PCI0)
acpiprt1 at acpi0: bus -1 (P0P9)
acpiprt2 at acpi0: bus 3 (P0PA)
acpiprt3 at acpi0: bus 2 (NBPG)
acpiprt4 at acpi0: bus 128 (PCI1)
acpicpu0 at acpi0
acpicpu1 at acpi0
acpibtn0 at acpi0: SLPB
acpibtn1 at acpi0: PWRB
bios0: ROM list: 0xc/0xec00
cpu0: Enhanced SpeedStep disabled by BIOS
pci0 at mainbus0 bus 0: configuration mode 1 (bios)
pchb0 at pci0 dev 0 function 0 "VIA PT894 Host" rev 0x00
viaagp0 at pchb0: v3
agp0 at viaagp0: aperture at 0xf800, size 0xf00
pchb1 at pci0 dev 0 function 1 "VIA PT894 Host" rev 0x00
pchb2 at pci0 dev 0 function 2 "VIA PT894 Host" rev 0x00
pchb3 at pci0 dev 0 function 3 "VIA PT890 Host" rev 0x00
pchb4 at pci0 dev 0 function 4 "VIA PT894 Host" rev 0x00
"VIA PT894 IOAPIC" rev 0x00 at pci0 dev 0 function 5 not configured
pchb5 at pci0 dev 0 function 7 "VIA PT894 Host" rev 0x00
ppb0 at pci0 dev 1 function 0 "VIA VT8377 AGP" rev 0x00
pci1 at ppb0 bus 1
vga1 at pci1 dev 0 function 0 "NVIDIA GeForce 7600 GT" rev 0xa2
wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation)
wsdisplay0: screen 1-5 added (80x25, vt100 emulation)
ppb1 at pci0 dev 2 function 0 vendor "VIA", unknown product 0xa208 rev 0x00: 
apic 3 int 3
pci2 at ppb1 bus 2
pciide0 at pci0 dev 15 function 0 "VIA VT8237S SATA" rev 0x00: DMA
pciide0: using apic 2 int 21 for native-PCI interrupt
pciide1 at pci0 dev 15 function 1 "VIA VT82C571 IDE" rev 0x07: DMA, channel 0 
configured to compatibility, channel 1 configured to compatibility
wd0 at pciide1 channel 0 drive 0: 
wd0: 16-sector PIO, LBA48, 76319MB, 156301488 sectors
wd1 at pciide1 channel 0 drive 1: 
wd1: 16-sector PIO, LBA48, 715404MB, 1465149168 sectors
wd0(pciide1:0:0): using PIO mode 4, DMA mode 2
wd1(pciide1:0:1): using PIO mode 4, DMA mode 2
wd2 at pciide1 channel 1 drive 0: 
wd2: 16-sector PIO, LBA48, 78533MB, 160836480 sectors
wd3 at pciide1 channel 1 drive 1: 
wd3: 8-sector PIO, LBA, 38172MB, 78177792 sectors
wd2(pciide1:1:0): using PIO mode 4, DMA mode 2
wd3(pciide1:1:1): using PIO mode 4, DMA mode 2
uhci0 at pci0 dev 16 function 0 "VIA VT83C572 USB" rev 0xb0: apic 2 int 20
uhci1 at pci0 dev 16 function 1 "VIA VT83C572 USB" rev 0xb0: apic 2 int 22
uhci2 at pci0 dev 16 function 2 "VIA VT83C572 USB" rev 0xb0: apic 2 int 21
uhci3 at pci0 dev 16 function 3 "VIA VT83C572 USB" rev