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[ 29.403950] Oops: divide error: 0000 [#1] SMP NOPTI This patch fixes the bug, but does not disallow zero size regions to keep the backward compatibility since disallowing zero size regions might be a breaking change for some users. Fixes: f04b0fedbe71 ("mm/damon/core: implement intervals auto-tuning") Signed-off-by: Honggyu Kim Cc: Yunjeong Mun --- mm/damon/core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/damon/core.c b/mm/damon/core.c index b217e0120e09..e274a4d958d6 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1448,7 +1448,10 @@ static unsigned long damon_get_intervals_score(struct damon_ctx *c) access_events += sz_region * r->nr_accesses; } } - target_access_events = max_access_events * goal_bp / 10000; + if (likely(max_access_events) > 0) + target_access_events = max_access_events * goal_bp / 10000; + else + target_access_events = 1; return access_events * 10000 / target_access_events; } -- 2.34.1