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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1, USER_IN_DEF_DKIM_WL 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 82E27C07E9C for ; Mon, 5 Jul 2021 15:04:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F15B61279 for ; Mon, 5 Jul 2021 15:04:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231556AbhGEPHD (ORCPT ); Mon, 5 Jul 2021 11:07:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231477AbhGEPHB (ORCPT ); Mon, 5 Jul 2021 11:07:01 -0400 Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB3C2C061574 for ; Mon, 5 Jul 2021 08:04:23 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id t14-20020a05600c198eb029020c8aac53d4so4067126wmq.1 for ; Mon, 05 Jul 2021 08:04:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=At8qjqAN8f+W2do/QMp0ecm1lFUsBPDE6HfKaXVwDro=; b=v70/7r/s5wRbr8RuYY9kFjI9ukbImPIQ/c7UM51DPMnhqQ8aGT5Y5doykcqmdROjRp tPe0aDlCtGnP2mHC1BFVc56zsN1PN2nQK8+6Yt47G0MMLUBwH+o0TcgUqcCCi2k6g/pd q/wMTzyH0JhU7XDljO1Lvb85MQH1W/VkWc0gPHu/TxP1aefn26mA9czSSMMTUKwGwka2 Lr+Sj/4BA6TbNQiACnCLr+dDBBVAGX5m0OqkkBdHdD3XfJ+vaVUgKWB+lydypAeZmrCD NjF0Zu5PLT4ihbdIqwFr/Zid9HY/ipmw778GpoNHtjrbGrf9f100X+Y9rlFxQCdSvPIf QMeA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=At8qjqAN8f+W2do/QMp0ecm1lFUsBPDE6HfKaXVwDro=; b=hHkQpFOuYKUB7A7IYF7nVXyp/F1pJzW0UVmX6VbY9U7eN1QAO+7pD14LkLdqa0a+Qe 8qj094FQbLF5maMiAzrsHbhOPuJUozC/8s9wc9uVtw2Xqdhjiy8oOkkfTnrPReEzFdH0 SD5iRc3teiqLrVjvOcwJzrvNMlEn8+g0e4K3vggeJdkPALILygX6+jMSIHh4QxB2XOXR fyes6uYahvaGLIMC/FL8PYBjAK2kzghT2RVf6XL7BrEc/k0Oe9olujkECdgxtej1uy/Z HqOCMTCnh+Ft0TsHK+qp51s7HBHVKrGabR4lR/CB9QHyQjNnBYvoF5i/MV6Rye5wYGo3 0I6A== X-Gm-Message-State: AOAM531I/Zr3Y6x/UQtL4eEDoN3fqvERGIJ+7MQrE/WmgLF+rcZr7OUp teb3x6UMhceefIAC2DFLTz8MTg== X-Google-Smtp-Source: ABdhPJwzZh/4D5yDZ6JWELeJ85BkGi++TNbYqVr3hQUWFfFvywLWOhctBGjSFPQzNDxcQe5nTQ3xAA== X-Received: by 2002:a7b:c15a:: with SMTP id z26mr15436389wmi.109.1625497462273; Mon, 05 Jul 2021 08:04:22 -0700 (PDT) Received: from elver.google.com ([2a00:79e0:15:13:3207:330f:6162:ea09]) by smtp.gmail.com with ESMTPSA id t9sm14493333wmq.14.2021.07.05.08.04.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jul 2021 08:04:21 -0700 (PDT) Date: Mon, 5 Jul 2021 17:04:16 +0200 From: Marco Elver To: Kefeng Wang Cc: Catalin Marinas , Will Deacon , Andrey Ryabinin , Andrey Konovalov , Dmitry Vyukov , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, Daniel Axtens Subject: Re: [PATCH -next 3/3] kasan: arm64: Fix pcpu_page_first_chunk crash with KASAN_VMALLOC Message-ID: References: <20210705111453.164230-1-wangkefeng.wang@huawei.com> <20210705111453.164230-4-wangkefeng.wang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210705111453.164230-4-wangkefeng.wang@huawei.com> User-Agent: Mutt/2.0.5 (2021-01-21) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 05, 2021 at 07:14PM +0800, Kefeng Wang wrote: [...] > +#ifdef CONFIG_KASAN_VMALLOC > +void __init __weak kasan_populate_early_vm_area_shadow(void *start, > + unsigned long size) This should probably not be __weak, otherwise you now have 2 __weak functions. > +{ > + unsigned long shadow_start, shadow_end; > + > + if (!is_vmalloc_or_module_addr(start)) > + return; > + > + shadow_start = (unsigned long)kasan_mem_to_shadow(start); > + shadow_start = ALIGN_DOWN(shadow_start, PAGE_SIZE); > + shadow_end = (unsigned long)kasan_mem_to_shadow(start + size); > + shadow_end = ALIGN(shadow_end, PAGE_SIZE); > + kasan_map_populate(shadow_start, shadow_end, > + early_pfn_to_nid(virt_to_pfn(start))); > +} > +#endif This function looks quite generic -- would any of this also apply to other architectures? I see that ppc and sparc at least also define CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK. > void __init kasan_init(void) > { > kasan_init_shadow(); > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > index 5310e217bd74..79d3895b0240 100644 > --- a/include/linux/kasan.h > +++ b/include/linux/kasan.h > @@ -49,6 +49,8 @@ extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D]; > int kasan_populate_early_shadow(const void *shadow_start, > const void *shadow_end); > > +void kasan_populate_early_vm_area_shadow(void *start, unsigned long size); > + > static inline void *kasan_mem_to_shadow(const void *addr) > { > return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT) > diff --git a/mm/kasan/init.c b/mm/kasan/init.c > index cc64ed6858c6..d39577d088a1 100644 > --- a/mm/kasan/init.c > +++ b/mm/kasan/init.c > @@ -279,6 +279,11 @@ int __ref kasan_populate_early_shadow(const void *shadow_start, > return 0; > } > > +void __init __weak kasan_populate_early_vm_area_shadow(void *start, > + unsigned long size) > +{ > +} I'm just wondering if this could be a generic function, perhaps with an appropriate IS_ENABLED() check of a generic Kconfig option (CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK ?) to short-circuit it, if it's not only an arm64 problem. But I haven't looked much further, so would appeal to you to either confirm or reject this idea. Thanks, -- Marco