Dear stable maintainers, The patch "kfence: use TASK_IDLE when awaiting allocation" has landed in mainline as 8fd0e995cc7b, however, does not apply cleanly to 5.12.y due to a prerequisite patch missing. My recommendation is to cherry-pick the following 2 commits to 5.12.y (rather than rebase 8fd0e995cc7b on top of 5.12.y): 37c9284f6932 kfence: maximize allocation wait timeout duration 8fd0e995cc7b kfence: use TASK_IDLE when awaiting allocation Many thanks, -- Marco ---------- Forwarded message --------- From: Marco Elver <elver@xxxxxxxxxx> Date: Fri, 21 May 2021 at 10:32 Subject: [PATCH] kfence: use TASK_IDLE when awaiting allocation To: <elver@xxxxxxxxxx>, <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: <glider@xxxxxxxxxx>, <dvyukov@xxxxxxxxxx>, <linux-kernel@xxxxxxxxxxxxxxx>, <linux-mm@xxxxxxxxx>, <kasan-dev@xxxxxxxxxxxxxxxx>, Mel Gorman <mgorman@xxxxxxx>, <stable@xxxxxxxxxxxxxxx> Since wait_event() uses TASK_UNINTERRUPTIBLE by default, waiting for an allocation counts towards load. However, for KFENCE, this does not make any sense, since there is no busy work we're awaiting. Instead, use TASK_IDLE via wait_event_idle() to not count towards load. BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1185565 Fixes: 407f1d8c1b5f ("kfence: await for allocation using wait_event") Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v5.12+ --- mm/kfence/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
