From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A94BFD41C27 for ; Thu, 11 Dec 2025 11:43:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 997A26B0005; Thu, 11 Dec 2025 06:43:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 948C96B0007; Thu, 11 Dec 2025 06:43:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 836E16B0008; Thu, 11 Dec 2025 06:43:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 7278F6B0005 for ; Thu, 11 Dec 2025 06:43:29 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 28947140870 for ; Thu, 11 Dec 2025 11:43:29 +0000 (UTC) X-FDA: 84207004938.01.DCE6AAF Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf20.hostedemail.com (Postfix) with ESMTP id 77B6A1C0012 for ; Thu, 11 Dec 2025 11:43:26 +0000 (UTC) Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=gC2D4Nn6; dmarc=pass (policy=none) header.from=infradead.org; spf=none (imf20.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=peterz@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1765453407; a=rsa-sha256; cv=none; b=UBw4hJN6kuJmwNeHrCLe3SYRQh///W7HqADkFrG431dL61bY+SRN9TC2axa2owstvXLXyh RdD8QcuetOIYA7xdh+ska3VvYa3DfZOR/uzrK9DsbBrbE2ZPoJE2NU36vlmq7erQgXigbR h4CTRrhz/B0eQXgDHYzGfL/S9YjVT7g= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=gC2D4Nn6; dmarc=pass (policy=none) header.from=infradead.org; spf=none (imf20.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=peterz@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1765453407; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=uQ1t1in3MNz+55jGFoFlKgze5NqUmk6ITua4X7r2Yeo=; b=BqDE09GnKplGqG6uhXFU3FGjp3LFc1LOgROzToHchLELxw4aUU5n8XO5vfllxliYSVt3MY 1QuQnavAVjSYaTL54baosCjyMnLsYCBbUdKfF9f+DXP331hK8UN3CMj949TX+FH4e870oL gtP7vU3Z8WLeYIXzR9gcbrtEiD1Ecm4= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=uQ1t1in3MNz+55jGFoFlKgze5NqUmk6ITua4X7r2Yeo=; b=gC2D4Nn6TBsE1we2zbHDdyJ5qr 5r1+OVFGLSNem72JBqMo7iaGapPFi38ZsC431uA0Y92pG++DHkKwM6qgaxASR7JF02WkWrLSxu5+T N3/tUOuTVCAuPcWK7WW4QJzL5miwWBfBEAMHMwQukxzLV6StP8KclJid86BDcgk1KFVqtTOelz1kd TolBaeGejJh9I7Y8FKRhnFLoXnHKynMZ8pOcGBXC/qbeFfGKC2iBQZuL3ekazEAAlTEOBWJm7fS8T J3o7cDROPeRxtK+aKww43zCeRFqCeJc5r66NPdNWBNRSxKG6yWR1CYSIMJYOGRg0Rqn2M6aowIXJf TJ3ogtvg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vTf4Z-0000000EBFr-2coJ; Thu, 11 Dec 2025 11:43:03 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 29E1230301A; Thu, 11 Dec 2025 12:43:02 +0100 (CET) Date: Thu, 11 Dec 2025 12:43:02 +0100 From: Peter Zijlstra To: Marco Elver Cc: Boqun Feng , Ingo Molnar , Will Deacon , "David S. Miller" , Luc Van Oostenryck , Chris Li , "Paul E. McKenney" , Alexander Potapenko , Arnd Bergmann , Bart Van Assche , Christoph Hellwig , Dmitry Vyukov , Eric Dumazet , Frederic Weisbecker , Greg Kroah-Hartman , Herbert Xu , Ian Rogers , Jann Horn , Joel Fernandes , Johannes Berg , Jonathan Corbet , Josh Triplett , Justin Stitt , Kees Cook , Kentaro Takeda , Lukas Bulwahn , Mark Rutland , Mathieu Desnoyers , Miguel Ojeda , Nathan Chancellor , Neeraj Upadhyay , Nick Desaulniers , Steven Rostedt , Tetsuo Handa , Thomas Gleixner , Thomas Graf , Uladzislau Rezki , Waiman Long , kasan-dev@googlegroups.com, linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-security-module@vger.kernel.org, linux-sparse@vger.kernel.org, linux-wireless@vger.kernel.org, llvm@lists.linux.dev, rcu@vger.kernel.org Subject: Re: [PATCH v4 07/35] lockdep: Annotate lockdep