------------[ cut here ]------------
mm == current->mm
WARNING: kernel/fork.c:721 at __mmdrop+0x5de/0x750 kernel/fork.c:721, CPU#0: syz.0.21/6011
Modules linked in:
CPU: 0 UID: 0 PID: 6011 Comm: syz.0.21 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:__mmdrop+0x5de/0x750 kernel/fork.c:721
Code: 00 90 0f 0b e8 e3 b8 41 00 90 0f 0b 90 e9 e9 fa ff ff e8 d5 b8 41 00 48 89 df e8 fd 05 aa 00 e9 c0 fb ff ff e8 c3 b8 41 00 90 <0f> 0b 90 e9 85 fa ff ff e8 b5 b8 41 00 90 0f 0b 90 e9 5f fb ff ff
RSP: 0018:ffffc900031d78f0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88802c1e6200 RCX: ffffffff81d45fb6
RDX: ffff88802d5b8000 RSI: ffffffff81c4b43d RDI: ffff88802d5b8570
RBP: ffffc900031d7988 R08: 0000000000000001 R09: ffffed100583cc40
R10: ffff88802c1e6203 R11: 0000000000000000 R12: ffff88802d5b8000
R13: ffff88801e6bdac0 R14: ffff88802e53dac0 R15: ffff8880b843beb0
FS:  00007f26579c36c0(0000) GS:ffff8881245a5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f963fff CR3: 000000002520c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 mmdrop include/linux/sched/mm.h:55 [inline]
 mmdrop_sched include/linux/sched/mm.h:83 [inline]
 mmdrop_lazy_tlb_sched include/linux/sched/mm.h:110 [inline]
 finish_task_switch.isra.0+0x779/0xb80 kernel/sched/core.c:5177
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x102b/0x6000 kernel/sched/core.c:6907
 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7091
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 class_preempt_destructor include/linux/preempt.h:468 [inline]
 try_to_wake_up+0x644/0x1a80 kernel/sched/core.c:4094
 wake_up_process kernel/sched/core.c:4374 [inline]
 wake_up_q+0xa1/0x130 kernel/sched/core.c:1100
 futex_wake+0x460/0x530 kernel/futex/waitwake.c:198
 do_futex+0x32b/0x350 kernel/futex/syscalls.c:135
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex kernel/futex/syscalls.c:188 [inline]
 __x64_sys_futex+0x34f/0x4d0 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2656b9bf79
Code: Unable to access opcode bytes at 0x7f2656b9bf4f.
RSP: 002b:00007f26579c30e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f2656e15fa8 RCX: 00007f2656b9bf79
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f2656e15fac
RBP: 00007f2656e15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2656e16038 R14: 00007ffdb8798d50 R15: 00007ffdb8798e38
 </TASK>