]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
maple_tree: add RCU lock checking to rcu callback functions
authorLiam R. Howlett <Liam.Howlett@oracle.com>
Mon, 27 Feb 2023 17:36:06 +0000 (09:36 -0800)
committerAndrew Morton <akpm@linux-foundation.org>
Thu, 6 Apr 2023 01:06:22 +0000 (18:06 -0700)
commit790e1fa86b340c2bd4a327e01c161f7a1ad885f6
tree284ef2d392b55da11b798143aeab4bc149e130dc
parent0a2b18d948838e16912b3b627b504ab062b7d02a
maple_tree: add RCU lock checking to rcu callback functions

Dereferencing RCU objects within the RCU callback without the RCU check
has caused lockdep to complain.  Fix the RCU dereferencing by using the
RCU callback lock to ensure the operation is safe.

Also stop creating a new lock to use for dereferencing during destruction
of the tree or subtree.  Instead, pass through a pointer to the tree that
has the lock that is held for RCU dereferencing checking.  It also does
not make sense to use the maple state in the freeing scenario as the tree
walk is a special case where the tree no longer has the normal encodings
and parent pointers.

Link: https://lkml.kernel.org/r/20230227173632.3292573-8-surenb@google.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
lib/maple_tree.c