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Miller" , Luc Van Oostenryck , Chris Li , "Paul E. McKenney" , Alexander Potapenko , Arnd Bergmann , 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 v5 15/36] srcu: Support Clang's context analysis Message-ID: <20260126213556.GQ171111@noisy.programming.kicks-ass.net> References: <20251219154418.3592607-1-elver@google.com> <20251219154418.3592607-16-elver@google.com> <8c1bbab4-4615-4518-b773-a006d1402b8b@acm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8c1bbab4-4615-4518-b773-a006d1402b8b@acm.org> X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 3BC7A1A0002 X-Stat-Signature: miyb8hjjy861z46ypiaorkimy8azz9su X-HE-Tag: 1769463377-485615 X-HE-Meta: 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 v3Saa2JW 8yRcmJVdjk0rCWH3/j5mNyv7g5Rck1PEHSGcQNtrWRnzXyNCfpyNjlNfCaTULkjU3HNiNn1Ust5IeIw9wMcNYsEpG8jDz1/G7kGivG+flNqoL7BdebcXSqh8Mz5tqyZkANus5bOK1w5ywXxEchGDEIK/lh6wk2MLQSXgD/Mht092fQY0Kb0ULFKzQCh2Xj/U2OY1FtrZOyVQEQOh04MKBwoKe+3sK6ChweeaoGsrLpavchr4HHPBP7rVnZj+4jV1AiyO9IA1CVCCwdvPRvgdoimD9BN1OYtL1U9rAkiErgh/G/kpLsWej/vSfog== 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 Mon, Jan 26, 2026 at 10:54:56AM -0800, Bart Van Assche wrote: > Has it ever been considered to add support in the clang compiler for a > variant of __must_hold() that expresses that one of two capabilities > must be held by the caller? I think that would remove the need to > annotate SRCU update-side code with __acquire_shared(ssp) and > __release_shared(ssp). Right, I think I've asked for logical operators like that. Although I think it was in the __guarded_by() clause rather than the __must_hold(). Both || and && would be nice to have ;-) Specifically, I think I asked for something like: cpumask_t cpus_allowed __guarded_by(pi_lock && rq->__lock) __guarded_shared_by(pi_lock || rq->__lock); I think Marco's suggestion was to use 'fake' locks to mimic those semantics.