From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 35340189B84; Fri, 12 Jun 2026 18:48:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781290082; cv=none; b=BspPUaQ0xwCsYAyktpdUFg4VWwh+Fzv35Kwd6vU1kE0xySazV3kogbt2fEPfFps9NVh5UJNDD7YAfGAJJbecYC8LLEWFXmn75buwR8ew5Tud6HU/mGrcIP5+d8aPSMpGLyzden2u4xY9vyU+18ykpdql+lfm6F6snePw3yHR6+Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781290082; c=relaxed/simple; bh=htPuT7tm372smVg4DmgxAuibfc4nj8Gdpe5982tY96k=; h=Content-Type:Message-ID:Date:MIME-Version:Subject:To:Cc: References:From:In-Reply-To; b=SFsGlWPSND6LvT/8tlr9ThFP6ZtS0klL64y9c4BWnp+T+4lV6Li0rGe3b783gjlgWOuRkuipt3KQIjgh3gXB2rzJEsLCJnjCrzjA/um/72xX31YU4Uj5hDQflwYLD2Dwv/AeaDpjbm4r7WK5glngMRQp1sISCSmSM4hY4KOzBxQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ElZWs6Fa; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ElZWs6Fa" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1781290081; x=1812826081; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to; bh=htPuT7tm372smVg4DmgxAuibfc4nj8Gdpe5982tY96k=; b=ElZWs6FaCYL9oKaM6Qc0ZHcqHtCkbC7irGSCn1L6Qm90LHJRxXmF+5WH RpA5h8xdUFs+oq7MTuYpmjuoh51bwucB4Ulry2Kp/BYFcUUcD26xdFp5q amT23FgmlXk0qOvoa6luSPrnF4Zf1Sjj3RAbsEsPhjF0G/fzMJCWDPZLm VDvW2ARDxkcfWEJ9GIl/ocSJeBOvJNLA7MUlY8N1yOFrN0o7XgZ389/kM OPY7Iy+FtD5nkk59sf0mU6HNijrlXXRrvdH9lHvO3GXWK3Mbq/JgSYOnZ w4uVGb4t6VUYP+2l23nc3sYSb1bXEzYgAukgN1+S29K/M/pFp+kVpt/5l A==; X-CSE-ConnectionGUID: fmkzDYL/RYW352njV6U2eg== X-CSE-MsgGUID: 1d4k+f5wRAqKP4mzq47F9g== X-IronPort-AV: E=McAfee;i="6800,10657,11815"; a="99703415" X-IronPort-AV: E=Sophos;i="6.24,201,1774335600"; d="scan'208";a="99703415" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jun 2026 11:48:01 -0700 X-CSE-ConnectionGUID: u7hVGyS+TsGIOUmWJ6QcfA== X-CSE-MsgGUID: efIcFitYTtOtCzU+B/fO/w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,201,1774335600"; d="scan'208";a="242515111" Received: from aduenasd-mobl5.amr.corp.intel.com (HELO [10.125.110.161]) ([10.125.110.161]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jun 2026 11:48:00 -0700 Content-Type: multipart/mixed; boundary="------------X9GYwTAIw7Vm1mltbbp0duDk" Message-ID: <2da031dd-4442-45b7-9515-72ffc60e8d8c@intel.com> Date: Fri, 12 Jun 2026 11:47:59 -0700 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/5] binder: Make shrinker rely solely on per-VMA lock To: Suren Baghdasaryan Cc: "Vlastimil Babka (SUSE)" , Alice Ryhl , Dave Hansen , linux-kernel@vger.kernel.org, Andrew Morton , =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOl?= =?UTF-8?Q?g?= , Carlos Llamas , Christian Brauner , David Ahern , "David S. Miller" , Greg Kroah-Hartman , "Liam R. Howlett" , linux-mm@kvack.org, Lorenzo Stoakes , netdev@vger.kernel.org, Shakeel Butt , Todd Kjos References: <20260610230409.A44D29FA@davehans-spike.ostc.intel.com> <20260610230413.D68967BC@davehans-spike.ostc.intel.com> <131c6a49-9177-418b-a653-8f13942fb8d3@kernel.org> <876077cc-db6a-4517-9d81-cdfbb43e599e@intel.com> Content-Language: en-US From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: This is a multi-part message in MIME format. --------------X9GYwTAIw7Vm1mltbbp0duDk Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/12/26 10:44, Suren Baghdasaryan wrote: >> It's not impossible, but I do think it is irrelevant. Or at least that >> the *VMA* is irrelevant in this case. binder_alloc_is_mapped()==false >> means that the binder VMA is gone. It's not in the maple tree, and it's >> not coming back. If a VMA is found, it's an impostor. > Right, but before your change we were bailing out early. With your > change we would be generating the traces and freeing the page. I think > that's a functional change. Was that your intention? Yeah, it was intentional. I think the existing behavior is buggy. It also complicates the goal of removing the mmap lock fallback. I've broken that behavior change out into a separate patch. 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