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[35.245.46.111]) by smtp.gmail.com with ESMTPSA id ada2fe7eead31-7cc9236f63csm803396137.5.2026.10.20.16.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Oct 2026 16:13:43 -0700 (PDT) Date: Tue, 20 Oct 2026 19:13:42 -0400 From: Willem de Bruijn To: "Michael S. Tsirkin" , Willem de Bruijn Cc: linux-kernel@vger.kernel.org, Chris Arges , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Phil Sutter , Jason Wang , =?UTF-8?B?RXVnZW5pbyBQw6lyZXo=?= , Xuan Zhuo , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, virtualization@lists.linux.dev, Max Krasnyansky , Rusty Russell , Jonathan Corbet , Shuah Khan , Randy Dunlap , Simon Horman , linux-doc@vger.kernel.org Message-ID: In-Reply-To: <20261020165610-mutt-send-email-mst@kernel.org> References: <6f23c55c6eba3e3ec6b2c7e3a80728a326ed58af.1792411304.git.mst@redhat.com> <20261020165610-mutt-send-email-mst@kernel.org> Subject: Re: [PATCH net v3 6/8] net: add a sysctl to opt out of virtio net hdr checksum validation X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Michael S. Tsirkin wrote: > On Tue, Oct 20, 2026 at 03:54:23PM -0400, Willem de Bruijn wrote: > > > +/* > > > + * Protects changes to virtio_net_hdr_csum_check_disabled_key and each > > > + * net->core.sysctl_virtio_net_hdr_csum_check. Readers don't use a lock. > > > > it appears that they take the mutex_lock below > > Some of them? But > virtio_net_hdr_csum_check_disabled doesn't, that's the point, right? > Yes, but the statement is then too absolute: _some_ (or most) readers don't use a lock.