bisecting fixing commit since cbfa1702aaf69b2311ea1b35e04f113c48368c67 building syzkaller on 062c9832a6cdb39bf38ad7a6dad51300a2e9a734 testing commit cbfa1702aaf69b2311ea1b35e04f113c48368c67 with gcc (GCC) 8.4.1 20210217 kernel signature: 98e9dfbcb715f503620ae0fb8b9c6a40557c9fbe6439f3288925c1264ed59220 run #0: crashed: general protection fault 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: KASAN: use-after-free Read in perf_output_read run #5: crashed: KASAN: use-after-free Read in perf_output_read run #6: crashed: BUG: soft lockup in __perf_sw_event run #7: crashed: KASAN: use-after-free Read in perf_output_read run #8: crashed: KASAN: use-after-free Read in perf_output_read run #9: crashed: KASAN: use-after-free Read in perf_output_read run #10: crashed: KASAN: use-after-free Read in perf_output_read run #11: crashed: KASAN: use-after-free Read in perf_output_read run #12: crashed: KASAN: use-after-free Read in perf_output_read run #13: crashed: KASAN: use-after-free Read in perf_output_read run #14: crashed: KASAN: use-after-free Read in perf_output_read run #15: crashed: BUG: soft lockup in __perf_sw_event run #16: crashed: BUG: soft lockup in __perf_sw_event run #17: crashed: BUG: soft lockup in __perf_sw_event run #18: crashed: KASAN: use-after-free Read in perf_output_read run #19: crashed: BUG: soft lockup in __perf_sw_event testing current HEAD 4e68c9b0763ff55eaa69d6e519f07515f1c9037b testing commit 4e68c9b0763ff55eaa69d6e519f07515f1c9037b with gcc (GCC) 8.4.1 20210217 kernel signature: dbee98244fe953eb806741ce61059fd945300fc739ddedbdba3ef3b55c244ca1 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 40m53.679185942s (build: 25m40.904259163s, test: 14m33.762157918s) the crash still happens on HEAD commit msg: Linux 4.14.239 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout