bisecting fixing commit since 2762b48e9611529239da2e68cba908dbbec9805f building syzkaller on 63631df1539816bc62c7be40779c5f3e23b23b2f testing commit 2762b48e9611529239da2e68cba908dbbec9805f compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 743d14a450d38ed7b568f7809bdedad364130d497a7232389964206637f3b2b2 run #0: crashed: KASAN: use-after-free Read in perf_output_read run #1: crashed: KASAN: use-after-free Read in perf_output_read run #2: crashed: KASAN: use-after-free Read in perf_output_read run #3: crashed: KASAN: use-after-free Read in perf_output_read run #4: crashed: BUG: soft lockup in __perf_sw_event run #5: crashed: KASAN: use-after-free Read in perf_output_read run #6: crashed: KASAN: use-after-free Read in perf_output_read run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing current HEAD 964f3712e6a7447d9d3203f2be3f6c50e78ea179 testing commit 964f3712e6a7447d9d3203f2be3f6c50e78ea179 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 6b8ce2f46219b24f11624e46f9ece81ed70b17cee5c075719010741cc4a93259 all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 34m29.642174225s (build: 18m32.985477187s, test: 15m18.095834573s) the crash still happens on HEAD commit msg: Linux 4.14.240 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout