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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230821142051.31889-1-abelova@astralinux.ru> X-Rspam-User: X-Stat-Signature: tjo7zsuxj71zwjiaq1gk87dt7b3dt3cu X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: F28FA4000B X-HE-Tag: 1692628234-189811 X-HE-Meta: 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 rxEEaPLZ 7gwP1b5X2aT3ndPTIAQg5XZ6CNkxzEMwANnPgAtFEyh+anoIzOBXRrSd4jhM7vW49RWyLRUvt6Hox3GQcOkbJIo8jrCIdUECDFzXSh+CuJ220l1tKgatUH7e52LSvtHdc925zYwy4oY56ltKGCzRW92IwgnHF/lfBZ8tgBsSKz0fK08JhVq9BVuJzRy25Z1Q0O/EiNpZnbD6x0G0TIsQGlsFN9YyI8PS2t6MXortTk3/cYx6NE1JzTI2QjUi5IFDZxRaKIJtr+3POhIOkqF30XbpJ64VKrfSfg5hmkfrNIN1v9jpQxd4Oyimjk30ySNnhJ95mW+lOus0IIte2rOsHnqrBLfvUh5eapwOvxmq3LyYg3AAfuMpXJ3ftJrG5TsVKActx8oQtmpzIwKc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 21-08-23 17:20:51, Anastasia Belova wrote: > kzalloc_node may return NULL. So rtpn should be > checked before dereference in mem_cgroup_init. I do not think this is an appropriate fix. If the allocation really fails (which is essentially impossible as this is an early boot code and failing 24B req. this early means the system will likely die anyway) then we will crash on NULL ptr dereference right afterwards so WARN will not give us anything usefull on top. So either this needs a graceful way to deal with the allocation failure or considering the previously said just keep the code alone and teach the tooling that this should be ignored. > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: 95a045f63d98 ("mm: memcontrol: consolidate memory controller initialization") > Signed-off-by: Anastasia Belova Nacked-by: Michal Hocko Thanks! > --- > mm/memcontrol.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index e8ca4bdcb03c..7998dbf3c7cd 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -7377,6 +7377,7 @@ static int __init mem_cgroup_init(void) > struct mem_cgroup_tree_per_node *rtpn; > > rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, node); > + WARN_ON(!rtpn); > > rtpn->rb_root = RB_ROOT; > rtpn->rb_rightmost = NULL; > -- > 2.30.2 -- Michal Hocko SUSE Labs