BUG: sleeping function called from invalid context at mm/vmalloc.c:3409
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5974, name: syz-executor
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<ffffffff812c5d36>] preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
CPU: 0 UID: 0 PID: 5974 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
 __might_resched+0x3c0/0x5e0 kernel/sched/core.c:8957
 vfree+0x75/0xb50 mm/vmalloc.c:3409
 futex_hash_free+0x98/0xc0 kernel/futex/core.c:1742
 __mmdrop+0x33f/0x580 kernel/fork.c:692
 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+0x7a4/0xc10 kernel/sched/core.c:5250
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1198/0x5de0 kernel/sched/core.c:6961
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7145
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_read_unlock include/linux/rwlock_api_smp.h:233 [inline]
 _raw_read_unlock+0x3e/0x50 kernel/locking/spinlock.c:260
 kill_something_info+0x10c/0x310 kernel/signal.c:1603
 __do_sys_kill kernel/signal.c:3955 [inline]
 __se_sys_kill kernel/signal.c:3949 [inline]
 __ia32_sys_kill+0xd7/0x140 kernel/signal.c:3949
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf70ce579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ffa7182c EFLAGS: 00000297 ORIG_RAX: 0000000000000025
RAX: ffffffffffffffda RBX: 00000000ffffe9d4 RCX: 0000000000000009
RDX: 00000000f7434ff4 RSI: 0000000000000064 RDI: 0000000000000b1f
RBP: 000000000000162c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi