syzbot

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BUG: KCSAN: data-race in do_nanosleep / mm_update_next_owner

write to 0xffff88810082802c of 4 bytes by task 1763 on cpu 1:
 freezer_count include/linux/freezer.h:121 [inline]
 freezable_schedule include/linux/freezer.h:173 [inline]
 do_nanosleep+0x121/0x3d0 kernel/time/hrtimer.c:1896
 hrtimer_nanosleep+0xfa/0x1f0 kernel/time/hrtimer.c:1949
 common_nsleep+0x69/0x80 kernel/time/posix-timers.c:1227
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline]
 __se_sys_clock_nanosleep kernel/time/posix-timers.c:1245 [inline]
 __x64_sys_clock_nanosleep+0x1ee/0x220 kernel/time/posix-timers.c:1245
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810082802c of 4 bytes by task 8722 on cpu 0:
 mm_update_next_owner+0x1d9/0x520 kernel/exit.c:389
 exit_mm+0x358/0x450 kernel/exit.c:501
 do_exit+0x3ff/0x1560 kernel/exit.c:813
 do_group_exit+0x19b/0x1a0 kernel/exit.c:923
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:934
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:932
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:932
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x40404140 -> 0x00404140

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8722 Comm: syz-executor.3 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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