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 X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FE9FC2B9F4 for ; Tue, 15 Jun 2021 02:44:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72DEE613FA for ; Tue, 15 Jun 2021 02:44:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230268AbhFOCqH (ORCPT ); Mon, 14 Jun 2021 22:46:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48218 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229811AbhFOCqD (ORCPT ); Mon, 14 Jun 2021 22:46:03 -0400 Received: from mail-io1-xd35.google.com (mail-io1-xd35.google.com [IPv6:2607:f8b0:4864:20::d35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33C2BC061574 for ; Mon, 14 Jun 2021 19:43:59 -0700 (PDT) Received: by mail-io1-xd35.google.com with SMTP id q3so18567404iop.11 for ; Mon, 14 Jun 2021 19:43:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axtens.net; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=l3K1BTqaM5pKy65dpCEo3lZI1RCD2stLd5UR2x4SDMk=; b=X0nswPKSD51xx5SUUNgPTOxx9Nzx2H96D/YduRYRZHo+ejqCQzThCbpTVUia8QeV9R HdIR5kd9RP86hki3k4UkBoiYhfysqZ1n0rn+upB0o0TRnfoK96DT08O5/uKpVd6JcNjt W/u6S+e7PCOUhEJSpkXQzLSmHd4ODdHjB47m8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=l3K1BTqaM5pKy65dpCEo3lZI1RCD2stLd5UR2x4SDMk=; b=jg4ikFP0Xo5349yBzR2kTZvT8Cl4Ai/MyhpLD5ePVY8DQbbhXYR4lc4+9jRHalNN4k 3q54AIPTHRVmgmT/VmrZKgacXI1N4jcuX6bM7vtZ/ZQai5S4o2J4MHPs9JIAs6aRrc6C 4wDjhdKhNcKpL9SbXPUUvkrhPNVMHLUzUe9cbabZtC8+jbGWRZHNSkaxzI40Wh5GoHCu pWe11OMLUJ7RUgZ39EXKOyQ0thMLon6dSRpYMeogaR2QLwlxpd529KNAgR31UZYsq9WL md/Kkm4OfRF+d0uBOFDUiLlx/qiYBjUllA/JTSopHzj+uegU+lBH17/wFvycEp/PDC3t DubQ== X-Gm-Message-State: AOAM533UwrwZYnVk6cpImiJk1w+/O74XXeK4woZXZ+G13Pjw8r6E6rVE 8F5v8GwIm5GjyqwPyPvJ4ygYgdXBllfd1Q== X-Google-Smtp-Source: ABdhPJw7o9IChYHT/R02LwCZbPFFEfQ7b/20+CtiE7nlvaJ6m/AvsWXKO7fqTTME6tiaz6HvSr0q9g== X-Received: by 2002:a63:5d52:: with SMTP id o18mr19853904pgm.440.1623721647575; Mon, 14 Jun 2021 18:47:27 -0700 (PDT) Received: from localhost ([203.206.29.204]) by smtp.gmail.com with ESMTPSA id n6sm14378524pgm.79.2021.06.14.18.47.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Jun 2021 18:47:27 -0700 (PDT) From: Daniel Axtens To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, kasan-dev@googlegroups.com, christophe.leroy@csgroup.eu, aneesh.kumar@linux.ibm.com, bsingharora@gmail.com Cc: elver@google.com, Daniel Axtens Subject: [PATCH v12 4/6] kasan: Document support on 32-bit powerpc Date: Tue, 15 Jun 2021 11:47:03 +1000 Message-Id: <20210615014705.2234866-5-dja@axtens.net> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210615014705.2234866-1-dja@axtens.net> References: <20210615014705.2234866-1-dja@axtens.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org KASAN is supported on 32-bit powerpc and the docs should reflect this. Suggested-by: Christophe Leroy Reviewed-by: Christophe Leroy Signed-off-by: Daniel Axtens --- Documentation/dev-tools/kasan.rst | 8 ++++++-- Documentation/powerpc/kasan.txt | 12 ++++++++++++ 2 files changed, 18 insertions(+), 2 deletions(-) create mode 100644 Documentation/powerpc/kasan.txt diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index 83ec4a556c19..05d2d428a332 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -36,7 +36,8 @@ Both software KASAN modes work with SLUB and SLAB memory allocators, while the hardware tag-based KASAN currently only supports SLUB. Currently, generic KASAN is supported for the x86_64, arm, arm64, xtensa, s390, -and riscv architectures, and tag-based KASAN modes are supported only for arm64. +and riscv architectures. It is also supported on 32-bit powerpc kernels. +Tag-based KASAN modes are supported only for arm64. Usage ----- @@ -343,7 +344,10 @@ CONFIG_KASAN_VMALLOC With ``CONFIG_KASAN_VMALLOC``, KASAN can cover vmalloc space at the cost of greater memory usage. Currently, this is supported on x86, -riscv, s390, and powerpc. +riscv, s390, and 32-bit powerpc. + +It is optional, except on 32-bit powerpc kernels with module support, +where it is required. This works by hooking into vmalloc and vmap and dynamically allocating real shadow memory to back the mappings. diff --git a/Documentation/powerpc/kasan.txt b/Documentation/powerpc/kasan.txt new file mode 100644 index 000000000000..26bb0e8bb18c --- /dev/null +++ b/Documentation/powerpc/kasan.txt @@ -0,0 +1,12 @@ +KASAN is supported on powerpc on 32-bit only. + +32 bit support +============== + +KASAN is supported on both hash and nohash MMUs on 32-bit. + +The shadow area sits at the top of the kernel virtual memory space above the +fixmap area and occupies one eighth of the total kernel virtual memory space. + +Instrumentation of the vmalloc area is optional, unless built with modules, +in which case it is required. -- 2.27.0