path: root/drivers/sh
diff options
authorJohannes Weiner <hannes@cmpxchg.org>2016-12-12 16:43:43 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 18:55:08 -0800
commit6d75f366b9242f9b17ed7d0b0604d7460f818f21 (patch)
treed2225813a4c3f435e79273780eac7b1f7b2ecf67 /drivers/sh
parentf7942430e40f14c6d2ca48a1875add509938c07d (diff)
lib: radix-tree: check accounting of existing slot replacement users
The bug in khugepaged fixed earlier in this series shows that radix tree slot replacement is fragile; and it will become more so when not only NULL<->!NULL transitions need to be caught but transitions from and to exceptional entries as well. We need checks. Re-implement radix_tree_replace_slot() on top of the sanity-checked __radix_tree_replace(). This requires existing callers to also pass the radix tree root, but it'll warn us when somebody replaces slots with contents that need proper accounting (transitions between NULL entries, real entries, exceptional entries) and where a replacement through the slot pointer would corrupt the radix tree node counts. Link: http://lkml.kernel.org/r/20161117193021.GB23430@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/sh')
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/sh/intc/virq.c b/drivers/sh/intc/virq.c
index e7899624aa0b..35bbe288ddb4 100644
--- a/drivers/sh/intc/virq.c
+++ b/drivers/sh/intc/virq.c
@@ -254,7 +254,7 @@ restart:
radix_tree_tag_clear(&d->tree, entry->enum_id,
- radix_tree_replace_slot((void **)entries[i],
+ radix_tree_replace_slot(&d->tree, (void **)entries[i],