Den fre. 26. feb. 2021 kl. 15.14 skrev Bruno Thomsen <bruno.thomsen@xxxxxxxxx>: > > Den tor. 25. feb. 2021 kl. 10.57 skrev Oliver Neukum <oneukum@xxxxxxxx>: > > > > Am Mittwoch, den 24.02.2021, 16:21 +0100 schrieb Bruno Thomsen: > > > > Hi, > > > > > No, this is not a regression from 5.10. It seems that many attempts to > > > fix cdc-acm in the 5.x kernel series have failed to fix the root cause of > > > these oops. I have not seen this on 4.14 and 4.19, but I have observed > > > it on at least 5.3 and newer kernels in slight variations. > > > I guess this is because cdc-acm is very common in the embedded > > > ARM world and rarely used on servers or laptops. Combined with > > > ARM devices still commonly use 4.x LTS kernels. Not sure if > > > hardening options on the kernel has increased change of reproducing > > > oops. > > > > OK, so this is not an additional problem. > > According to your logs, an URB that should have been killed wasn't. > > Thanks for looking into this bug rapport. > > > > I am ready to test new patches and will continue to report oops > > > > Could you test the attached patches? > > Yes, I am already running tests on the patches. > I have not seen any oops yet and it seems the USB cdc-acm driver is still > working as intended. > > The only notable trace I have seen is this new error from the cdc-acm driver > but everything kept on working. > kernel: cdc_acm 1-1.1:1.7: acm_start_wb - usb_submit_urb(write bulk) failed: -19 > > Other then that I see this common error (should probably be a warning) during > device enumeration: > kernel: cdc_acm 1-1.2:1.0: failed to set dtr/rts > > I will post an update next week when the patches have survived some > more runtime. Tested-by: Bruno Thomsen <bruno.thomsen@xxxxxxxxx> I have not observed any oops with patches applied. Patches have seen more than 10 weeks of runtime testing across multiple devices. /Bruno
