In the Linux kernel, the following vulnerability has been resolved: net: usb: aqc111: Do not perform PM inside suspend callback syzbot reports "task hung in rpmresume" This is caused by aqc111suspend calling the PM variant of its writecmd routine. The simplified call trace looks like this: rpmsuspend() usbsuspendboth() - here udev->dev.power.runtimestatus == RPMSUSPENDING aqc111suspend() - called for the usb device interface aqc111write32cmd() usbautopmgetinterface() pmruntimeresumeandget() rpmresume() - here we call rpmresume() on our parent rpmresume() - Here we wait for a status change that will never happen. At this point we block another task which holds rtnllock and locks up the whole networking stack. Fix this by replacing the write_cmd calls with their _nopm variants