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AJvYcCUBejj7HmDg1/4Kyy0SUS6mNldPicmfjGzCodzGlnUE9+bkxkAF/CN0dXDeSxcHs30Vf7393Ixkeg==@kvack.org X-Gm-Message-State: AOJu0YyarJ/KbA3OZBStDmDCl9MjW1i3FQLYzmIBwyNF/nPscfL07UjK D53Ekgh6FoG7ZpIsuOkE97I9IebFfFw6hMFU24qyglQZXkorNr5c X-Gm-Gg: ASbGnctaJqVR++VxMPF+jDuSAV3LWbfMKraQGR9x9lcEjanucQ6C2+hjideRVhR+04K Eko5BEHE9sHj4T5a/Gnnf5GBJ+wNX6y/jZ+VYQkg4WRUMbsXRCQ6nDIa59J5gBjRZfzczFj08XQ JkGNtcP9cPEKhZssE1yRTz3Do8Z1pvmtklfQpvU3m22SQYS0Lbs8A148hn4pLF1RrPDBo1VIacx MXGBp7sQCNlLox7vozx7vUBdJK9Xr9NgLVfFA4VfpWR6wFQ5Q== X-Google-Smtp-Source: AGHT+IHS+B0iRGQt5BsO9uK/gwQVsu2n4QHvr0IM+ThzUnPuEmYlYuveqnSOHlPIygXmvjWWlZdwtA== X-Received: by 2002:a17:906:9d2:b0:aa6:841a:dff0 with SMTP id a640c23a62f3a-aa6841b1083mr46573466b.32.1733657227714; Sun, 08 Dec 2024 03:27:07 -0800 (PST) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-aa6260ae4e8sm520122566b.163.2024.12.08.03.27.06 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 08 Dec 2024 03:27:06 -0800 (PST) Date: Sun, 8 Dec 2024 11:27:06 +0000 From: Wei Yang To: Lorenzo Stoakes Cc: Wei Yang , Andrew Morton , "Liam R . Howlett" , Vlastimil Babka , Jann Horn , Eric Biederman , Kees Cook , Alexander Viro , Christian Brauner , Jan Kara , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/5] mm: abstract get_arg_page() stack expansion and mmap read lock Message-ID: <20241208112706.cmzyrotgnjflv47h@master> Reply-To: Wei Yang References: <5295d1c70c58e6aa63d14be68d4e1de9fa1c8e6d.1733248985.git.lorenzo.stoakes@oracle.com> <20241205001819.derfguaft7oummr6@master> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 2CE4AC0007 X-Stat-Signature: 7oedd7ebni7mdjdhacqq48od4i9cshd5 X-Rspam-User: X-HE-Tag: 1733657206-379675 X-HE-Meta: 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 ndfrM27l 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 X-Bogosity: Unsure, tests=bogofilter, spamicity=0.498834, 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, Dec 05, 2024 at 07:01:14AM +0000, Lorenzo Stoakes wrote: [...] >> >> Maybe we just leave this done in one place is enough? > >Wei, I feel like I have repeated myself about 'mathematically smallest >code' rather too many times at this stage. Doing an unsolicited drive-by >review applying this concept, which I have roundly and clearly rejected, is >not appreciated. > Hi, Lorenzo I would apologize for introducing this un-pleasant mail. Would be more thoughtful next time. >At any rate, we are checking this _before the mmap lock is acquired_. It is >also self-documenting. > >Please try to take on board the point that there are many factors when it >comes to writing kernel code, aversion to possibly generated branches being >only one of them. > Thanks for this suggestion. I am trying to be as professional as you are. In case you have other suggestions, they are welcome. -- Wei Yang Help you, Help me