Commit 99826790 authored Apr 16, 2019 by Andrea Parri Committed by Greg Kroah-Hartman Apr 25, 2019

kernfs: fix barrier usage in __kernfs_new_node()



smp_mb__before_atomic() can not be applied to atomic_set().  Remove the
barrier and rely on RELEASE synchronization.

Fixes: ba16b284 ("kernfs: add an API to get kernfs node from inode number")
Cc: stable@vger.kernel.org
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0d1a393d

fs/kernfs/dir.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -650,11 +650,10 @@ static struct kernfs_node __kernfs_new_node(struct kernfs_root root,
		kn->id.generation = gen;

		/*
		* set ino first. This barrier is paired with atomic_inc_not_zero in
		* set ino first. This RELEASE is paired with atomic_inc_not_zero in
		* kernfs_find_and_get_node_by_ino
		*/
		smp_mb__before_atomic();
		atomic_set(&kn->count, 1);
		atomic_set_release(&kn->count, 1);
		atomic_set(&kn->active, KN_DEACTIVATED_BIAS);
		RB_CLEAR_NODE(&kn->rb);

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