bisecting fixing commit since 5ee93551c703f8fa1a6c414a7d08f956de311df3 building syzkaller on d797d2018f9550530c469ce03b5ae36cfa1ebd23 testing commit 5ee93551c703f8fa1a6c414a7d08f956de311df3 with gcc (GCC) 8.1.0 kernel signature: ac8889d37057b536909a63634ae35d59054e175effc97184d52dc88a7828b11c run #0: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #1: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #2: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #3: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #4: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing current HEAD 339485c9a80f3b9f30708f784346fef42ad127c3 testing commit 339485c9a80f3b9f30708f784346fef42ad127c3 with gcc (GCC) 8.1.0 kernel signature: a616285948fd52d0df07948eed8b34ddb4f713fdd64515ec5e26232be2a3e578 run #0: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #1: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #2: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #3: crashed: BUG: unable to handle kernel paging request in init_srcu_struct_fields run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 38m16.163639333s (build: 17m43.254500501s, test: 19m37.393768959s) the crash still happens on HEAD commit msg: Linux 4.19.110 crash: BUG: unable to handle kernel paging request in init_srcu_struct_fields BUG: unable to handle kernel paging request at ffffc900095d98a8 PGD 12c2f0067 P4D 12c2f0067 PUD 21bc31067 PMD 82277067 PTE 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 12682 Comm: syz-executor.0 Not tainted 4.19.110-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:init_srcu_struct_nodes kernel/rcu/srcutree.c:157 [inline] RIP: 0010:init_srcu_struct_fields+0xc1a/0x1340 kernel/rcu/srcutree.c:187 Code: 88 00 00 00 48 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 74 08 3c 03 0f 8e 00 03 00 00 49 8d bd 98 01 00 00 44 89 f1 b8 01 00 00 00 <41> 2b 8c 24 88 00 00 00 48 89 fa 48 c1 ea 03 d3 e0 80 3c 1a 00 48 RSP: 0018:ffff888095857ae8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: 0000000000000001 RDX: 0000000000000004 RSI: 0000000000000001 RDI: ffff8880aeb00198 RBP: ffff888095857bc0 R08: ffffed1015d44733 R09: 0000000000000000 R10: ffffed1015d44732 R11: ffff8880aea23993 R12: ffffc900095d9820 R13: ffff8880aeb00000 R14: 0000000000000001 R15: ffff8880aeb000f0 FS: 00007f67aa143700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc900095d98a8 CR3: 00000000a16cc000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __init_srcu_struct+0x54/0x60 kernel/rcu/srcutree.c:203 kvm_page_track_init+0x22/0x60 arch/x86/kvm/page_track.c:177 kvm_arch_init_vm+0x4a9/0x5f0 arch/x86/kvm/x86.c:9061 kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:683 [inline] kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3270 [inline] kvm_dev_ioctl+0x321/0x1540 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3322 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f67aa142c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219 RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f67aa1436d4 R13: 00000000004c348b R14: 00000000004d7708 R15: 00000000ffffffff Modules linked in: CR2: ffffc900095d98a8 ---[ end trace 2723aa4a16143ee2 ]--- RIP: 0010:init_srcu_struct_nodes kernel/rcu/srcutree.c:157 [inline] RIP: 0010:init_srcu_struct_fields+0xc1a/0x1340 kernel/rcu/srcutree.c:187 Code: 88 00 00 00 48 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 74 08 3c 03 0f 8e 00 03 00 00 49 8d bd 98 01 00 00 44 89 f1 b8 01 00 00 00 <41> 2b 8c 24 88 00 00 00 48 89 fa 48 c1 ea 03 d3 e0 80 3c 1a 00 48 RSP: 0018:ffff888095857ae8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: 0000000000000001 RDX: 0000000000000004 RSI: 0000000000000001 RDI: ffff8880aeb00198 RBP: ffff888095857bc0 R08: ffffed1015d44733 R09: 0000000000000000 R10: ffffed1015d44732 R11: ffff8880aea23993 R12: ffffc900095d9820 R13: ffff8880aeb00000 R14: 0000000000000001 R15: ffff8880aeb000f0 FS: 00007f67aa143700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc900095d98a8 CR3: 00000000a16cc000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400