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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03594C4332F for ; Thu, 20 Oct 2022 09:07:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230182AbiJTJHn (ORCPT ); Thu, 20 Oct 2022 05:07:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbiJTJHl (ORCPT ); Thu, 20 Oct 2022 05:07:41 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D6EFA19C061 for ; Thu, 20 Oct 2022 02:07:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6E2F8B826A5 for ; Thu, 20 Oct 2022 09:07:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 162A0C433D7; Thu, 20 Oct 2022 09:07:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666256857; bh=g8NaNuEldTy+x0KzS6ZbURgaE6wc7Eaz7sRUiTtxPbs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZOEbPDQyjrMk8DtKVtEQjrZtnPaA9jR7mjW4ndxxhDb31/qw2u5uqMPOiTuX+XIp0 rhSRqyWn2Sx16hPO9bAKZMsG3bJVv33PMA+yIOVLNTtZr8y2dzz8+6li3vRnnJ6Gco wM3KBOvgNiNAl/oIVAB27d4iGH7HOilf7RHu0BE+zPtDiDYPJEncEyrnEo+0kzy5Vj YO6QidKcyVMjOuoNvYtL8E8huxxll06pOr6MXEiL1CHneVueUsqm58+9kt2tgSguJp NP5i0ejrIv/Mymksp4SAAqmCebVAo7mrYCvE4kqHjpn74F9tRBbjVmznezM91PKiUq pJlGoilJNxhbw== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1olRWY-000Buf-PN; Thu, 20 Oct 2022 10:07:34 +0100 From: Marc Zyngier To: , , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: James Morse , Suzuki K Poulose , Alexandru Elisei , Oliver Upton , Quentin Perret , Will Deacon , Fuad Tabba Subject: [PATCH 01/17] arm64: Turn kaslr_feature_override into a generic SW feature override Date: Thu, 20 Oct 2022 10:07:11 +0100 Message-Id: <20221020090727.3669908-2-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221020090727.3669908-1-maz@kernel.org> References: <20221020090727.3669908-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.cs.columbia.edu, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, oliver.upton@linux.dev, qperret@google.com, will@kernel.org, tabba@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Disabling KASLR from the command line is implemented as a feature override. Repaint it slightly so that it can further be used as more generic infrastructure for SW override purposes. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/cpufeature.h | 4 ++++ arch/arm64/kernel/cpufeature.c | 2 ++ arch/arm64/kernel/idreg-override.c | 16 ++++++---------- arch/arm64/kernel/kaslr.c | 6 +++--- 4 files changed, 15 insertions(+), 13 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index f73f11b55042..f44a7860636f 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -15,6 +15,8 @@ #define MAX_CPU_FEATURES 128 #define cpu_feature(x) KERNEL_HWCAP_ ## x +#define ARM64_SW_FEATURE_OVERRIDE_NOKASLR 0 + #ifndef __ASSEMBLY__ #include @@ -914,6 +916,8 @@ extern struct arm64_ftr_override id_aa64smfr0_override; extern struct arm64_ftr_override id_aa64isar1_override; extern struct arm64_ftr_override id_aa64isar2_override; +extern struct arm64_ftr_override arm64_sw_feature_override; + u32 get_kvm_ipa_limit(void); void dump_cpu_features(void); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 6062454a9067..a3959e9f7d55 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -620,6 +620,8 @@ struct arm64_ftr_override __ro_after_init id_aa64smfr0_override; struct arm64_ftr_override __ro_after_init id_aa64isar1_override; struct arm64_ftr_override __ro_after_init id_aa64isar2_override; +struct arm64_ftr_override arm64_sw_feature_override; + static const struct __ftr_reg_entry { u32 sys_id; struct arm64_ftr_reg *reg; diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 95133765ed29..4e8ef5e05db7 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -137,15 +137,11 @@ static const struct ftr_set_desc smfr0 __initconst = { }, }; -extern struct arm64_ftr_override kaslr_feature_override; - -static const struct ftr_set_desc kaslr __initconst = { - .name = "kaslr", -#ifdef CONFIG_RANDOMIZE_BASE - .override = &kaslr_feature_override, -#endif +static const struct ftr_set_desc sw_features __initconst = { + .name = "arm64_sw", + .override = &arm64_sw_feature_override, .fields = { - FIELD("disabled", 0, NULL), + FIELD("nokaslr", ARM64_SW_FEATURE_OVERRIDE_NOKASLR, NULL), {} }, }; @@ -157,7 +153,7 @@ static const struct ftr_set_desc * const regs[] __initconst = { &isar1, &isar2, &smfr0, - &kaslr, + &sw_features, }; static const struct { @@ -174,7 +170,7 @@ static const struct { "id_aa64isar1.api=0 id_aa64isar1.apa=0 " "id_aa64isar2.gpa3=0 id_aa64isar2.apa3=0" }, { "arm64.nomte", "id_aa64pfr1.mte=0" }, - { "nokaslr", "kaslr.disabled=1" }, + { "nokaslr", "arm64_sw.nokaslr=1" }, }; static int __init find_field(const char *cmdline, diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c index 325455d16dbc..7b39283278e5 100644 --- a/arch/arm64/kernel/kaslr.c +++ b/arch/arm64/kernel/kaslr.c @@ -23,8 +23,6 @@ u64 __ro_after_init module_alloc_base; u16 __initdata memstart_offset_seed; -struct arm64_ftr_override kaslr_feature_override __initdata; - static int __init kaslr_init(void) { u64 module_range; @@ -36,7 +34,9 @@ static int __init kaslr_init(void) */ module_alloc_base = (u64)_etext - MODULES_VSIZE; - if (kaslr_feature_override.val & kaslr_feature_override.mask & 0xf) { + if (cpuid_feature_extract_unsigned_field(arm64_sw_feature_override.val & + arm64_sw_feature_override.mask, + ARM64_SW_FEATURE_OVERRIDE_NOKASLR)) { pr_info("KASLR disabled on command line\n"); return 0; } -- 2.34.1