syzbot

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BUG: KCSAN: data-race in __do_munmap / task_mem

write to 0xffff888107a524c0 of 8 bytes by task 13502 on cpu 1:
 vm_stat_account mm/mmap.c:3366 [inline]
 remove_vma_list mm/mmap.c:2656 [inline]
 __do_munmap+0xfa4/0x1330 mm/mmap.c:2915
 __vm_munmap+0x98/0x160 mm/mmap.c:2935
 __do_sys_munmap mm/mmap.c:2961 [inline]
 __se_sys_munmap mm/mmap.c:2957 [inline]
 __x64_sys_munmap+0x3d/0x50 mm/mmap.c:2957
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888107a524c0 of 8 bytes by task 1021 on cpu 0:
 task_mem+0xb7/0x3d0 fs/proc/task_mmu.c:46
 proc_pid_status+0x80b/0x13c0 fs/proc/array.c:448
 proc_single_show+0x84/0x100 fs/proc/base.c:774
 seq_read_iter+0x2ef/0x910 fs/seq_file.c:227
 seq_read+0x221/0x260 fs/seq_file.c:159
 vfs_read+0x154/0x5d0 fs/read_write.c:494
 ksys_read+0xce/0x180 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000027a1 -> 0x0000000000002569

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1021 Comm: systemd-journal Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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