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[103.168.172.201]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7d3f9a0727bsm513818385a.108.2025.06.24.08.50.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Jun 2025 08:50:53 -0700 (PDT) Received: from phl-compute-11.internal (phl-compute-11.phl.internal [10.202.2.51]) by mailfauth.phl.internal (Postfix) with ESMTP id 33CED1200043; Tue, 24 Jun 2025 11:50:53 -0400 (EDT) Received: from phl-mailfrontend-01 ([10.202.2.162]) by phl-compute-11.internal (MEProxy); Tue, 24 Jun 2025 11:50:53 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddvgddvtddvlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpuffrtefokffrpgfnqfghnecuuegr ihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjug hrpeffhffvvefukfhfgggtuggjsehttdertddttddvnecuhfhrohhmpeeuohhquhhnucfh vghnghcuoegsohhquhhnrdhfvghnghesghhmrghilhdrtghomheqnecuggftrfgrthhtvg hrnhephedugfduffffteeutddvheeuveelvdfhleelieevtdeguefhgeeuveeiudffiedv necuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepsghoqh hunhdomhgvshhmthhprghuthhhphgvrhhsohhnrghlihhthidqieelvdeghedtieegqddu jeejkeehheehvddqsghoqhhunhdrfhgvnhhgpeepghhmrghilhdrtghomhesfhhigihmvg drnhgrmhgvpdhnsggprhgtphhtthhopedujedpmhhouggvpehsmhhtphhouhhtpdhrtghp thhtoheprghlihgtvghrhihhlhesghhoohhglhgvrdgtohhmpdhrtghpthhtohepmhgrrg hrthgvnhdrlhgrnhhkhhhorhhstheslhhinhhugidrihhnthgvlhdrtghomhdprhgtphht thhopehmrhhiphgrrhgusehkvghrnhgvlhdrohhrghdprhgtphhtthhopehtiihimhhmvg hrmhgrnhhnsehsuhhsvgdruggvpdhrtghpthhtoheprghirhhlihgvugesghhmrghilhdr tghomhdprhgtphhtthhopehsihhmohhnrgesfhhffihllhdrtghhpdhrtghpthhtohepoh hjvggurgeskhgvrhhnvghlrdhorhhgpdhrtghpthhtohepuggrkhhrsehkvghrnhgvlhdr ohhrghdprhgtphhtthhopehgrghrhiesghgrrhihghhuohdrnhgvth X-ME-Proxy: Feedback-ID: iad51458e:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 24 Jun 2025 11:50:52 -0400 (EDT) Date: Tue, 24 Jun 2025 08:50:51 -0700 From: Boqun Feng To: Alice Ryhl Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Miguel Ojeda , Danilo Krummrich , Gary Guo , =?iso-8859-1?Q?Bj=F6rn?= Roy Baron , Benno Lossin , Andreas Hindborg , Trevor Gross , dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/2] Add Opaque::cast_from Message-ID: References: <20250624-opaque-from-raw-v2-0-e4da40bdc59c@google.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20250624-opaque-from-raw-v2-0-e4da40bdc59c@google.com> On Tue, Jun 24, 2025 at 03:27:54PM +0000, Alice Ryhl wrote: > Since commit b20fbbc08a36 ("rust: check type of `$ptr` in > `container_of!`") we have enforced that the field pointer passed to > container_of! must match the declared field. This caused mismatches when > using a pointer to bindings::x for fields of type Opaque. > > This situation encourages the user to simply pass field.cast() to the > container_of! macro, but this is not great because you might > accidentally pass a *mut bindings::y when the field type is > Opaque, which would be wrong. > > To help catch this kind of mistake, add a new Opaque::cast_from that > wraps a raw pointer in Opaque without changing the inner type. Also > rename raw_get() to cast_into() for naming consistency. > > Signed-off-by: Alice Ryhl Acked-by: Boqun Feng Thanks! Regards, Boqun