Documentation: Mention why %p prints ptrval

When debugging recent kernels, people will see '(ptrval)' but there
isn't much information as to what that means. Briefly describe why it's
there.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Acked-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Joel Stanley 2018-03-22 15:53:36 +10:30 committed by Jonathan Corbet
parent bf02d49123
commit 156383b190

View File

@ -60,8 +60,8 @@ Plain Pointers
Pointers printed without a specifier extension (i.e unadorned %p) are
hashed to prevent leaking information about the kernel memory layout. This
has the added benefit of providing a unique identifier. On 64-bit machines
the first 32 bits are zeroed. If you *really* want the address see %px
below.
the first 32 bits are zeroed. The kernel will print ``(ptrval)`` until it
gathers enough entropy. If you *really* want the address see %px below.
Symbols/Function Pointers
-------------------------