6.6-stable review patch. If anyone has any objections, please let me know.
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From: Johannes Weiner hannes@cmpxchg.org
commit 118642d7f606fc9b9c92ee611275420320290ffb upstream.
The swapaccount deprecation warning is throwing false positives. Since we deprecated the knob and defaulted to enabling, the only reports we've been getting are from folks that set swapaccount=1. While this is a nice affirmation that always-enabling was the right choice, we certainly don't want to warn when users request the supported mode.
Only warn when disabling is requested, and clarify the warning.
[colin.i.king@gmail.com: spelling: "commdandline" -> "commandline"] Link: https://lkml.kernel.org/r/20240215090544.1649201-1-colin.i.king@gmail.com Link: https://lkml.kernel.org/r/20240213081634.3652326-1-hannes@cmpxchg.org Fixes: b25806dcd3d5 ("mm: memcontrol: deprecate swapaccounting=0 mode") Signed-off-by: Colin Ian King colin.i.king@gmail.com Reported-by: "Jonas Schäfer" jonas@wielicki.name Reported-by: Narcis Garcia debianlists@actiu.net Suggested-by: Yosry Ahmed yosryahmed@google.com Signed-off-by: Johannes Weiner hannes@cmpxchg.org Reviewed-by: Yosry Ahmed yosryahmed@google.com Acked-by: Michal Hocko mhocko@suse.com Acked-by: Shakeel Butt shakeelb@google.com Cc: Roman Gushchin roman.gushchin@linux.dev Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- mm/memcontrol.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
--- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -7613,9 +7613,13 @@ bool mem_cgroup_swap_full(struct folio *
static int __init setup_swap_account(char *s) { - pr_warn_once("The swapaccount= commandline option is deprecated. " - "Please report your usecase to linux-mm@kvack.org if you " - "depend on this functionality.\n"); + bool res; + + if (!kstrtobool(s, &res) && !res) + pr_warn_once("The swapaccount=0 commandline option is deprecated " + "in favor of configuring swap control via cgroupfs. " + "Please report your usecase to linux-mm@kvack.org if you " + "depend on this functionality.\n"); return 1; } __setup("swapaccount=", setup_swap_account);