Received: by 2002:a05:6358:3188:b0:123:57c1:9b43 with SMTP id q8csp12117088rwd; Fri, 23 Jun 2023 01:23:04 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7lf8VoDT10lGMj++UlklpnwNJ6AZi/eeJX/phU3XjscgapSZ7S6NyQDQPrnvpBC+39GZPL X-Received: by 2002:a17:903:1207:b0:1ab:d6f:51b0 with SMTP id l7-20020a170903120700b001ab0d6f51b0mr23174198plh.18.1687508584427; Fri, 23 Jun 2023 01:23:04 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1687508584; cv=none; d=google.com; s=arc-20160816; b=EM45Jte16K57QFCjmjHJs+oBa5wp6ociS1Vq/Y6crNAaC/koYh/UQRwOX7mkom0HJH Sx0xRRPGfCpu0wvpBCLq+HT6Ae5dTeoLyjb4jWz5KOMw4Dw+xyTmCebfyNThZolwFj+i VpUxEEcbtT4x+txQQ0PSSZG6P7qf5s4FdI0lht7s99YTxYiC+qJrj9m6ZW0tFSNQ4HUO BHpMb45NmpaoUj3k9KU4KEU7N0LW/jJ9LxFC7sl8gw86fuX92ePENE2tChjj+dKeqp4a I9crGiklwTMYubI8Hqsau80X61lf/L4q3e8pyjAmTMZJPhOQEdwk39G/lfRjwjuvtHn8 HYgw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:references:in-reply-to:message-id:date:subject :cc:to:from; bh=JoKGkYgZzPdv1qxY2Tw1MfAsCqyqgX341vwV35LziNw=; b=VVbfzBr9m4gaFuJae8b3D4//z0husJBtKcIvY5SY7nlwe2sCxtj15kPPGs03QClb4/ VvKFBcFF9mWAzM3BUv3NNtt4EKghlLs51Aswj8n4hasFplufeybtuaa096mURu3WKJJE ErAxolApIKfd9ipoA/MW0hjnuSQ+/lmSByD7S3UJt1X8Um5Xnb/iwb1LMatfTkoIPzst DLqtsS3R6O0mnsuOxnhr2dP34EOVL9vHU8c4lqW7dCMMjex3Ftayh6hCCntmrdQggh/x mJJK6Qsum2psuCIJNLX9Pp8qrgpjBiWjiNWjlT035zTzE7WGqF2XkgtuKnwPK/P2OQdj GNPw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id o1-20020a170902bcc100b001b3415a07dcsi8188534pls.91.2023.06.23.01.22.50; Fri, 23 Jun 2023 01:23:04 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230217AbjFWH6L (ORCPT + 99 others); Fri, 23 Jun 2023 03:58:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230163AbjFWH6K (ORCPT ); Fri, 23 Jun 2023 03:58:10 -0400 Received: from lgeamrelo11.lge.com (lgeamrelo11.lge.com [156.147.23.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 1B9381BCC for ; Fri, 23 Jun 2023 00:58:07 -0700 (PDT) Received: from unknown (HELO lgeamrelo01.lge.com) (156.147.1.125) by 156.147.23.51 with ESMTP; 23 Jun 2023 16:58:05 +0900 X-Original-SENDERIP: 156.147.1.125 X-Original-MAILFROM: chanho.min@lge.com Received: from unknown (HELO localhost.localdomain) (10.178.31.96) by 156.147.1.125 with ESMTP; 23 Jun 2023 16:58:05 +0900 X-Original-SENDERIP: 10.178.31.96 X-Original-MAILFROM: chanho.min@lge.com From: Chanho Min To: andreyknvl@gmail.com Cc: chanho.min@lge.com, dvyukov@google.com, elver@google.com, glider@google.com, gunho.lee@lge.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ryabinin.a.a@gmail.com, vincenzo.frascino@arm.com Subject: [PATCH v2] kasan: fix mention for KASAN_HW_TAGS Date: Fri, 23 Jun 2023 16:58:05 +0900 Message-Id: <20230623075805.1630-1-chanho.min@lge.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: X-Spam-Status: No, score=-1.7 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED, RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL,SORTED_RECIPS,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch fixes description of the KASAN_HW_TAGS's memory consumption. KASAN_HW_TAGS are dependent on the HW implementation and are not reserved from system memory like shadow memory. Suggested-by: Andrey Konovalov Signed-off-by: Chanho Min --- lib/Kconfig.kasan | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index fdca89c05745..f8f9e12510b7 100644 --- a/lib/Kconfig.kasan +++ b/lib/Kconfig.kasan @@ -124,7 +124,8 @@ config KASAN_HW_TAGS Supported only on arm64 CPUs starting from ARMv8.5 and relies on Memory Tagging Extension and Top Byte Ignore. - Consumes about 1/32nd of available memory. + Does not consume memory by itself but relies on the 1/32nd of + available memory being reserved by the firmware when MTE is enabled. May potentially introduce problems related to pointer casting and comparison, as it embeds a tag into the top byte of each pointer. -- 2.17.1