From: SeongJae Park Date: Fri, 28 Feb 2025 17:44:50 +0000 (-0800) Subject: mm/damon/core: initialize damos->walk_completed in damon_new_scheme() X-Git-Tag: v6.14~23^2~11 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=73d7a69de212aebb59f4ff23aae0422e86c488fe;p=thirdparty%2Flinux.git mm/damon/core: initialize damos->walk_completed in damon_new_scheme() The function for allocating and initialize a 'struct damos' object, damon_new_scheme(), is not initializing damos->walk_completed field. Only damos_walk_complete() is setting the field. Hence the field will be eventually set and used correctly from second damos_walk() call for the scheme. But the first damos_walk() could mistakenly not walk on the regions. Actually, a common usage of DAMOS for taking an access pattern snapshot is installing a monitoring-purpose DAMOS scheme, doing damos_walk() to retrieve the snapshot, and then removing the scheme. DAMON user-space tool (damo) also gets runtime snapshot in the way. Hence the problem can continuously happen in such use cases. Initialize it properly in the allocation function. Link: https://lkml.kernel.org/r/20250228174450.41472-1-sj@kernel.org Fixes: bf0eaba0ff9c ("mm/damon/core: implement damos_walk()") Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- diff --git a/mm/damon/core.c b/mm/damon/core.c index de4396519b83b..384935ef4e65e 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -373,6 +373,7 @@ struct damos *damon_new_scheme(struct damos_access_pattern *pattern, * or damon_attrs are updated. */ scheme->next_apply_sis = 0; + scheme->walk_completed = false; INIT_LIST_HEAD(&scheme->filters); scheme->stat = (struct damos_stat){}; INIT_LIST_HEAD(&scheme->list);