[0/3] add support for never printing hashed addresses

Message

Timur Tabi Feb. 10, 2021, 5:05 a.m. UTC

[The list of email addresses on CC: is getting quite lengthy,
so I hope I've included everyone.]

Although hashing addresses printed via printk does make the
kernel more secure, it interferes with debugging, especially
with some functions like print_hex_dump() which always uses
hashed addresses.

To avoid having to choose between %p and %px, it's easier to
add a kernel command line that treats all %p as %px.  This
encourages developers to use %p more without making debugging
more difficult.

Patches #1 and #2 upgrade the kselftest framework so that
it can report on tests that were skipped outright.  This
is needed for the test_printf module which will now skip
%p hashing tests if hashing is disabled.

Patch #2 upgrades the printf library to check the command
line.  It also updates test_printf().

Timur Tabi (3):
  lib/test_printf: use KSTM_MODULE_GLOBALS macro
  kselftest: add support for skipped tests
  [v2] lib/vsprintf: make-printk-non-secret printks all addresses as
    unhashed

 .../admin-guide/kernel-parameters.txt         | 15 +++++++
 lib/test_printf.c                             | 12 +++++-
 lib/vsprintf.c                                | 40 ++++++++++++++++++-
 tools/testing/selftests/kselftest_module.h    | 18 ++++++---
 4 files changed, 75 insertions(+), 10 deletions(-)