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 C5639C001B1 for ; Sat, 17 Jun 2023 16:38:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2A8ED6B0072; Sat, 17 Jun 2023 12:38:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 233168E0002; Sat, 17 Jun 2023 12:38:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0D1F98E0001; Sat, 17 Jun 2023 12:38:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id F2C666B0072 for ; Sat, 17 Jun 2023 12:38:35 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id BCE431401D3 for ; Sat, 17 Jun 2023 16:38:35 +0000 (UTC) X-FDA: 80912798190.15.E83BBB2 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf29.hostedemail.com (Postfix) with ESMTP id D18A7120005 for ; Sat, 17 Jun 2023 16:38:33 +0000 (UTC) Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=q5TvC7wX; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf29.hostedemail.com: domain of song@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=song@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1687019914; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=wsV5PAOYMtSK534qTONYBGMJADMTf/thu6AVR5VKWFg=; b=uT04JrtRR6ZeaCMZICf6LtIsSGNQOnt+8UOj4faAsZqxFOYJnCprdUh0rit/ZspTpBvmV7 6/i4+Tx7KKr3Dtjb6C8WlTufNVbVlfimDs7s3KWv4Go4/irXH+AJ5OIlZpyFpLfNksUNmO za48EMX7BXmkq379sk4ExNxMFxQyxfY= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=q5TvC7wX; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf29.hostedemail.com: domain of song@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=song@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1687019914; a=rsa-sha256; cv=none; b=w/bFhbVmSyWU4QPor9FvEuTOfxqmwYHkKxu0AzcQESUKB9M+3ZyOXxN7RQFzs44Sk7DfQD oKy9qqa7LNpcVeDaD/p6VV2g/Okjq3SCy42PY4taI6vmVJNSJhm9FkIDq1qT3kw6O4wzQx sbgUUd5WvGtUgyAjEOJHVxWYzS4vFXA= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CB04B61252 for ; Sat, 17 Jun 2023 16:38:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCB0CC433AB for ; Sat, 17 Jun 2023 16:38:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687019911; bh=wsV5PAOYMtSK534qTONYBGMJADMTf/thu6AVR5VKWFg=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=q5TvC7wXcesBdrAtVwBAqlybicfQ3l31tWhe47gCHoheDPlgSrgt59SLSMZIhYDmm jGSI/AbGdyvh5m2k3AnGCSYg1w5Ip7D6pqCyW2WpiRZOEAGiOwo2Hmd+1j6rAUprE/ b4HC/Njwt5Mk8bqvMnWE6kMHhKXtbhBU8/LPHAhQqUf6bNYjoID11JcNvnbHR/Wty1 Ci4aW7m3E0aYzqV5URi12B3tlQTJav9/V3UGVH6RUi6w1dQdJ06xsBzhXtuLm5kC4A 9lTOU3FN61E41TP3c36eHFu7PswdRbNKM83MrM077JEeujQ0StC2gBK9V8FMll8Kgo IyVxt6UshhCrg== Received: by mail-lf1-f43.google.com with SMTP id 2adb3069b0e04-4f841b7a697so2303491e87.3 for ; Sat, 17 Jun 2023 09:38:31 -0700 (PDT) X-Gm-Message-State: AC+VfDwPlM7vpv7OFoMRyqin5D1veAIcRIA8m+hEz6aSIF/BGfrrd7vd IgtHnFn4IT7Jq1AVtNlNbP4jMVJJN7xW2/NpsV8= X-Google-Smtp-Source: ACHHUZ7/x1kYUhYXMtUENPjhDtD48HKOo5oy2K5VqpfigImzwjTDz7CrLzlDpzPNd4SA2zOD7D4teoP7FVQzMuuaU40= X-Received: by 2002:ac2:5bd1:0:b0:4eb:42b7:8c18 with SMTP id u17-20020ac25bd1000000b004eb42b78c18mr3005243lfn.53.1687019909491; Sat, 17 Jun 2023 09:38:29 -0700 (PDT) MIME-Version: 1.0 References: <20230616085038.4121892-1-rppt@kernel.org> <20230616085038.4121892-8-rppt@kernel.org> <20230617065759.GT52412@kernel.org> In-Reply-To: From: Song Liu Date: Sat, 17 Jun 2023 09:38:17 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 07/12] arm64, execmem: extend execmem_params for generated code definitions To: Kent Overstreet Cc: Mike Rapoport , linux-kernel@vger.kernel.org, Andrew Morton , Catalin Marinas , Christophe Leroy , "David S. Miller" , Dinh Nguyen , Heiko Carstens , Helge Deller , Huacai Chen , Luis Chamberlain , Mark Rutland , Michael Ellerman , Nadav Amit , "Naveen N. Rao" , Palmer Dabbelt , Puranjay Mohan , Rick Edgecombe , Russell King , Steven Rostedt , Thomas Bogendoerfer , Thomas Gleixner , Will Deacon , bpf@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: D18A7120005 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: u146wz8kzbqeuh6osg8ubj3kq7wdzogy X-HE-Tag: 1687019913-200837 X-HE-Meta: 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 OS/ESxyS ZNhg0LsgmdZQBw1Z1cWlt9vBKf+bUMUaU2AYB/tgF/8BiEP+L8zdM3WirH8skjAEdh1gF65zr9K+vfSluTcJqbnvcdb2OK81+T5XkAqoNUV2+XNPItYK+eXRSo4N0KicUy74g5yB7T0ejNw607WslglqyBG+tQjHSWhh7hPAmAQ4dM1Y6fxkS2lPioHD/ay2vrzu58r4uD+79eN4jsAQlRhOMAN4pHktyJqqfxmK+Yni9UEUB1+cyTeaZwSTxapwdwgxwROFfQF5UYPdf8wMfNmPFNSTHJfk+jzOBzLRNbyjqPMMc4w7Bjbzlfd2AD2MQR3eCo0QOo6yRMAyqYrv9p7ZksgFVW6C+Tb72/ZttoPaUjsTSdgc6dA4XKUANKhQlYnqWQvq9F0MKm/flBxlsOkgxiPVQrO5LKkKhRFYndd597O+2kqcII92xdA== 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: On Sat, Jun 17, 2023 at 8:37=E2=80=AFAM Kent Overstreet wrote: > > On Sat, Jun 17, 2023 at 09:57:59AM +0300, Mike Rapoport wrote: > > > This is growing fast. :) We have 3 now: text, data, jit. And it will = be > > > 5 when we split data into rw data, ro data, ro after init data. I won= der > > > whether we should still do some type enum here. But we can revisit > > > this topic later. > > > > I don't think we'd need 5. Four at most :) > > > > I don't know yet what would be the best way to differentiate RW and RO > > data, but ro_after_init surely won't need a new type. It either will be > > allocated as RW and then the caller will have to set it RO after > > initialization is done, or it will be allocated as RO and the caller wi= ll > > have to do something like text_poke to update it. > > Perhaps ro_after_init could use the same allocation interface and share > pages with ro pages - if we just added a refcount for "this page > currently needs to be rw, module is still loading?" If we don't relax rules with read only, we will have to separate rw, ro, and ro_after_init. But we can still have page sharing: Two modules can put rw data on the same page. With text poke (ro data poke to be accurate), two modules can put ro data on the same page. > text_poke() approach wouldn't be workable, you'd have to audit and fix > all module init code in the entire kernel. Agreed. For this reason, each module has to have its own page(s) for ro_after_init data. To eventually remove VM_FLUSH_RESET_PERMS, we want ro_after_init data to share the same allocation interface. Thanks, Song