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Fri, 07 Mar 2025 08:18:33 -0800 (PST) Message-ID: Date: Fri, 7 Mar 2025 09:18:32 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] fs: support filename refcount without atomics To: Mateusz Guzik , brauner@kernel.org Cc: viro@zeniv.linux.org.uk, jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, audit@vger.kernel.org References: <20250307161155.760949-1-mjguzik@gmail.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <20250307161155.760949-1-mjguzik@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit > +static inline void makeatomicname(struct filename *name) > +{ > + VFS_BUG_ON(IS_ERR_OR_NULL(name)); > + /* > + * The name can legitimately already be atomic if it was cached by audit. > + * If switching the refcount to atomic, we need not to know we are the > + * only non-atomic user. > + */ > + VFS_BUG_ON(name->owner != current && !name->is_atomic); > + /* > + * Don't bother branching, this is a store to an already dirtied cacheline. > + */ > + name->is_atomic = true; > +} Should this not depend on audit being enabled? io_uring without audit is fine. -- Jens Axboe