bisecting fixing commit since 106fa147d3daa58d2c1ae5f41a29d07036fe7d0a
building syzkaller on 2c2b926cb74478a86014f40564517f7d424dc899
testing commit 106fa147d3daa58d2c1ae5f41a29d07036fe7d0a with gcc (GCC) 8.1.0
kernel signature: 0760202573ba1f014be4cf8d1467cbfec082fc7803af88bc076874c381710dcb
all runs: crashed: WARNING in __vm_enough_memory
testing current HEAD c37da90efff5f183bea6ae4c2af33571f61fe317
testing commit c37da90efff5f183bea6ae4c2af33571f61fe317 with gcc (GCC) 8.1.0
kernel signature: db98b9a66e1a1f6567dda116778afd5516f44163c1a5ddb1d55191e0dfcf2380
all runs: crashed: WARNING in __vm_enough_memory
revisions tested: 2, total time: 27m58.941725266s (build: 20m34.273929009s, test: 5m55.508772869s)
the crash still happens on HEAD
commit msg: Linux 4.19.143
crash: WARNING in __vm_enough_memory
IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready
device veth0_macvtap entered promiscuous mode
IPv6: ADDRCONF(NETDEV_UP): macvtap0: link is not ready
------------[ cut here ]------------
memory commitment underflow
WARNING: CPU: 1 PID: 7831 at mm/util.c:670 __vm_enough_memory+0x3c3/0x4b0 mm/util.c:668
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 7831 Comm: kworker/u4:1 Not tainted 4.19.143-syzkaller #0
device veth1_macvtap entered promiscuous mode
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+0x17c/0x22a lib/dump_stack.c:118
 panic+0x1cd/0x375 kernel/panic.c:186
 __warn.cold.7+0x1b/0x3e kernel/panic.c:541
 report_bug+0x1a4/0x200 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:__vm_enough_memory+0x3c3/0x4b0 mm/util.c:668
Code: ea 02 48 29 d0 e9 3b ff ff ff 80 3d 47 29 9a 07 00 0f 85 ec fc ff ff 48 c7 c7 20 1f 31 87 c6 05 33 29 9a 07 01 e8 b0 93 b6 ff <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14
RSP: 0018:ffff88808e2dfd30 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff8860e8c0 RCX: 1ffff11011c8d552
RDX: 1ffffffff10a40b1 RSI: ffff88808e46aa70 RDI: 0000000000000282
RBP: ffff88808e2dfd68 R08: ffff88808e46aa90 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff88808e2bce40 R14: 0000000000000001 R15: fff800000001a1fa
 security_vm_enough_memory_mm+0x72/0x90 security/security.c:334
 insert_vm_struct+0x1ec/0x310 mm/mmap.c:3121
 __bprm_mm_init fs/exec.c:315 [inline]
 bprm_mm_init fs/exec.c:418 [inline]
 __do_execve_file.isra.12+0xcc1/0x1d40 fs/exec.c:1790
 do_execveat_common fs/exec.c:1866 [inline]
 do_execve+0x20/0x30 fs/exec.c:1883
 call_usermodehelper_exec_async+0x438/0x5b0 kernel/umh.c:107
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Kernel Offset: disabled
Rebooting in 86400 seconds..