bisecting fixing commit since d45331b00ddb179e291766617259261c112db872 building syzkaller on 8620c2c2581732b54045bd75ae1220982fbb650f testing commit d45331b00ddb179e291766617259261c112db872 with gcc (GCC) 8.1.0 kernel signature: 56246703601eeee83655878ba89db70fc04b43b1532860cacd30beda5c2a5cbe all runs: crashed: WARNING in untrack_pfn testing current HEAD 359c92c02bfae1a6f1e8e37c298e518fd256642c testing commit 359c92c02bfae1a6f1e8e37c298e518fd256642c with gcc (GCC) 8.1.0 kernel signature: 89d28491289b9bb64301f6442e4048fae969efd2591e1b14e25170e478e7076b all runs: crashed: WARNING in untrack_pfn revisions tested: 2, total time: 27m2.60147684s (build: 12m15.772691682s, test: 14m3.759619767s) the crash still happens on HEAD commit msg: Merge tag 'dax-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm crash: WARNING in untrack_pfn RSP: 002b:00007ffeaace0b48 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004432c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffffffffffff R08: 0000000000000000 R09: 00000000004aa90f R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 00007ffeaace0ba0 R14: 0000000000000000 R15: 0000000000000000 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 13165 at arch/x86/mm/pat/memtype.c:1093 untrack_pfn+0x1cb/0x240 arch/x86/mm/pat/memtype.c:1102 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 13165 Comm: syz-executor201 Not tainted 5.6.0-rc1-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/0x4e3 kernel/panic.c:221 __warn.cold.10+0x25/0x2a 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/memtype.c:1093 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 6c 20 0f 00 48 89 95 30 ff ff ff 48 89 b5 38 ff ff RSP: 0018:ffff88809d42f748 EFLAGS: 00010282 RAX: 00000000ffffffea RBX: 1ffff11013a85eeb RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8a035760 RBP: ffff88809d42f818 R08: ffffed10133fd059 R09: ffffed10133fd059 R10: ffffed10133fd058 R11: ffff888099fe82c3 R12: ffff8880a7a48040 R13: 0000000000000000 R14: ffff88809d42f7f8 R15: ffff88809d42f968 unmap_single_vma+0x144/0x300 mm/memory.c:1279 unmap_vmas+0x1a0/0x2a0 mm/memory.c:1332 exit_mmap+0x25e/0x470 mm/mmap.c:3130 __mmput kernel/fork.c:1082 [inline] mmput+0x121/0x410 kernel/fork.c:1103 dup_mm+0x542/0x1200 kernel/fork.c:1376 copy_mm kernel/fork.c:1416 [inline] copy_process+0x272e/0x6380 kernel/fork.c:2081 _do_fork+0xec/0xc30 kernel/fork.c:2430 __do_sys_clone kernel/fork.c:2585 [inline] __se_sys_clone kernel/fork.c:2566 [inline] __x64_sys_clone+0x176/0x230 kernel/fork.c:2566 do_syscall_64+0xca/0x5f0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4432c9 Code: e8 1c 0d 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffeaace0b48 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004432c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffffffffffff R08: 0000000000000000 R09: 00000000004aa90f R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 00007ffeaace0ba0 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..