Bin Liu <b-liu@xxxxxx> writes: > On Fri, Jan 18, 2019 at 08:15:02PM +0000, Måns Rullgård wrote: >> Bin Liu <b-liu@xxxxxx> writes: >> >> > On Mon, Dec 17, 2018 at 09:36:17PM +0000, Måns Rullgård wrote: >> >> Bin Liu <b-liu@xxxxxx> writes: >> >> >> >> > On Mon, Dec 17, 2018 at 07:16:08PM +0000, Måns Rullgård wrote: >> >> >> Bin Liu <b-liu@xxxxxx> writes: >> >> >> >> >> >> > Hi, >> >> >> > >> >> >> > On Mon, Dec 17, 2018 at 03:13:12PM +0000, Måns Rullgård wrote: >> >> >> >> I have a strange problem with the musb driver in host mode on AM3358 >> >> >> >> (beaglebone) hardware. If I connect a multi-port serial adapter and > > Is this on beaglebone or beagleboneblack? We've seen it with Beaglebone Enhanced [1] and BeagleCore [2] based devices. Both are based on the AM3358 and mostly compatible with the Beaglebone Black. [1] https://elinux.org/SanCloud_BeagleBoneEnhanced [2] http://beaglecore.com/products/bcm1str.html >> >> >> >> open two or more of the ttys, then unplug the device, an interrupt storm >> >> >> >> ensues that makes the system completely unresponsive until the watchdog >> >> >> >> resets it. Enabling some debug messages, I get this repeated endlessly: >> >> >> >> >> >> >> >> musb-hdrc musb-hdrc.1: usbintr (0) epintr(1c0000) >> >> >> >> musb-hdrc musb-hdrc.1: end 2 RX proto error >> >> >> >> musb-hdrc musb-hdrc.1: ... next ep2 RX urb 72aabc13 >> >> >> >> musb-hdrc musb-hdrc.1: <-- hw2 urb 72aabc13 spd3 dev4 ep3in h_addr02 h_port00 bytes 4096 >> >> >> >> musb-hdrc musb-hdrc.1: RXCSR2 := 2020 >> >> >> >> musb-hdrc musb-hdrc.1: end 3 RX proto error >> >> >> >> musb-hdrc musb-hdrc.1: ... next ep3 RX urb 94c2cc43 >> >> >> >> musb-hdrc musb-hdrc.1: <-- hw3 urb 94c2cc43 spd3 dev4 ep2in h_addr02 h_port00 bytes 4096 >> >> >> >> musb-hdrc musb-hdrc.1: RXCSR3 := 2020 >> >> >> >> musb-hdrc musb-hdrc.1: end 4 RX proto error >> >> >> >> musb-hdrc musb-hdrc.1: ... next ep4 RX urb cbdc39c6 >> >> >> >> musb-hdrc musb-hdrc.1: <-- hw4 urb cbdc39c6 spd3 dev4 ep5in h_addr02 h_port00 bytes 4096 >> >> >> >> musb-hdrc musb-hdrc.1: RXCSR4 := 2020 >> >> >> >> >> >> >> >> This happens with both a two-port FTDI serial adapter and a Simcom GSM >> >> >> >> modem (Qualcomm based) using the "option" driver. In both cases, the >> >> >> >> problem occurs only if two or more of the ttys are opened when the >> >> >> >> device is unplugged. >> >> >> > >> >> >> > Please help me to understand the test case so that I can try to >> >> >> > replicate the issue - if I connect a multi-port FTDI adapter, use cat >> >> >> > command to open more than one port then unplug the adapter, I should >> >> >> > see the flooding debug messages? >> >> >> >> >> >> Yes, that's what I'm seeing. Obviously, you have to first enable those >> >> >> debug messages. Otherwise it just stops dead in its tracks. >> >> >> >> >> >> I forgot to mention, I also tried making the interrupt handler threaded. >> >> >> This allows the system to remain slightly responsive, but it never >> >> >> recovers. >> >> >> >> >> >> > On which kernel version do you see the problem? >> >> >> >> >> >> This was on 4.19.9. I don't see any later commits that look related, >> >> >> but I can try some other tree if you suggest one. >> >> > >> >> > This should be fine. The driver was barely touched recently. >> >> > I have only a few days left for 2018, let me try to reproduce it first >> >> > after I am back in Jan. >> >> >> >> No problem. I suspect most of us will have some time off during the >> >> holidays. >> >> >> >> If it helps, we first noticed this with a 4.9 (stable) kernel, so it's >> >> not a recent regression. >> > >> > When I tried to reproduce the issue today, something weird happened, the >> > v4.19.9 kernel I compiled doesn't bring usb1 port on my BBB to host >> > mode, otg state was stuck in a_idle, DevCtl register is 0x81. The latest > > I fixed the the bug which was in the am335x phy driver last week, > >> > v5.0-rc1 and somewhere in v4.16 do not have such problem. I tried git >> > bisect, but it was screwed up somewhere need to start over. I will find >> > some time for this issue. >> > >> > By the way, I don't see the interrupt storm issue with v5.0-rc1 on my >> > BBB, when unplugged the FTDI 4-port device, the 'proto error' message >> > only shows once for each port opened, then MUSB_DISCONNECT interrupt >> > (0x20) happened and everything was torn down. >> >> I tested this with v5.0-rc2. Now the badness doesn't happen every time, >> but two or three attempts is still enough to reproduce it. Also, when >> it does happen, the system no longer freezes completely. It is now >> possible to interrupt the process with the tty open, at which point the >> kernel prints these messages: >> >> ftdi_sio ttyUSB0: failed to get modem status: -71 >> ftdi_sio ttyUSB0: error from flowcontrol urb >> >> Meanwhile, about 10k interrupts per second have been recorded. The USB >> device is still reported as connected, and the port remains unusable. > > but I still cannot see the interrupt storm problem in v4.19.9. > Did you build the kernel with omap2plus_defconfig without any other > changes? No, we use a configuration suitable for our devices. It shouldn't differ in any way that matters though. -- Måns Rullgård
