Re: dvb usb issues since kernel 4.9
From: Mauro Carvalho Chehab <hidden>
Date: 2018-01-26 19:37:59
Also in:
linux-media, lkml
Em Fri, 26 Jan 2018 12:17:37 -0200 Mauro Carvalho Chehab [off-list ref] escreveu:
Hi Alan, Em Mon, 8 Jan 2018 14:15:35 -0500 (EST) Alan Stern [off-list ref] escreveu:quoted
On Mon, 8 Jan 2018, Linus Torvalds wrote:quoted
Can somebody tell which softirq it is that dvb/usb cares about?I don't know about the DVB part. The USB part is a little difficult to analyze, mostly because the bug reports I've seen are mostly from people running non-vanilla kernels.I suspect that the main reason for people not using non-vanilla Kernels is that, among other bugs, the dwc2 upstream driver has serious troubles handling ISOCH traffic. Using Kernel 4.15-rc7 from this git tree: https://git.linuxtv.org/mchehab/experimental.git/log/?h=softirq_fixup (e. g. with the softirq bug partially reverted with Linux patch, and the DWC2 deferred probe fixed) With a PCTV 461e device, with uses em28xx driver + Montage frontend (with is the same used on dvbsky hardware - except for em28xx). This device doesn't support bulk for DVB, just ISOCH. The drivers work fine on x86. Using a test signal at the bit rate of 56698,4 Kbits/s, that's what happens, when capturing less than one second of data: $ dvbv5-zap -c ~/dvb_channel.conf "tv brasil" -l universal -X 100 -m -t2dvbv5-zap -c ~/dvb_channel.conf "tv brasil" -l universal -X 100 -m -t2 Using LNBf UNIVERSAL Universal, Europe Freqs : 10800 to 11800 MHz, LO: 9750 MHz Freqs : 11600 to 12700 MHz, LO: 10600 MHz using demux 'dvb0.demux0' reading channels from file '/home/mchehab/dvb_channel.conf' tuning to 11468000 Hz (0x00) Signal= -33.90dBm Lock (0x1f) Signal= -33.90dBm C/N= 30.28dB postBER= 2.33x10^-6 dvb_dev_set_bufsize: buffer set to 6160384 dvb_set_pesfilter to 0x2000 354.08s: Starting capture 354.73s: only read 59220 bytes 354.73s: Stopping capture [ 354.000827] dwc2 3f980000.usb: DWC OTG HCD EP DISABLE: bEndpointAddress=0x84, ep->hcpriv=116f41b2 [ 354.000859] dwc2 3f980000.usb: DWC OTG HCD EP RESET: bEndpointAddress=0x84 [ 354.010744] dwc2 3f980000.usb: --Host Channel 5 Interrupt: Frame Overrun-- ... (hundreds of thousands of Frame Overrun messages) [ 354.660857] dwc2 3f980000.usb: --Host Channel 5 Interrupt: Frame Overrun-- [ 354.660935] dwc2 3f980000.usb: DWC OTG HCD URB Dequeue [ 354.660959] dwc2 3f980000.usb: Called usb_hcd_giveback_urb() [ 354.660966] dwc2 3f980000.usb: urb->status = 0 [ 354.660992] dwc2 3f980000.usb: DWC OTG HCD URB Dequeue [ 354.661001] dwc2 3f980000.usb: Called usb_hcd_giveback_urb() [ 354.661008] dwc2 3f980000.usb: urb->status = 0 [ 354.661054] dwc2 3f980000.usb: DWC OTG HCD URB Dequeue [ 354.661065] dwc2 3f980000.usb: Called usb_hcd_giveback_urb() [ 354.661072] dwc2 3f980000.usb: urb->status = 0 [ 354.661107] dwc2 3f980000.usb: DWC OTG HCD URB Dequeue [ 354.661120] dwc2 3f980000.usb: Called usb_hcd_giveback_urb() [ 354.661127] dwc2 3f980000.usb: urb->status = 0 [ 354.661146] dwc2 3f980000.usb: DWC OTG HCD URB Dequeue [ 354.661158] dwc2 3f980000.usb: Called usb_hcd_giveback_urb() [ 354.661165] dwc2 3f980000.usb: urb->status = 0
Btw, Just in case, I also applied all recent pending dwc2 patches I found at linux-usb (even trivial unrelated ones) at: https://git.linuxtv.org/mchehab/experimental.git/log/?h=dwc2_patches No differences. ISOCH is still broken. If anyone wants to see the full logs, it is there: https://pastebin.com/XJYyTwPv Cheers, Mauro