bisecting fixing commit since 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae building syzkaller on c2c1d1dd603b7d66d283253ffbd61b8692712bd2 testing commit 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae with gcc (GCC) 8.4.1 20210217 kernel signature: 56bc5af89fb53746b61bd98229f66facb15e1ee15adf03e19e42e12d11e28e3a run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #2: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #3: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #4: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #5: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #6: crashed: BUG: unable to handle kernel paging request in cfb_imageblit 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 a6b2dae3ee3a3f9f4db3fab5b4b9e493fecf4acd testing commit a6b2dae3ee3a3f9f4db3fab5b4b9e493fecf4acd with gcc (GCC) 8.4.1 20210217 kernel signature: 0b23e68982168f48024145636ed900c988556ebf11125b125b02ddc245e4e5a7 all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 36m13.556580483s (build: 20m16.076654187s, test: 15m26.125356239s) the crash still happens on HEAD commit msg: Linux 4.14.235 crash: unregister_netdevice: waiting for DEV to become free unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f 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: hci1 command 0x040f tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout