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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 4518DC433ED for ; Mon, 19 Apr 2021 14:00:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1263F61354 for ; Mon, 19 Apr 2021 14:00:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238897AbhDSOAs (ORCPT ); Mon, 19 Apr 2021 10:00:48 -0400 Received: from foss.arm.com ([217.140.110.172]:43492 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230021AbhDSOAs (ORCPT ); Mon, 19 Apr 2021 10:00:48 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0FCD231B; Mon, 19 Apr 2021 07:00:18 -0700 (PDT) Received: from [192.168.1.179] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3FBAA3F7D7; Mon, 19 Apr 2021 07:00:16 -0700 (PDT) Subject: Re: [PATCH v1 3/5] mm: ptdump: Provide page size to notepage() To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , akpm@linux-foundation.org Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-mm@kvack.org References: <1ef6b954fb7b0f4dfc78820f1e612d2166c13227.1618506910.git.christophe.leroy@csgroup.eu> <41819925-3ee5-4771-e98b-0073e8f095cf@arm.com> <1102cda1-b00f-b6ef-6bf3-22068cc11510@arm.com> <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> From: Steven Price Message-ID: <4a76fbda-aa9d-867b-e2eb-a1951780aeec@arm.com> Date: Mon, 19 Apr 2021 15:00:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On 19/04/2021 14:14, Christophe Leroy wrote: > > > Le 16/04/2021 à 12:51, Steven Price a écrit : >> On 16/04/2021 11:38, Christophe Leroy wrote: >>> >>> >>> Le 16/04/2021 à 11:28, Steven Price a écrit : >>>> On 15/04/2021 18:18, Christophe Leroy wrote: >>>> >>>> To be honest I don't fully understand why powerpc requires the >>>> page_size - it appears to be using it purely to find "holes" in the >>>> calls to note_page(), but I haven't worked out why such holes would >>>> occur. >>> >>> I was indeed introduced for KASAN. We have a first commit >>> https://github.com/torvalds/linux/commit/cabe8138 which uses page >>> size to detect whether it is a KASAN like stuff. >>> >>> Then came https://github.com/torvalds/linux/commit/b00ff6d8c as a >>> fix. I can't remember what the problem was exactly, something around >>> the use of hugepages for kernel memory, came as part of the series >>> https://patchwork.ozlabs.org/project/linuxppc-dev/cover/cover.1589866984.git.christophe.leroy@csgroup.eu/ >> >> >> >> Ah, that's useful context. So it looks like powerpc took a different >> route to reducing the KASAN output to x86. >> >> Given the generic ptdump code has handling for KASAN already it should >> be possible to drop that from the powerpc arch code, which I think >> means we don't actually need to provide page size to notepage(). >> Hopefully that means more code to delete ;) >> > > Looking at how the generic ptdump code handles KASAN, I'm a bit sceptic. > > IIUC, it is checking that kasan_early_shadow_pte is in the same page as > the pgtable referred by the PMD entry. But what happens if that PMD > entry is referring another pgtable which is inside the same page as > kasan_early_shadow_pte ? > > Shouldn't the test be > >     if (pmd_page_vaddr(val) == lm_alias(kasan_early_shadow_pte)) >         return note_kasan_page_table(walk, addr); Now I come to look at this code again, I think you're right. On arm64 this doesn't cause a problem - page tables are page sized and page aligned, so there couldn't be any non-KASAN pgtables sharing the page. Obviously that's not necessarily true of other architectures. Feel free to add a patch to your series ;) Steve 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=-10.