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dkim=pass header.d=stgolabs.net header.s=dreamhost header.b=Znyqx7Rb; dmarc=none; spf=pass (imf26.hostedemail.com: domain of dave@stgolabs.net designates 23.83.214.25 as permitted sender) smtp.mailfrom=dave@stgolabs.net; arc=pass ("mailchannels.net:s=arc-2022:i=1") Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=stgolabs.net header.s=dreamhost header.b=Znyqx7Rb; dmarc=none; spf=pass (imf26.hostedemail.com: domain of dave@stgolabs.net designates 23.83.214.25 as permitted sender) smtp.mailfrom=dave@stgolabs.net; arc=pass ("mailchannels.net:s=arc-2022:i=1") X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 2C9EF1400A5 X-Stat-Signature: gxk4613f3mmh549c95b1ewy3wmjskmis X-HE-Tag: 1655220484-594048 X-Bogosity: Ham, tests=bogofilter, spamicity=0.115196, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: >> memory_tier_lock isn't held to call register_memory_tier() in this >> patch. That will cause confusion. > >will this help to explain this better >modified mm/memory-tiers.c >@@ -151,6 +151,11 @@ static void insert_memory_tier(struct memory_tier *memtier) > struct list_head *ent; > struct memory_tier *tmp_memtier; > >+ if (IS_ENABLED(CONFIG_DEBUG_VM) && !mutex_is_locked(&memory_tier_lock)) { >+ WARN_ON_ONCE(1); >+ return; >+ } Why not just use lockdep here instead?