bisecting fixing commit since f8788d86ab28f61f7b46eb6be375f8a726783636 building syzkaller on 59b57593586656c1d5be820aeed0e751087e6ac6 testing commit f8788d86ab28f61f7b46eb6be375f8a726783636 with gcc (GCC) 8.1.0 kernel signature: 62050ca76ad227ec8acbd57a53dc0db2af7093cb2ab43447a17bf7177f15c0e3 all runs: crashed: general protection fault in ipvlan_hard_header testing current HEAD 42f82040ee66db13525dc6f14b8559890b2f4c1c testing commit 42f82040ee66db13525dc6f14b8559890b2f4c1c with gcc (GCC) 8.1.0 kernel signature: bfc3810f80be07f193bc87ad467fef41552ac8672675cc72b16820a8258d33e8 all runs: crashed: BUG: unable to handle kernel paging request in ipvlan_hard_header revisions tested: 2, total time: 19m54.072167853s (build: 10m47.525042259s, test: 8m36.822496701s) the crash still happens on HEAD commit msg: Merge tag 'drm-fixes-2020-07-10' of git://anongit.freedesktop.org/drm/drm crash: BUG: unable to handle kernel paging request in ipvlan_hard_header BUG: unable to handle page fault for address: 000000010000034f #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 1201b3067 P4D 1201b3067 PUD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ipvlan_hard_header+0x2e/0x40 drivers/net/ipvlan/ipvlan_main.c:360 Code: 8b b6 e0 0b 00 00 74 22 48 8b 86 10 02 00 00 48 85 c0 74 13 48 8b 00 48 85 c0 74 0b 55 0f b7 d2 48 89 e5 ff d0 5d c3 31 c0 c3 <4c> 8b 86 50 03 00 00 eb d5 66 0f 1f 84 00 00 00 00 00 8b 87 28 0c RSP: 0018:ffffc90000003be0 EFLAGS: 00010246 RAX: ffffffff8222a550 RBX: ffff88811fb4e600 RCX: ffff88810b9461a0 RDX: 00000000000086dd RSI: 00000000ffffffff RDI: ffff88811fb4e600 RBP: ffffc90000003c10 R08: 0000000000000000 R09: 0000000000000060 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88811f9ac000 R13: ffff88810b946138 R14: ffff88810b946000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000010000034f CR3: 00000001201b2000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0x3a9/0x9e0 net/ipv6/ip6_output.c:117 __ip6_finish_output+0xd6/0x240 net/ipv6/ip6_output.c:143 ip6_finish_output+0x27/0xa0 net/ipv6/ip6_output.c:153 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x7d/0x2b0 net/ipv6/ip6_output.c:176 dst_output include/net/dst.h:435 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] mld_sendpack+0x2b5/0x380 net/ipv6/mcast.c:1679 mld_send_cr net/ipv6/mcast.c:1975 [inline] mld_ifc_timer_expire+0x1c1/0x350 net/ipv6/mcast.c:2474 call_timer_fn+0xa7/0x320 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] run_timer_softirq+0x1e5/0x5b0 kernel/time/timer.c:1786 __do_softirq+0xf0/0x509 kernel/softirq.c:292 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0xa7/0xc0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:387 [inline] __irq_exit_rcu kernel/softirq.c:417 [inline] irq_exit_rcu+0xcb/0xf0 kernel/softirq.c:429 sysvec_apic_timer_interrupt+0x65/0x120 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:587 RIP: 0010:native_safe_halt+0x12/0x20 arch/x86/include/asm/irqflags.h:61 Code: 20 48 8b 00 a8 08 75 c2 e9 7b ff ff ff cc cc cc cc cc cc cc cc cc cc cc 55 48 89 e5 e9 07 00 00 00 0f 00 2d 88 75 55 00 fb f4 <5d> c3 66 90 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 e9 07 00 00 RSP: 0018:ffffffff84203d80 EFLAGS: 00000286 RAX: 000000000003fe71 RBX: ffff88821b0b0800 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff830c94b1 RBP: ffffffff84203d80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88821b0b0864 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000001 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] acpi_idle_do_entry+0x50/0x80 drivers/acpi/processor_idle.c:525 acpi_idle_enter+0xff/0x300 drivers/acpi/processor_idle.c:651 cpuidle_enter_state+0x67/0x430 drivers/cpuidle/cpuidle.c:235 cpuidle_enter+0x29/0x40 drivers/cpuidle/cpuidle.c:346 call_cpuidle kernel/sched/idle.c:126 [inline] cpuidle_idle_call kernel/sched/idle.c:214 [inline] do_idle+0x280/0x370 kernel/sched/idle.c:276 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:372 rest_init+0x174/0x237 init/main.c:705 arch_call_rest_init+0x9/0xc start_kernel+0x582/0x5a2 init/main.c:1043 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x71/0x74 arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 Modules linked in: CR2: 000000010000034f ---[ end trace 1f30282509296a45 ]--- RIP: 0010:ipvlan_hard_header+0x2e/0x40 drivers/net/ipvlan/ipvlan_main.c:360 Code: 8b b6 e0 0b 00 00 74 22 48 8b 86 10 02 00 00 48 85 c0 74 13 48 8b 00 48 85 c0 74 0b 55 0f b7 d2 48 89 e5 ff d0 5d c3 31 c0 c3 <4c> 8b 86 50 03 00 00 eb d5 66 0f 1f 84 00 00 00 00 00 8b 87 28 0c RSP: 0018:ffffc90000003be0 EFLAGS: 00010246 RAX: ffffffff8222a550 RBX: ffff88811fb4e600 RCX: ffff88810b9461a0 RDX: 00000000000086dd RSI: 00000000ffffffff RDI: ffff88811fb4e600 RBP: ffffc90000003c10 R08: 0000000000000000 R09: 0000000000000060 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88811f9ac000 R13: ffff88810b946138 R14: ffff88810b946000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000010000034f CR3: 00000001201b2000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400