From patchwork Tue Jan 23 14:53:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 13527537 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C846DC47DDF for ; Tue, 23 Jan 2024 14:55:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Message-ID: References:Mime-Version:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=HIJMhfIF8ruJN5x4e5a/t1xakwdnrj4BT6Re2+spWYw=; b=Nm2274OtYBozUx2tXn7zSVV6/v Go/5cbSRJCbx3k8XaRUeHovkf+Wn0a+Bq8xZyOPIlnBv2eol2EKEyUgiOwLv4wPmmuGbOptmhxVf4 A5RKh2cmTFFtn6/3NYzDOQjl8r0+KUEJhXcjYV9An6zYoifgV6GTX5lPaewS/qGsGPzGXfQStgqNt /Y4IZNfWFtBnUMezSrsWBPX4US2YRLxMnO87qM5+BmfxuoOU4leM6LaI9fipq8SomKZFL0jCjRJOA +STMYWWoTypAwRi2FS+BDkwKeZnlBTwmyRU5wHvySbyg0HGTUNqrFiaPy4eIVzIYETKY4ZUCIe0QP pRyP/fiQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rSIAx-00GtoZ-1Z; Tue, 23 Jan 2024 14:54:55 +0000 Received: from mail-yb1-xb49.google.com ([2607:f8b0:4864:20::b49]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rSIAl-00Gthb-2W for linux-arm-kernel@lists.infradead.org; Tue, 23 Jan 2024 14:54:45 +0000 Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-dbdb46770d7so6224489276.1 for ; Tue, 23 Jan 2024 06:54:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1706021682; x=1706626482; darn=lists.infradead.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=IrdsYyXQe3FCauN3JAkyHZXj9TK2DtbhA8RCtm550mE=; b=RHxT2ZBHI5CCqlUkyYOOvnnn8LlNoT1ZKIq0iz0sX6TitOf0A1s5GKR1S3ozmA0Tx6 heKu8Sj+5QYTLGJuMm3QvD4rEaWxEuRAduWVx67XBHmwidrlS4S9zoHOjPWSFjlnl6x1 79lPbYqPet8uZMbxM18jNoj/60SujhEg4t/9io8PxrmC+EmlY4E+0/JXfJpcG6DviBhy RbJM7lPgKaDIdKFsPWGLGMqewvUNTRaz6b4VpGncBrJIetKTANNhbEACQTKF8reMfOCM JXem5XyoI5lR5rjFvLo5J+eC8Z9u43l74J2efhDLSPiZkOd/FyO5KUxaGNoHV8aps/hE /ehw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706021682; x=1706626482; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=IrdsYyXQe3FCauN3JAkyHZXj9TK2DtbhA8RCtm550mE=; b=qOeQuqPfkxFR/VPlNjfrWZCClvOLtxjGxd+TjjL07UEDWB8Gpy7mxvEm2zk2apoCQe Ab2MWD95ocUQk3441uYy9sSPqNP+nIvJA7JTwHIqHdcXnFXzn3jtBZHcqS13f6Dm30UI bOI0lkFB57utlx/3tpUyqvIuRrxG3evVpWHFTUIhR1Go61E7kAVjB8y7xW/JLcC3yqTX 618vVH60cMuzN8fuGEDdvPAe9eR2AsrOFycN8zIPao/uSlrtXmO5+JS7GTT5cRPkHU5j vRB95jSj1UOIDNdJMP3tDqPsyi9mi5jQ9OVbcfKiZmaOu2tVCqO6/dvN7OsgNSDqg/RY 1E2A== X-Gm-Message-State: AOJu0YxolPMCJQ2PtIOYVi+DIoJ/1ZeQENmazkTtgSzf6bM/cQ7EgJM2 I2ZnsmsHU/lYIK/ZOCX1paMuaZ/XdpQIwLVG7EMTWrG9wsYxz3fUjMjU9emPiCZa3ck5six+/Ms UqQ+Ofo0TMeDgutOhcSIwTvYPzPheijt9dwUcJTTTcRHKUrkfVg/MoiBy0ztZ94lxnV3YZJb27G Mk4wiNBD58e5dlXF8DytTJF7aT7ZXx+0z2UulrZD/e X-Google-Smtp-Source: AGHT+IGqQG6n2fHa07Moal/lRW0FVccLcmouerMa4NYqIIjgo5e+u7eoIF14o+GpAKNg6qomKESP6zRk X-Received: from palermo.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:118a]) (user=ardb job=sendgmr) by 2002:a05:6902:1b12:b0:db5:4766:e363 with SMTP id eh18-20020a0569021b1200b00db54766e363mr2616012ybb.6.1706021682630; Tue, 23 Jan 2024 06:54:42 -0800 (PST) Date: Tue, 23 Jan 2024 15:53:08 +0100 In-Reply-To: <20240123145258.1462979-52-ardb+git@google.com> Mime-Version: 1.0 References: <20240123145258.1462979-52-ardb+git@google.com> X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-Developer-Signature: v=1; a=openpgp-sha256; l=3211; i=ardb@kernel.org; h=from:subject; bh=iN+q1zt4hvM4Hv4pBU7ECixAWT79q1GdhLb+jhHxr5I=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIXX9pSt907U41ezjzLvXaAVOZ78ZwpN48vIxr7T/HzbJC 16WeVrbUcrCIMbBICumyCIw+++7nacnStU6z5KFmcPKBDKEgYtTACZy4AfDX6l/Jkf23epamfnw 1zbWi7d8i9Sdon8JzbD7q9lTGzc1X4+R4dSeM2ejo6/+kCqYK3rh3NTW68+elEt2HS1+ofL9yBS lFFYA X-Mailer: git-send-email 2.43.0.429.g432eaa2c6b-goog Message-ID: <20240123145258.1462979-61-ardb+git@google.com> Subject: [PATCH v7 09/50] arm64: kernel: Don't rely on objcopy to make code under pi/ __init From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: Ard Biesheuvel , Catalin Marinas , Will Deacon , Marc Zyngier , Mark Rutland , Ryan Roberts , Anshuman Khandual , Kees Cook X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240123_065443_821805_F7DE782F X-CRM114-Status: GOOD ( 12.