On 03/23/20 11:54, Alan Stern wrote: > On Mon, 23 Mar 2020, Oliver Neukum wrote: > > > Am Montag, den 23.03.2020, 14:38 +0000 schrieb Qais Yousef: > > > Hi > > > > > > I've hit the following lockdep warning when I trigger hibernate on arm64 > > > platform (Juno-r2) > > > > > > > > > echo suspend > /sys/power/disk > > > echo disk > /sys/power/state > > > > > > I only had a usb flash drive attached to it. Let me know if you need more info. > > > > Hi, > > > > that is not a lockdep issue, but the hub driver is not properly killing > > its URB presumably. Yet, the driver looks correct to me. Please use > > the additional patch and activate dynamic debugging for usbcore. > > Was the USB flash drive being used as a swap device for holding the > hibernation image? That's not likely to work very well. At least, I > doubt that it has been tested very much. > > This diagnostic was suggested by the runtime PM error that occurred > when the system was trying to store the hibernation image. That's > probably when the hub driver's URB got restarted. Yes, sadly it's the only source of storage I have on that device. When I ran the test I had swapoff, as you can see in the snippet below. When swap is on I do hibernate and wakeup successfully. At least that's what appears to be happening to me. I get a similar splat regardless of swap is on or off. [ 327.154849] usb usb2: runtime PM trying to activate child device usb2 but parent (7ffb0000.ohci) is not active [ 327.290355] PM: Cannot find swap device, try swapon -a [ 327.295533] PM: Cannot get swap writer [ 327.480758] OOM killer enabled. [ 327.483939] Restarting tasks ... [ 327.484229] ------------[ cut here ]------------ [ 327.484664] done. [ 327.487743] URB 000000000c121c1c submitted while active [ 327.499622] WARNING: CPU: 1 PID: 296 at drivers/usb/core/urb.c:363 usb_submit_urb+0x3f0/0x520 Thanks -- Qais Yousef
