bisecting fixing commit since c6db52a88798e5a0dfef80041ad4d33cc8cf04eb
building syzkaller on 2420d1bcbcd9f5d5893c1aab8096cce81721dac2
testing commit c6db52a88798e5a0dfef80041ad4d33cc8cf04eb with gcc (GCC) 8.4.1 20210217
kernel signature: e173bbaa3150b2b1875342f7f79e474014142d9a08015a880265b766b7b1c7f1
run #0: crashed: KASAN: use-after-free Read in bcm_can_tx
run #1: crashed: WARNING: ODEBUG bug in enqueue_hrtimer
run #2: crashed: KASAN: use-after-free Read in bcm_can_tx
run #3: crashed: KASAN: use-after-free Read in bcm_can_tx
run #4: crashed: KASAN: use-after-free Read in bcm_can_tx
run #5: crashed: KASAN: use-after-free Read in bcm_can_tx
run #6: crashed: KASAN: use-after-free Write in __tasklet_schedule
run #7: crashed: KASAN: use-after-free Read in bcm_can_tx
run #8: crashed: KASAN: use-after-free Read in bcm_can_tx
run #9: crashed: KASAN: use-after-free Read in bcm_can_tx
run #10: crashed: KASAN: use-after-free Read in tasklet_action
run #11: crashed: KASAN: use-after-free Read in tasklet_action
run #12: crashed: KASAN: use-after-free Write in __tasklet_schedule
run #13: crashed: KASAN: use-after-free Read in tasklet_action
run #14: crashed: WARNING: ODEBUG bug in enqueue_hrtimer
run #15: crashed: KASAN: use-after-free Read in hrtimer_debug_hint
run #16: crashed: KASAN: use-after-free Read in tasklet_action
run #17: crashed: KASAN: use-after-free Read in bcm_can_tx
run #18: crashed: KASAN: use-after-free Read in tasklet_action
run #19: OK
testing current HEAD cfb41ef9deb1e6572ac218ddfcec9567e5d1c101
testing commit cfb41ef9deb1e6572ac218ddfcec9567e5d1c101 with gcc (GCC) 8.4.1 20210217
kernel signature: 188470f68b9f264414469fe3bb1f028f68684ff886479b78212411e36c4684f9
all runs: crashed: unregister_netdevice: waiting for DEV to become free
revisions tested: 2, total time: 29m27.724407764s (build: 14m51.953055376s, test: 14m8.32011772s)
the crash still happens on HEAD
commit msg: Linux 4.14.237
crash: unregister_netdevice: waiting for DEV to become free
unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1