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[103.168.172.200]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7d09a115aabsm281505485a.60.2025.05.30.12.36.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 May 2025 12:36:16 -0700 (PDT) Received: from phl-compute-05.internal (phl-compute-05.phl.internal [10.202.2.45]) by mailfauth.phl.internal (Postfix) with ESMTP id 115E61200043; Fri, 30 May 2025 15:36:16 -0400 (EDT) Received: from phl-mailfrontend-01 ([10.202.2.162]) by phl-compute-05.internal (MEProxy); Fri, 30 May 2025 15:36:16 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddtgddvleekjeculddtuddrgeefvddrtd dtmdcutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpggft fghnshhusghstghrihgsvgdpuffrtefokffrpgfnqfghnecuuegrihhlohhuthemuceftd dtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpeffhffvvefukfhf gggtuggjsehttdertddttddvnecuhfhrohhmpeeuohhquhhnucfhvghnghcuoegsohhquh hnrdhfvghnghesghhmrghilhdrtghomheqnecuggftrfgrthhtvghrnhephfetvdfgtdeu kedvkeeiteeiteejieehvdetheduudejvdektdekfeegvddvhedtnecuffhomhgrihhnpe hkvghrnhgvlhdrohhrghenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgr ihhlfhhrohhmpegsohhquhhnodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqd eiledvgeehtdeigedqudejjeekheehhedvqdgsohhquhhnrdhfvghngheppehgmhgrihhl rdgtohhmsehfihigmhgvrdhnrghmvgdpnhgspghrtghpthhtohepudeipdhmohguvgepsh hmthhpohhuthdprhgtphhtthhopehlohhsshhinheskhgvrhhnvghlrdhorhhgpdhrtghp thhtoheptghhrhhishhirdhstghhrhgvfhhlsehgmhgrihhlrdgtohhmpdhrtghpthhtoh epuggrkhhrsehkvghrnhgvlhdrohhrghdprhgtphhtthhopehgrhgvghhkhheslhhinhhu gihfohhunhgurghtihhonhdrohhrghdprhgtphhtthhopehrrghfrggvlheskhgvrhhnvg hlrdhorhhgpdhrtghpthhtohepohhjvggurgeskhgvrhhnvghlrdhorhhgpdhrtghpthht oheprghlvgigrdhgrgihnhhorhesghhmrghilhdrtghomhdprhgtphhtthhopehgrghrhi esghgrrhihghhuohdrnhgvthdprhgtphhtthhopegsjhhorhhnfegpghhhsehprhhothho nhhmrghilhdrtghomh X-ME-Proxy: Feedback-ID: iad51458e:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 30 May 2025 15:36:15 -0400 (EDT) Date: Fri, 30 May 2025 12:36:14 -0700 From: Boqun Feng To: Benno Lossin Cc: Christian Schrefl , Danilo Krummrich , gregkh@linuxfoundation.org, rafael@kernel.org, ojeda@kernel.org, alex.gaynor@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, a.hindborg@kernel.org, aliceryhl@google.com, tmgross@umich.edu, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/7] misc device: support device drivers Message-ID: References: <20250530142447.166524-1-dakr@kernel.org> <9e0acb35-7d10-4a8e-b5c6-968d1310146b@gmail.com> <96891e54-8614-4f98-8a98-ad90f18c8e43@gmail.com> Precedence: bulk X-Mailing-List: rust-for-linux@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: On Fri, May 30, 2025 at 12:35:21PM -0700, Boqun Feng wrote: > On Fri, May 30, 2025 at 09:24:28PM +0200, Benno Lossin wrote: > > On Fri May 30, 2025 at 7:29 PM CEST, Christian Schrefl wrote: > > > On 30.05.25 6:37 PM, Christian Schrefl wrote: > > >> On 30.05.25 4:24 PM, Danilo Krummrich wrote: > > >>> This patch series adds support for device drivers to the misc device > > >>> abstraction. > > >>> > > >>> For design details, please see: > > >>> * patch 5 "rust: miscdevice: properly support device drivers" > > >>> * patch 6 "rust: miscdevice: expose the parent device as &Device" > > >>> > > >>> This patch series depends on the pin-init series from Benno [1] as well as on > > >>> the misc device series from Christian [2], with UnsafePinned replaced with > > >>> Opaque, as suggested by Alice, since UnsafePinned may still take a while to > > >>> land. > > Maybe I'm missing something, but don't we have our own version of > `UnsafePinned` [1] which can be replaced once Rust upstream has the > `UnsafePinned` stabilized. I don't see any discussion about abandoning > that effort. > Missing the link.. [1]: https://lore.kernel.org/rust-for-linux/20250430-rust_unsafe_pinned-v2-0-fc8617a74024@gmail.com/ > Regards, > Boqun > > > >> > > >> If you want I can send out a new version using `Opaque`. > > >> > > >> We could also add a type alias like: > > >> > > >> type UnsafePinned = Opaque; > > > > > > I forgot that Opaque doesn't drop, this would not be quite as simple, > > > but with a newtype with a `Drop` impl it should be possible. > > > > That's one issue another is that `Opaque` also allows uninitialized > > memory and (if the upstream one isn't changed) also modifies the > > behavior of shared references. I don't think we should name it > > `UnsafePinned` if it doesn't guarantee the same thing as the upstream > > one. > > > > --- > > Cheers, > > Benno