bisecting fixing commit since 23203e3f34c97f4ddd6e353adba45161880a52a4
building syzkaller on e3bd7ab805a9a4541c9fe135ec90c95089f49153
testing commit 23203e3f34c97f4ddd6e353adba45161880a52a4 with gcc (GCC) 8.1.0
kernel signature: 0b297f8e3bc0ec9b4685863b7181459068f727f5
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: OK
run #9: OK
testing current HEAD 6794862a16ef41f753abd75c03a152836e4c8028
testing commit 6794862a16ef41f753abd75c03a152836e4c8028 with gcc (GCC) 8.1.0
kernel signature: f6b3a80fc70be403e5fa893d0619737aa8d86ad8
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: 36m0.564519094s (build: 14m22.133927597s, test: 20m37.414447281s)
the crash still happens on HEAD
commit msg: Merge tag 'for-5.5-rc1-kconfig-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
crash: WARNING in untrack_pfn
------------[ cut here ]------------
WARNING: CPU: 1 PID: 17547 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: 17547 Comm: syz-executor5 Not tainted 5.5.0-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/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:ffff8881a73777b0 EFLAGS: 00010282
RAX: 00000000ffffffea RBX: 1ffff11034e6eef8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff89d87720
RBP: ffff8881a7377880 R08: ffffed1038a0eb2a R09: ffffed1038a0eb2a
R10: ffffed1038a0eb29 R11: ffff8881c507594b R12: ffff8881d259ee70
R13: 0000000000000000 R14: ffff8881a7377860 R15: ffff8881a73779d0
 unmap_single_vma+0x144/0x300 mm/memory.c:1279
 unmap_vmas+0x1a0/0x2a0 mm/memory.c:1332
 exit_mmap+0x25e/0x470 mm/mmap.c:3140
 __mmput kernel/fork.c:1082 [inline]
 mmput+0x121/0x410 kernel/fork.c:1103
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x94d/0x2e50 kernel/exit.c:784
 do_group_exit+0xf4/0x2e0 kernel/exit.c:895
 get_signal+0x36c/0x1d40 kernel/signal.c:2734
 do_signal+0x87/0x1710 arch/x86/kernel/signal.c:815
 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
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4577b9
Code: Bad RIP value.
RSP: 002b:00007fca5f768cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 000000000072bfa8 RCX: 00000000004577b9
RDX: 00000000004c3657 RSI: 0000000000000081 RDI: 000000000072bfac
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072bfac
R13: 00007ffdb1c49def R14: 00007fca5f7699c0 R15: 000000000072bfac
Kernel Offset: disabled
Rebooting in 86400 seconds..