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Tue, 28 Jul 2026 21:52:57 -0700 (PDT) Received: from google.com ([2a00:79e0:2031:6:65c1:52a3:f6d3:37dc]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2d022c2dfb1sm4915735ad.72.2026.07.28.21.52.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Jul 2026 21:52:57 -0700 (PDT) Date: Wed, 29 Jul 2026 13:52:53 +0900 From: Sergey Senozhatsky To: Richard Chang Cc: Andrew Morton , Minchan Kim , Sergey Senozhatsky , Martin Liu , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/zsmalloc: fix release order of locks in zs_page_migrate() Message-ID: References: <20260728055333.421080-1-richardycc@google.com> <20260728111509.7662e385aea0b055d2066e1f@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On (26/07/29 12:46), Richard Chang wrote: > On Wed, Jul 29, 2026 at 2:15 AM Andrew Morton wrote: > > > > Thanks. > > > > Does this actually fix a lockdep splat? If so, is a link available? > > > > No, this does not fix an active lockdep splat or a reported runtime deadlock. > It is just a code hygiene to release locks in LIFO order. Right, surprisingly enough lockdep was never unhappy with the original code (I run tests with CONFIG_PROVE_LOCKING=y.)