bisecting fixing commit since 01364dad1d4577e27a57729d41053f661bb8a5b9
building syzkaller on aa6c6a5572a4797ea6109a75ca50a2c86908375e
testing commit 01364dad1d4577e27a57729d41053f661bb8a5b9 with gcc (GCC) 8.1.0
kernel signature: 59c7ec33b13108709a2354409d718a6e6255a4eac144206f6752f3b1b0333972
all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in l2tp_session_free
testing current HEAD 4139fb08c05fec734f85a99e8b7d99dc12b1b68c
testing commit 4139fb08c05fec734f85a99e8b7d99dc12b1b68c with gcc (GCC) 8.1.0
kernel signature: b44aa4f9d14e882c8351e3af63400427b7491d38b202b7e2788506d68328cc76
all runs: boot failed: WARNING in kvm_mmu_set_mmio_spte_mask
revisions tested: 2, total time: 31m31.328728691s (build: 16m36.467042791s, test: 14m26.556018326s)
bisection is inconclusive, the first good commit could be any of:
01364dad1d4577e27a57729d41053f661bb8a5b9
4139fb08c05fec734f85a99e8b7d99dc12b1b68c