x86/stacktrace: Use scoped user access in copy_stack_frame()

copy_stack_frame() reads the two words of a user stack frame with
__get_user(), after an __access_ok() on the frame and inside
pagefault_disable(), since the user stack walk can run in atomic
context.

Do the two reads in a scoped_user_read_access() instead.  It nests
inside the pagefault_disable() section, does the range check itself, and
needs only a single stac/clac pair for both loads.

This is part of getting rid of __get_user() and __put_user() entirely.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

0 files changed, 0 insertions, 0 deletions