damon_sysfs_update_target() returns error code for failures, but its caller, damon_sysfs_set_targets() is ignoring that. The update function seems making no critical change in case of such failures, but the behavior will look like DAMON sysfs is silently ignoring or only partially accepting the user input. Fix it.
Fixes: 19467a950b49 ("mm/damon/sysfs: remove requested targets when online-commit inputs") Cc: stable@vger.kernel.org # 5.19.x Signed-off-by: SeongJae Park sj@kernel.org ---
Note that yet another fix[1] should be applied before this.
[1] https://lore.kernel.org/all/739e6aaf-a634-4e33-98a8-16546379ec9f@moroto.moun...
mm/damon/sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 1dfa96d4de99..7472404456aa 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1203,8 +1203,10 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx,
damon_for_each_target_safe(t, next, ctx) { if (i < sysfs_targets->nr) { - damon_sysfs_update_target(t, ctx, + err = damon_sysfs_update_target(t, ctx, sysfs_targets->targets_arr[i]); + if (err) + return err; } else { if (damon_target_has_pid(ctx)) put_pid(t->pid);