From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BD88D3C92E for ; Sat, 19 Oct 2024 22:46:17 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0EE736B0093; Sat, 19 Oct 2024 18:46:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 09F1A6B0095; Sat, 19 Oct 2024 18:46:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E5B216B0096; Sat, 19 Oct 2024 18:46:16 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id C3B3D6B0093 for ; Sat, 19 Oct 2024 18:46:16 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id BD36980E5D for ; Sat, 19 Oct 2024 22:46:04 +0000 (UTC) X-FDA: 82691836374.10.F1E0D3D Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf20.hostedemail.com (Postfix) with ESMTP id 22FA31C0020 for ; Sat, 19 Oct 2024 22:45:58 +0000 (UTC) Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="raBET/eq"; spf=pass (imf20.hostedemail.com: domain of mcgrof@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=mcgrof@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1729377826; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=iHZrlvphzEK5suDumbASFk80vJ39P3mMNbLKT/LkPU0=; b=6l+FtkD3stIOyR7jDYua25Zh7ICUkSO5+0ngnDefj2e79EpPGxCxwGmHYAQGeR+Gks+PvO URE3TU6EpJKEbI4nscECt3w2G9cbdbxN92G8tn7PqDdUTey4gpK0jtAkYqHoy32eZng4oz jEvcwFDSOkiJWNziY7jjO3oYEsJZWA8= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1729377826; a=rsa-sha256; cv=none; b=Vabv94su4bnyOAJTNPM5w11JrtqePfUwqnEdj9ZQAQaOnsYQfElCB1q3/zMZTixiA6iCOq oyhFyP50ZJDrYj39AWHSkFJxugDZJDO1QjmUMHg3pOiY/u3HTrr6eIsTm91MjduVDD3H4N OhJ+vTAoUIsCW70L0GhyieB5ZAfjf7Y= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b="raBET/eq"; spf=pass (imf20.hostedemail.com: domain of mcgrof@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=mcgrof@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id BF9575C5444; Sat, 19 Oct 2024 22:46:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4A187C4CEC5; Sat, 19 Oct 2024 22:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729377972; bh=cD5eaMzUFo7t+XYDnFM25WIUwCFcdwXaz1SfpP4a6SE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=raBET/eqnMHymvQ7ghoiJNJzhJfHKuWETI4KcodqrLn6OQ/Y9CKtRyA2t4EAlqgdL hZ8GXfGOFi/KBP9oOEyOznfd0G9uHgQFOCCAyoXDyjtw5nXygFTG2CrK0T0RFUBMS3 dw6lBjU8rrQg3O+nhowKfheReV2QdNr7rWdr90u1jL/xItyfqX/Q3Me8KZXxc+SLgs Bgsl1ciX2BowyzgKq/taZpeBj4IacVWutv5wVHimbHiaNsgZE0UEMAbBKocO0BFYoV nD2awtEWshprtgJwrLo1F7dN4Asn2HkQ91l7gW0Dv7NafPgx9Qm2IawXuSLgLc1IAt hvIMZRfR3Mm9A== Date: Sat, 19 Oct 2024 15:46:09 -0700 From: Luis Chamberlain To: Mike Rapoport Cc: Andrew Morton , Andreas Larsson , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Brian Cain , Catalin Marinas , Christoph Hellwig , Christophe Leroy , Dave Hansen , Dinh Nguyen , Geert Uytterhoeven , Guo Ren , Helge Deller , Huacai Chen , Ingo Molnar , Johannes Berg , John Paul Adrian Glaubitz , Kent Overstreet , "Liam R. Howlett" , Mark Rutland , Masami Hiramatsu , Matt Turner , Max Filippov , Michael Ellerman , Michal Simek , Oleg Nesterov , Palmer Dabbelt , Peter Zijlstra , Richard Weinberger , Russell King , Song Liu , Stafford Horne , Steven Rostedt , Suren Baghdasaryan , Thomas Bogendoerfer , Thomas Gleixner , Uladzislau Rezki , Vineet Gupta , Will Deacon , bpf@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-trace-kernel@vger.kernel.org, linux-um@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, sparclinux@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v6 7/8] execmem: add support for cache of large ROX pages Message-ID: References: <20241016122424.1655560-1-rppt@kernel.org> <20241016122424.1655560-8-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241016122424.1655560-8-rppt@kernel.org> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 22FA31C0020 X-Stat-Signature: jgyg71gxrkstd15wkfr7y66eqyuuk5f3 X-HE-Tag: 1729377958-357467 X-HE-Meta: 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 xWNTuu0R +oiatLuFZNiqJRB96pgpPhuzP0b4VvjJq3MsXUEOQ4Q2WxQeX97Y9IBUviUo1AWSsWw5Iu0+RDfg5CVXftBii5+YckRkGWRIdg7KzWd8zQwwweY2sf8o3pHD7j3/M9DCttm8hm/YNNc+n+gaM8zJdlnMnUp8fCLxVvgOKuJvPJCG5mDvzpc8jEIUZhYARKombuxUt6mxvUeuN0wJvFCvNnbmWYugjIxskyrsZ+O+GNRNQOqg= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, 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 Wed, Oct 16, 2024 at 03:24:23PM +0300, Mike Rapoport wrote: > From: "Mike Rapoport (Microsoft)" > > Using large pages to map text areas reduces iTLB pressure and improves > performance. > > Extend execmem_alloc() with an ability to use huge pages with ROX > permissions as a cache for smaller allocations. > > To populate the cache, a writable large page is allocated from vmalloc with > VM_ALLOW_HUGE_VMAP, filled with invalid instructions and then remapped as > ROX. > > The direct map alias of that large page is exculded from the direct map. > > Portions of that large page are handed out to execmem_alloc() callers > without any changes to the permissions. > > When the memory is freed with execmem_free() it is invalidated again so > that it won't contain stale instructions. > > An architecture has to implement execmem_fill_trapping_insns() callback > and select ARCH_HAS_EXECMEM_ROX configuration option to be able to use > the ROX cache. > > The cache is enabled on per-range basis when an architecture sets > EXECMEM_ROX_CACHE flag in definition of an execmem_range. > > Signed-off-by: Mike Rapoport (Microsoft) Reviewed-by: Luis Chamberlain Luis