bisecting fixing commit since 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae building syzkaller on c2c1d1dd603b7d66d283253ffbd61b8692712bd2 testing commit 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 8bc3431a42478847e6d70578ba5801d3ed569ac8835fdee983319ec5409f7b7f 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: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: crashed: BUG: unable to handle kernel paging request in cfb_imageblit 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 35c4ba160ab6133e548468bd0bd1109990dc7736 testing commit 35c4ba160ab6133e548468bd0bd1109990dc7736 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: bca850426b7fb3e121e195c70456932efe465216aa4ace7bd1bb4cd18d59801e all runs: crashed: unregister_netdevice: waiting for DEV to become free Reproducer flagged being flaky revisions tested: 2, total time: 32m11.994235653s (build: 16m27.826363055s, test: 15m20.33802537s) the crash still happens on HEAD commit msg: Linux 4.14.245 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci0 command 0x0409 tx timeout Bluetooth: hci1 command 0x0409 tx timeout Bluetooth: hci5 command 0x0409 tx timeout unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci0 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci4 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci5 command 0x0419 tx timeout Bluetooth: hci1 command 0x0419 tx timeout Bluetooth: hci0 command 0x0419 tx timeout Bluetooth: hci3 command 0x0419 tx timeout Bluetooth: hci4 command 0x0419 tx timeout Bluetooth: hci2 command 0x0419 tx timeout