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Mon, 29 Dec 2025 08:15:28 -0800 (PST) Received: from [192.168.88.32] ([169.155.232.231]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-47d19346e48sm532124415e9.2.2025.12.29.08.15.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 29 Dec 2025 08:15:27 -0800 (PST) Message-ID: Date: Mon, 29 Dec 2025 17:15:26 +0100 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 net v1 1/2] octeon_ep: avoid compiler and IQ/OQ reordering To: Vimlesh Kumar , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: sedara@marvell.com, srasheed@marvell.com, hgani@marvell.com, Veerasenareddy Burru , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Satananda Burla , Abhijit Ayarekar References: <20251219072955.3048238-1-vimleshk@marvell.com> <20251219072955.3048238-2-vimleshk@marvell.com> Content-Language: en-US From: Paolo Abeni In-Reply-To: <20251219072955.3048238-2-vimleshk@marvell.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/19/25 8:29 AM, Vimlesh Kumar wrote: > Utilize READ_ONCE and WRITE_ONCE APIs for IO queue Tx/Rx > variable access to prevent compiler optimization and reordering. > Additionally, ensure IO queue OUT/IN_CNT registers are flushed > by performing a read-back after writing. Please explain why such _ONCE() annotation are required, and what could be reordered otherwise. I don't think they are needed, /P