bisecting fixing commit since 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae building syzkaller on c2c1d1dd603b7d66d283253ffbd61b8692712bd2 testing commit 3f2ecb86cb909da0b9157fd2952ad79924cbe5ae compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: bc55ad767ffcb2d96bdd89e3a0094e82db868371e3a33d0b49e2417ec4b610e1 run #0: crashed: kernel BUG in ext4_writepages run #1: crashed: kernel BUG in ext4_writepages run #2: crashed: kernel BUG in ext4_writepages run #3: crashed: kernel BUG in ext4_writepages run #4: crashed: kernel BUG in ext4_writepages run #5: crashed: kernel BUG in ext4_writepages run #6: crashed: kernel BUG in ext4_writepages run #7: crashed: kernel BUG in ext4_writepages run #8: crashed: kernel BUG in ext4_writepages run #9: crashed: kernel BUG in ext4_writepages run #10: crashed: kernel BUG in ext4_writepages run #11: crashed: kernel BUG in corrupted run #12: crashed: kernel BUG in ext4_writepages run #13: crashed: kernel BUG in ext4_writepages run #14: crashed: kernel BUG in ext4_writepages run #15: crashed: kernel BUG in ext4_writepages run #16: crashed: kernel BUG in ext4_writepages run #17: crashed: kernel BUG in ext4_writepages run #18: crashed: kernel BUG in ext4_writepages run #19: crashed: kernel BUG in ext4_writepages testing current HEAD 66722c42ec916e92cadda46316f8f6e3fdcaedc6 testing commit 66722c42ec916e92cadda46316f8f6e3fdcaedc6 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e266d7d3472e4454b5b4df6e18f673eb2dc898141e73237629fa73136bcaa695 all runs: crashed: unregister_netdevice: waiting for DEV to become free revisions tested: 2, total time: 28m52.272221453s (build: 21m31.590821096s, test: 6m39.981371317s) the crash still happens on HEAD commit msg: Linux 4.14.256 crash: unregister_netdevice: waiting for DEV to become free Bluetooth: hci4 command 0x0409 tx timeout Bluetooth: hci3 command 0x0409 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci0 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: hci0 command 0x041b tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci5 command 0x041b tx timeout Bluetooth: hci3 command 0x041b tx timeout Bluetooth: hci1 command 0x041b tx timeout Bluetooth: hci3 command 0x040f tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci4 command 0x040f tx timeout Bluetooth: hci5 command 0x040f tx timeout Bluetooth: hci0 command 0x040f tx timeout Bluetooth: hci1 command 0x040f 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 Bluetooth: hci1 command 0x0419 tx timeout