bisecting fixing commit since 23203e3f34c97f4ddd6e353adba45161880a52a4 building syzkaller on e3bd7ab805a9a4541c9fe135ec90c95089f49153 testing commit 23203e3f34c97f4ddd6e353adba45161880a52a4 with gcc (GCC) 8.1.0 kernel signature: 93e324a0d6863deea8589018c570b29db514c20f run #0: crashed: WARNING in untrack_pfn run #1: crashed: WARNING in untrack_pfn run #2: crashed: WARNING in untrack_pfn run #3: crashed: WARNING in untrack_pfn run #4: crashed: WARNING in untrack_pfn run #5: crashed: WARNING in untrack_pfn run #6: crashed: WARNING in untrack_pfn run #7: crashed: WARNING in untrack_pfn run #8: crashed: WARNING in untrack_pfn run #9: OK testing current HEAD b3a987b0264d3ddbb24293ebff10eddfc472f653 testing commit b3a987b0264d3ddbb24293ebff10eddfc472f653 with gcc (GCC) 8.1.0 kernel signature: 71381adead0803734f09d7850376b5df5f48e89d run #0: crashed: WARNING in untrack_pfn run #1: crashed: WARNING in untrack_pfn run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 32m53.775589563s (build: 11m28.635793988s, test: 20m41.511008662s) the crash still happens on HEAD commit msg: Linux 5.5-rc6 crash: WARNING in untrack_pfn ------------[ cut here ]------------ WARNING: CPU: 1 PID: 31997 at arch/x86/mm/pat.c:1065 untrack_pfn+0x1cb/0x240 arch/x86/mm/pat.c:1074 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 31997 Comm: syz-executor1 Not tainted 5.5.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x12d/0x187 lib/dump_stack.c:118 panic+0x22a/0x4f5 kernel/panic.c:221 __warn.cold.10+0x25/0x28 kernel/panic.c:582 report_bug+0x1b0/0x270 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:untrack_pfn+0x1cb/0x240 arch/x86/mm/pat.c:1065 Code: 00 00 00 48 c7 43 08 00 00 00 00 48 8b 45 d8 65 48 33 04 25 28 00 00 00 75 14 48 81 c4 b0 00 00 00 5b 41 5c 41 5d 41 5e 5d c3 <0f> 0b eb c1 e8 0c b4 0f 00 48 89 95 30 ff ff ff 48 89 b5 38 ff ff RSP: 0018:ffff8881c1e3f7c0 EFLAGS: 00010282 RAX: 00000000ffffffea RBX: 1ffff110383c7efa RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff89d88720 RBP: ffff8881c1e3f890 R08: ffffed103ae632dd R09: ffffed103ae632dd kobject: 'loop0' (000000000969e713): kobject_uevent_env R10: ffffed103ae632dc R11: ffff8881d73196e3 R12: ffff8881c0473738 R13: 0000000000000000 R14: ffff8881c1e3f870 R15: ffff8881c1e3f9e0 kobject: 'loop0' (000000000969e713): fill_kobj_path: path = '/devices/virtual/block/loop0' unmap_single_vma+0x144/0x300 mm/memory.c:1279 unmap_vmas+0x1a0/0x2a0 mm/memory.c:1332 exit_mmap+0x25e/0x470 mm/mmap.c:3134 kobject: 'loop3' (000000008eabc0e3): kobject_uevent_env __mmput kernel/fork.c:1082 [inline] mmput+0x121/0x410 kernel/fork.c:1103 exit_mm kernel/exit.c:485 [inline] do_exit+0x962/0x2bf0 kernel/exit.c:788 kobject: 'loop3' (000000008eabc0e3): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop0' (000000000969e713): kobject_uevent_env kobject: 'loop0' (000000000969e713): fill_kobj_path: path = '/devices/virtual/block/loop0' do_group_exit+0xf4/0x2e0 kernel/exit.c:899 get_signal+0x36c/0x1d40 kernel/signal.c:2734 do_signal+0x87/0x1710 arch/x86/kernel/signal.c:815 kobject: 'loop3' (000000008eabc0e3): kobject_uevent_env exit_to_usermode_loop+0x114/0x210 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x50b/0x600 arch/x86/entry/common.c:304 kobject: 'loop3' (000000008eabc0e3): fill_kobj_path: path = '/devices/virtual/block/loop3' entry_SYSCALL_64_after_hwframe+0x49/0xbe kobject: 'loop0' (000000000969e713): kobject_uevent_env RIP: 0033:0x4577b9 kobject: 'loop0' (000000000969e713): fill_kobj_path: path = '/devices/virtual/block/loop0' Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 kobject: 'loop2' (00000000988f9a36): kobject_uevent_env RSP: 002b:00007efcf9128cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca kobject: 'loop2' (00000000988f9a36): fill_kobj_path: path = '/devices/virtual/block/loop2' RAX: 0000000000000000 RBX: 000000000072bf08 RCX: 00000000004577b9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072bf08 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072bf0c R13: 00007ffddde24d6f R14: 00007efcf91299c0 R15: 000000000072bf0c Kernel Offset: disabled Rebooting in 86400 seconds..