bisecting fixing commit since cbfa1702aaf69b2311ea1b35e04f113c48368c67 building syzkaller on ff4a3345a1b2a40ff1b8b983153d0b1fcc72f1c5 testing commit cbfa1702aaf69b2311ea1b35e04f113c48368c67 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 54021c00ceb595a1cd6a932172081b2d5b12756c342d67ce0e6376e55fd471a3 all runs: crashed: possible deadlock in perf_event_ctx_lock_nested testing current HEAD 8ea4f73cfa7e0555dc03aedde52db54a6587ab43 testing commit 8ea4f73cfa7e0555dc03aedde52db54a6587ab43 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: bec2d90ea61e9a7651c0a2832bbe5c35ae6ae0a6d5063c0689ce84af93146692 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 27m6.591126249s (build: 20m11.828583466s, test: 6m23.367670491s) the crash still happens on HEAD commit msg: Linux 4.14.247 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout