Show the access type in KFENCE reports by plumbing through read/write information from the page fault handler. Update the documentation and test accordingly. Link: https://lkml.kernel.org/r/20210111091544.3287013-2-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Suggested-by: Jörn Engel <joern@purestorage.com> Reviewed-by: Jörn Engel <joern@purestorage.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Bug: 177201466 (cherry picked from commit e29117c1fbf30d27d5afe41cf34263e1fd8e4f04 https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10) Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish Signed-off-by: Alexander Potapenko <glider@google.com> Change-Id: I2e9bb224292cf92ac828232c51cd57024ac56d7d