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Ard Biesheuvel We will add some code under pi/ that contains global variables that should not end up in __initdata, as they will not be writable via the initial ID map. So only rely on objcopy for making the libfdt code __init, and use explicit annotations for the rest. Signed-off-by: Ard Biesheuvel --- arch/arm64/kernel/pi/Makefile | 6 ++++-- arch/arm64/kernel/pi/kaslr_early.c | 16 +++++++++------- 2 files changed, 13 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/pi/Makefile b/arch/arm64/kernel/pi/Makefile index bc32a431fe35..2bbe866417d4 100644 --- a/arch/arm64/kernel/pi/Makefile +++ b/arch/arm64/kernel/pi/Makefile @@ -28,11 +28,13 @@ quiet_cmd_piobjcopy = $(quiet_cmd_objcopy) cmd_piobjcopy = $(cmd_objcopy) && $(obj)/relacheck $(@) $(<) $(obj)/%.pi.o: OBJCOPYFLAGS := --prefix-symbols=__pi_ \ - --remove-section=.note.gnu.property \ - --prefix-alloc-sections=.init + --remove-section=.note.gnu.property $(obj)/%.pi.o: $(obj)/%.o $(obj)/relacheck FORCE $(call if_changed,piobjcopy) +# ensure that all the lib- code ends up as __init code and data +$(obj)/lib-%.pi.o: OBJCOPYFLAGS += --prefix-alloc-sections=.init + $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE $(call if_changed_rule,cc_o_c) diff --git a/arch/arm64/kernel/pi/kaslr_early.c b/arch/arm64/kernel/pi/kaslr_early.c index b9e0bb4bc6a9..167081b30a15 100644 --- a/arch/arm64/kernel/pi/kaslr_early.c +++ b/arch/arm64/kernel/pi/kaslr_early.c @@ -17,7 +17,7 @@ #include /* taken from lib/string.c */ -static char *__strstr(const char *s1, const char *s2) +static char *__init __strstr(const char *s1, const char *s2) { size_t l1, l2; @@ -33,7 +33,7 @@ static char *__strstr(const char *s1, const char *s2) } return NULL; } -static bool cmdline_contains_nokaslr(const u8 *cmdline) +static bool __init cmdline_contains_nokaslr(const u8 *cmdline) { const u8 *str; @@ -41,7 +41,7 @@ static bool cmdline_contains_nokaslr(const u8 *cmdline) return str == cmdline || (str > cmdline && *(str - 1) == ' '); } -static bool is_kaslr_disabled_cmdline(void *fdt) +static bool __init is_kaslr_disabled_cmdline(void *fdt) { if (!IS_ENABLED(CONFIG_CMDLINE_FORCE)) { int node; @@ -67,17 +67,19 @@ static bool is_kaslr_disabled_cmdline(void *fdt) return cmdline_contains_nokaslr(CONFIG_CMDLINE); } -static u64 get_kaslr_seed(void *fdt) +static u64 __init get_kaslr_seed(void *fdt) { + static char const chosen_str[] __initconst = "chosen"; + static char const seed_str[] __initconst = "kaslr-seed"; int node, len; fdt64_t *prop; u64 ret; - node = fdt_path_offset(fdt, "/chosen"); + node = fdt_path_offset(fdt, chosen_str); if (node < 0) return 0; - prop = fdt_getprop_w(fdt, node, "kaslr-seed", &len); + prop = fdt_getprop_w(fdt, node, seed_str, &len); if (!prop || len != sizeof(u64)) return 0; @@ -86,7 +88,7 @@ static u64 get_kaslr_seed(void *fdt) return ret; } -asmlinkage u64 kaslr_early_init(void *fdt) +asmlinkage u64 __init kaslr_early_init(void *fdt) { u64 seed, range;