Commit 5578534e authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

unwind: Simplify unwind_user_next_fp() alignment check 



  2^log_2(n) == n

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Link: https://patch.msgid.link/20250924080119.497867836@infradead.org
parent 639214f6

kernel/unwind/user.c

+1 −3
Original line number Diff line number Diff line
@@ -19,7 +19,6 @@ static int unwind_user_next_fp(struct unwind_user_state *state) 
{

	const struct unwind_user_frame *frame = &fp_frame;

	unsigned long cfa, fp, ra;

	unsigned int shift;



	if (frame->use_fp) {

		if (state->fp < state->sp)
@@ -37,8 +36,7 @@ static int unwind_user_next_fp(struct unwind_user_state *state) 
		return -EINVAL;



	/* Make sure that the address is word aligned */

	shift = sizeof(long) == 4 ? 2 : 3;

	if (cfa & ((1 << shift) - 1))

	if (cfa & (sizeof(long) - 1))

		return -EINVAL;



	/* Find the Return Address (RA) */