将page的flags转换为可读字符串
crash> kmem -g 01fffe00000a001c
FLAGS: 1fffe00000a001c
PAGE-FLAG BIT VALUE
PG_referenced 2 0000004
PG_uptodate 3 0000008
PG_dirty 4 0000010
PG_reclaim 17 0020000
PG_unevictable 19 0080000
PG_savepinned 4 0000010
PG_isolated 17 0020000
此外，可以用whatis查看pageflags的定义:
crash> whatis pageflags
enum pageflags {
PG_locked = 0
PG_error = 1
PG_referenced = 2
PG_uptodate = 3
PG_dirty = 4
PG_lru = 5
PG_active = 6
PG_waiters = 7
PG_slab = 8
PG_owner_priv_1 = 9
PG_arch_1 = 10
PG_reserved = 11
PG_private = 12
PG_private_2 = 13
PG_writeback = 14
PG_head = 15
PG_mappedtodisk = 16
PG_reclaim = 17
PG_swapbacked = 18
PG_unevictable = 19
PG_mlocked = 20
PG_uncached = 21
PG_hwpoison = 22
PG_young = 23
PG_idle = 24
PG_workingset = 25
__NR_PAGEFLAGS = 26
PG_checked = 9
PG_swapcache = 9
PG_fscache = 13
PG_pinned = 9
PG_savepinned = 4
PG_foreign = 9
PG_slob_free = 12
PG_double_map = 13
PG_isolated = 17
};
上面__NR_PAGEFLAGS表示flags中前26位用于表示page的状态，所以在转换时会忽略标志位的无效位。
将vma的flags转换为可读的字符
crash> vm -f 8000875
8000875: (READ|EXEC|MAYREAD|MAYWRITE|MAYEXEC|DENYWRITE|CAN_NONLINEAR)