assertions for context analysis Message-ID: <20251211114302.GC3911114@noisy.programming.kicks-ass.net> References: <20251120145835.3833031-2-elver@google.com> <20251120151033.3840508-7-elver@google.com> <20251120151033.3840508-8-elver@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251120151033.3840508-8-elver@google.com> X-Rspamd-Queue-Id: 77B6A1C0012 X-Stat-Signature: w4c35ezw9o9ehrjhiezaisjw3rpib6qa X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1765453406-117154 X-HE-Meta: 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 9Q4Jo5X3 TStS0kOEXWfyp9rJw+41IWLZc9bLX0/Hbl//Grlv84iQvTikd5R/nLmIMmjM5q2Xb4dM3ccyVdVZ1Vx9tXTt/PK2UFDv6gzp1pGGAUhoTE3M6kRnrS5HaWvSHM1A6Fqi62+Ud3DU099FsV0xt+E4KIvYbdAFnEqBk5FBLWOTbInoNuSobbWpxvxePzY9QmQsMx0vZVO2amoFuSjC5A8wa/l8SUoi8KXVtBbXXZV+VD7wJKzKiPx7wVU7VgJH+6KsdK36LKrV2ldUtPXYki9Fch0YBAR0fWy9quD9S7NCZogRJdcvGua+yrh3g9goP5M4uvnK1 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Nov 20, 2025 at 04:09:32PM +0100, Marco Elver wrote: > include/linux/lockdep.h | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h > index 67964dc4db95..2c99a6823161 100644 > --- a/include/linux/lockdep.h > +++ b/include/linux/lockdep.h > @@ -282,16 +282,16 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie); > do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0) Since I typically read patches without first reading the Changelog -- because when I read the code later, I also don't see changelogs. I must admit to getting most terribly confused here -- *again*, as I then search back to previous discussions and found I was previously also confused. As such, I think we want a comment here that explains that assume_ctx thing. It is *NOT* (as the clang naming suggests) an assertion of holding the lock (which is requires_ctx), but rather an annotation that forces the ctx to be considered held. > > #define lockdep_assert_held(l) \ > - lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD) > + do { lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD); __assume_ctx_guard(l); } while (0) > > #define lockdep_assert_not_held(l) \ > lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD) > > #define lockdep_assert_held_write(l) \ > - lockdep_assert(lockdep_is_held_type(l, 0)) > + do { lockdep_assert(lockdep_is_held_type(l, 0)); __assume_ctx_guard(l); } while (0) > > #define lockdep_assert_held_read(l) \ > - lockdep_assert(lockdep_is_held_type(l, 1)) > + do { lockdep_assert(lockdep_is_held_type(l, 1)); __assume_shared_ctx_guard(l); } while (0) > > #define lockdep_assert_held_once(l) \ > lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD) > @@ -389,10 +389,10 @@ extern int lockdep_is_held(const void *); > #define lockdep_assert(c) do { } while (0) > #define lockdep_assert_once(c) do { } while (0) > > -#define lockdep_assert_held(l) do { (void)(l); } while (0) > +#define lockdep_assert_held(l) __assume_ctx_guard(l) > #define lockdep_assert_not_held(l) do { (void)(l); } while (0) > -#define lockdep_assert_held_write(l) do { (void)(l); } while (0) > -#define lockdep_assert_held_read(l) do { (void)(l); } while (0) > +#define lockdep_assert_held_write(l) __assume_ctx_guard(l) > +#define lockdep_assert_held_read(l) __assume_shared_ctx_guard(l) > #define lockdep_assert_held_once(l) do { (void)(l); } while (0) > #define lockdep_assert_none_held_once() do { } while (0) > > -- > 2.52.0.rc1.455.g30608eb744-goog >