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charset=us-ascii Content-Disposition: inline In-Reply-To: <20200117022111.18807-1-cai@lca.pw> User-Agent: Mutt/1.10.1 (2018-07-13) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000003, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On (20/01/16 21:21), Qian Cai wrote: > It is not that hard to trigger lockdep splats by calling printk from > under zone->lock. Most of them are false positives caused by lock chains > introduced early in the boot process and they do not cause any real > problems (although some of the early boot lock dependencies could > happenn after boot as well). There are some console drivers which do > allocate from the printk context as well and those should be fixed. In > any case false positives are not that trivial to workaround and it is > far from optimal to lose lockdep functionality for something that is a > non-issue. [..] > > Acked-by: Michal Hocko > Signed-off-by: Qian Cai FWIW, Reviewed-by: Sergey Senozhatsky -ss