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X-CSE-ConnectionGUID: OroI7habT2+ljz3vmKyEkw== X-CSE-MsgGUID: PobEiheiSRC+XOt89ekGbQ== X-IronPort-AV: E=McAfee;i="6800,10657,11870"; a="86902136" X-IronPort-AV: E=Sophos;i="6.25,216,1779174000"; d="scan'208";a="86902136" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Aug 2026 08:25:18 -0700 X-CSE-ConnectionGUID: VjWgQZaeSp21nrem+KsjHA== X-CSE-MsgGUID: jVvUXN5AQwCtCdJSxx46ng== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,216,1779174000"; d="scan'208";a="263674064" Received: from aschende-mobl.amr.corp.intel.com (HELO [10.125.110.41]) ([10.125.110.41]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Aug 2026 08:25:18 -0700 Message-ID: Date: Mon, 10 Aug 2026 08:25:16 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 3/5] mm: Add RCU-based VMA lookup helper that waits for writers To: "Lorenzo Stoakes (ARM)" , Suren Baghdasaryan Cc: Matthew Wilcox , akpm@linux-foundation.org, dave.hansen@linux.intel.com, Liam.Howlett@oracle.com, david@kernel.org, shakeel.butt@linux.dev, vbabka@kernel.org, jannh@google.com, aliceryhl@google.com, arve@android.com, cmllamas@google.com, christian@brauner.io, tkjos@android.com, dsahern@kernel.org, davem@davemloft.net, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org References: <20260806200548.3124802-1-surenb@google.com> <20260806200548.3124802-4-surenb@google.com> Content-Language: en-US From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 70E781A0003 X-Stat-Signature: 8ciznyocujnswbuuew1nnf4au717xp67 X-HE-Tag: 1786375519-480104 X-HE-Meta: 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 +BVkV+4Q lGLe0U7We36i9w6tuI0jfeOlYnVgYv+xlB9/hMaU4thWHpRxKtQTn8iLH5+LgwIG2F1oM7yBLXsHkRaeo2P4oxDugSIfMCcFrCC64ZGo7l3ew4ZOVaz8ZdBK3dj5ufjZm6oldra4kIkj7nFOAkZJbb3cV797X58C+U85jijSE+h8gLKSkWuuIpYwGz6fg15xHIlOO9WxU/SeeerX19Y+JLIaUofg+LNCm8iYS+aXeQBA0MG00q1S4uGf+ZmGxr7RGdA9wkmY1UXjIE1cbl3PQoYSq9w== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/10/26 03:24, Lorenzo Stoakes (ARM) wrote: > Yeah I wonder about the value of this. Dave can write all this up when he makes > the change to use this in the relevant shadow stack (I think it was?) code. > > Having it here when just adding the function is not really helpful I don't think. Yeah, all the analysis and chit chat needs to get moved to the place where it is used (if it's even possible), not here.