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=-7.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 2D444C47089 for ; Thu, 27 May 2021 17:12:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B29F613BF for ; Thu, 27 May 2021 17:12:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236542AbhE0RNv (ORCPT ); Thu, 27 May 2021 13:13:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:27793 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235973AbhE0RNs (ORCPT ); Thu, 27 May 2021 13:13:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622135534; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8Tj882GRDYNKA/Odur5I8qEQKwf2uVi6wQUPaTSmUGk=; b=Fdb1Ofr+zjD6hKwp0RAIB0SY0s2zTC3fQenLSmDuZr1qhM+aRpi+LamHHn3taT214BYep0 DehQSuffonE8xRTW7SIUOuffDOr7+g9MdPthAycXj2c3TNr5W5zDs1tUEdGwwqh9uLcsN0 rYS5KvRcFqE1GYNK+TjwcR8fr7W33rg= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-554-JNuOuIqPNZOhlb26bN4ugA-1; Thu, 27 May 2021 13:12:13 -0400 X-MC-Unique: JNuOuIqPNZOhlb26bN4ugA-1 Received: by mail-wm1-f69.google.com with SMTP id g206-20020a1c39d70000b029016ac627fbe9so438849wma.9 for ; Thu, 27 May 2021 10:12:13 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=8Tj882GRDYNKA/Odur5I8qEQKwf2uVi6wQUPaTSmUGk=; b=gQnB3BUgOyQqkFTlxCUEVvGLdMftinYKi0dIzj6JMxjCr73Ltlr3gkgobdD5pPJreX Wqj0OKLOkNKNiUMsX1VMuCmcTMwM1W1r6XAyDJvXl4yIWzpFd303QR3OFFYkUCScYfUp pV/OE5n2qKscSoBLBv3W1gpcZkuA53tSIGx2xFSRiSPyNUrOCXDI000JL8DiJKYsDmMy uVsspAbyQVyOWek1t5vsaOho02o5wWv9qLNdMScq56tOhkoqU2yGKLYyVCYFPLOkdV0R cdcv723mBP/W8z/+/lcsnicpu4iJiaws2sOOGRwLevHSYT2Gb34unbYyH4UgAantCKnD Z/7g== X-Gm-Message-State: AOAM532lrRuyE5u+ZSY/P9bA79tIgV66L0EnNIuWGQWOPkPnHGOET65u dqW4djT0G7rTZ1jWVXXrTJ1955Gt0Zs3v1YUC169t05TEq/9YKfY946LuOSsd2NZ2fgeKgxtDbh ai6ziosJAU8ofESRa9fD7TGD7 X-Received: by 2002:a1c:3d05:: with SMTP id k5mr4669356wma.9.1622135532221; Thu, 27 May 2021 10:12:12 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzfH6a8f34/9c06VAR9VtQNYysw/6uRvDZUrv050Ei6nDvYjtR9kqnXZGaQdB/PD53PwEWPHA== X-Received: by 2002:a1c:3d05:: with SMTP id k5mr4669322wma.9.1622135531909; Thu, 27 May 2021 10:12:11 -0700 (PDT) Received: from [192.168.3.132] (p4ff230a8.dip0.t-ipconnect.de. [79.242.48.168]) by smtp.gmail.com with ESMTPSA id l8sm4338822wry.55.2021.05.27.10.12.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 27 May 2021 10:12:11 -0700 (PDT) Subject: Re: Arm64 crash while reading memory sysfs To: Mike Rapoport , Qian Cai Cc: Andrew Morton , Catalin Marinas , Anshuman Khandual , Ard Biesheuvel , Linux Memory Management List , Will Deacon , Marc Zyngier , Linux Kernel Mailing List , Linux ARM References: From: David Hildenbrand Organization: Red Hat Message-ID: <3a5fa459-cd00-8a65-3ee1-debc51424a7c@redhat.com> Date: Thu, 27 May 2021 19:12:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >> [ 259.216661][ T1417] test_pages_in_a_zone: pfn 8000 is not valid >> [ 259.226547][ T1417] page:00000000f4aa8c5c is uninitialized and poisoned >> [ 259.226560][ T1417] page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) > > Can you please try Anshuman's patch "arm64/mm: Drop HAVE_ARCH_PFN_VALID": > > https://lore.kernel.org/lkml/1621947349-25421-1-git-send-email-anshuman.khandual@arm.com > > It seems to me that the check for memblock_is_memory() in > arm64::pfn_valid() is what makes init_unavailable_range() to bail out for > section parts that are not actually populated and then we have > VM_BUG_ON_PAGE(PagePoisoned(p)) for these pages. > Oh, that makes sense to me. -- Thanks, David / dhildenb