Provided by: manpages_6.7-2_all 
NAME
/proc/kpageflags - physical pages frame masks
DESCRIPTION
/proc/kpageflags (since Linux 2.6.25)
This file contains 64-bit masks corresponding to each physical page frame; it is indexed by page
frame number (see the discussion of /proc/pid/pagemap). The bits are as follows:
0 - KPF_LOCKED
1 - KPF_ERROR
2 - KPF_REFERENCED
3 - KPF_UPTODATE
4 - KPF_DIRTY
5 - KPF_LRU
6 - KPF_ACTIVE
7 - KPF_SLAB
8 - KPF_WRITEBACK
9 - KPF_RECLAIM
10 - KPF_BUDDY
11 - KPF_MMAP (since Linux 2.6.31)
12 - KPF_ANON (since Linux 2.6.31)
13 - KPF_SWAPCACHE (since Linux 2.6.31)
14 - KPF_SWAPBACKED (since Linux 2.6.31)
15 - KPF_COMPOUND_HEAD (since Linux 2.6.31)
16 - KPF_COMPOUND_TAIL (since Linux 2.6.31)
17 - KPF_HUGE (since Linux 2.6.31)
18 - KPF_UNEVICTABLE (since Linux 2.6.31)
19 - KPF_HWPOISON (since Linux 2.6.31)
20 - KPF_NOPAGE (since Linux 2.6.31)
21 - KPF_KSM (since Linux 2.6.32)
22 - KPF_THP (since Linux 3.4)
23 - KPF_BALLOON (since Linux 3.18)
24 - KPF_ZERO_PAGE (since Linux 4.0)
25 - KPF_IDLE (since Linux 4.3)
26 - KPF_PGTABLE (since Linux 4.18)
For further details on the meanings of these bits, see the kernel source file
Documentation/admin-guide/mm/pagemap.rst. Before Linux 2.6.29, KPF_WRITEBACK, KPF_RECLAIM,
KPF_BUDDY, and KPF_LOCKED did not report correctly.
The /proc/kpageflags file is present only if the CONFIG_PROC_PAGE_MONITOR kernel configuration
option is enabled.
SEE ALSO
proc(5)
Linux man-pages 6.7 2023-08-15 proc_kpageflags(5)