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[209.85.218.45]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b734fb12d55sm1413794766b.33.2025.11.18.11.22.44 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 18 Nov 2025 11:22:44 -0800 (PST) Received: by mail-ej1-f45.google.com with SMTP id a640c23a62f3a-b735e278fa1so888750966b.0 for ; Tue, 18 Nov 2025 11:22:44 -0800 (PST) X-Forwarded-Encrypted: i=1; AJvYcCWm7H/b9VU9hJ8pHxvWY61cUsvFlQEVE1wQLT9+q+oihInUXCb7LADyCYHK4XKJB1Qn2jmP6bN1@lists.linux.dev X-Received: by 2002:a17:907:7f08:b0:b73:9a71:13bb with SMTP id a640c23a62f3a-b739a711bbfmr1105968666b.32.1763493763746; Tue, 18 Nov 2025 11:22:43 -0800 (PST) Precedence: bulk X-Mailing-List: ksummit@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <58fd478f408a34b578ee8d949c5c4b4da4d4f41d.camel@HansenPartnership.com> <20251118141720.11c8d4d6@gandalf.local.home> In-Reply-To: <20251118141720.11c8d4d6@gandalf.local.home> From: Linus Torvalds Date: Tue, 18 Nov 2025 11:22:27 -0800 X-Gmail-Original-Message-ID: X-Gm-Features: AWmQ_bmsWPgGv9cNVjLyQ0s9ppWaVS135_rInJWtZnsNiDd5zgRakkeyeIBUpm8 Message-ID: Subject: Re: Clarifying confusion of our variable placement rules caused by cleanup.h To: Steven Rostedt Cc: Bart Van Assche , James Bottomley , ksummit@lists.linux.dev, Dan Williams , linux-kernel , Dan Carpenter Content-Type: text/plain; charset="UTF-8" On Tue, 18 Nov 2025 at 11:16, Steven Rostedt wrote: > > I've been doing the above, and was even going to recommend it to James. But > if it is preferred to declare the __free() variables where they are > allocated, I'd be much happier. I'm not going to make some hard rule that "it's preferred", but I think it's simpler and clearer, and I would not want to discourage it. That said, I *do* want to discourage the rash of mindless conversions. I do think th is is a situation where people should pick the more readable version when writing code, *not* a "let's convert existing code that isn't being otherwise modified" situation. And your example of > struct foo *var __free(kfree) = NULL; > > if (ret < 0) > return -ERROR; > > [ several more error exits ] > > var = kmalloc(..); is exactly where I do think that just moving the declaration down does actually make code sufficiently better that it then outweighs the "now you have the variable declarations in random places". Because I really feel like the whole "__free(kfree) = NULL" thing doesn't make sense on its own. It really only makes sense when paired with the "kmalloc()". And _that_ is why they go together. But again: I don't want to make this some kind of hard rule, and I think it should be done judiciously and with taste, not some kind of crazy conversion thing. Linus