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 3BE34C433ED for ; Mon, 19 Apr 2021 14:01:06 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9F67561245 for ; Mon, 19 Apr 2021 14:01:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9F67561245 Authentication-Results: mail.kernel.org; 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Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYURp-00BQUn-QS; Mon, 19 Apr 2021 14:00:25 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0FCD231B; Mon, 19 Apr 2021 07:00:18 -0700 (PDT) Received: from [192.168.1.179] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3FBAA3F7D7; Mon, 19 Apr 2021 07:00:16 -0700 (PDT) Subject: Re: [PATCH v1 3/5] mm: ptdump: Provide page size to notepage() To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , akpm@linux-foundation.org Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-mm@kvack.org References: <1ef6b954fb7b0f4dfc78820f1e612d2166c13227.1618506910.git.christophe.leroy@csgroup.eu> <41819925-3ee5-4771-e98b-0073e8f095cf@arm.com> <1102cda1-b00f-b6ef-6bf3-22068cc11510@arm.com> <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> From: Steven Price Message-ID: <4a76fbda-aa9d-867b-e2eb-a1951780aeec@arm.com> Date: Mon, 19 Apr 2021 15:00:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210419_070021_924898_5693629C X-CRM114-Status: GOOD ( 20.89 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gMTkvMDQvMjAyMSAxNDoxNCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPiAKPiAKPiBMZSAx Ni8wNC8yMDIxIMOgIDEyOjUxLCBTdGV2ZW4gUHJpY2UgYSDDqWNyaXTCoDoKPj4gT24gMTYvMDQv MjAyMSAxMTozOCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPj4+Cj4+Pgo+Pj4gTGUgMTYvMDQv MjAyMSDDoCAxMToyOCwgU3RldmVuIFByaWNlIGEgw6ljcml0wqA6Cj4+Pj4gT24gMTUvMDQvMjAy MSAxODoxOCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPj4+Pgo+Pj4+IFRvIGJlIGhvbmVzdCBJ IGRvbid0IGZ1bGx5IHVuZGVyc3RhbmQgd2h5IHBvd2VycGMgcmVxdWlyZXMgdGhlIAo+Pj4+IHBh Z2Vfc2l6ZSAtIGl0IGFwcGVhcnMgdG8gYmUgdXNpbmcgaXQgcHVyZWx5IHRvIGZpbmQgImhvbGVz IiBpbiB0aGUgCj4+Pj4gY2FsbHMgdG8gbm90ZV9wYWdlKCksIGJ1dCBJIGhhdmVuJ3Qgd29ya2Vk IG91dCB3aHkgc3VjaCBob2xlcyB3b3VsZCAKPj4+PiBvY2N1ci4KPj4+Cj4+PiBJIHdhcyBpbmRl ZWQgaW50cm9kdWNlZCBmb3IgS0FTQU4uIFdlIGhhdmUgYSBmaXJzdCBjb21taXQgCj4+PiBodHRw czovL2dpdGh1Yi5jb20vdG9ydmFsZHMvbGludXgvY29tbWl0L2NhYmU4MTM4IHdoaWNoIHVzZXMg cGFnZSAKPj4+IHNpemUgdG8gZGV0ZWN0IHdoZXRoZXIgaXQgaXMgYSBLQVNBTiBsaWtlIHN0dWZm Lgo+Pj4KPj4+IFRoZW4gY2FtZSBodHRwczovL2dpdGh1Yi5jb20vdG9ydmFsZHMvbGludXgvY29t bWl0L2IwMGZmNmQ4YyBhcyBhIAo+Pj4gZml4LiBJIGNhbid0IHJlbWVtYmVyIHdoYXQgdGhlIHBy b2JsZW0gd2FzIGV4YWN0bHksIHNvbWV0aGluZyBhcm91bmQgCj4+PiB0aGUgdXNlIG9mIGh1Z2Vw YWdlcyBmb3Iga2VybmVsIG1lbW9yeSwgY2FtZSBhcyBwYXJ0IG9mIHRoZSBzZXJpZXMgCj4+PiBo dHRwczovL3BhdGNod29yay5vemxhYnMub3JnL3Byb2plY3QvbGludXhwcGMtZGV2L2NvdmVyL2Nv dmVyLjE1ODk4NjY5ODQuZ2l0LmNocmlzdG9waGUubGVyb3lAY3Nncm91cC5ldS8gCj4+Cj4+Cj4+ Cj4+IEFoLCB0aGF0J3MgdXNlZnVsIGNvbnRleHQuIFNvIGl0IGxvb2tzIGxpa2UgcG93ZXJwYyB0 b29rIGEgZGlmZmVyZW50IAo+PiByb3V0ZSB0byByZWR1Y2luZyB0aGUgS0FTQU4gb3V0cHV0IHRv IHg4Ni4KPj4KPj4gR2l2ZW4gdGhlIGdlbmVyaWMgcHRkdW1wIGNvZGUgaGFzIGhhbmRsaW5nIGZv ciBLQVNBTiBhbHJlYWR5IGl0IHNob3VsZCAKPj4gYmUgcG9zc2libGUgdG8gZHJvcCB0aGF0IGZy b20gdGhlIHBvd2VycGMgYXJjaCBjb2RlLCB3aGljaCBJIHRoaW5rIAo+PiBtZWFucyB3ZSBkb24n dCBhY3R1YWxseSBuZWVkIHRvIHByb3ZpZGUgcGFnZSBzaXplIHRvIG5vdGVwYWdlKCkuIAo+PiBI b3BlZnVsbHkgdGhhdCBtZWFucyBtb3JlIGNvZGUgdG8gZGVsZXRlIDspCj4+Cj4gCj4gTG9va2lu ZyBhdCBob3cgdGhlIGdlbmVyaWMgcHRkdW1wIGNvZGUgaGFuZGxlcyBLQVNBTiwgSSdtIGEgYml0 IHNjZXB0aWMuCj4gCj4gSUlVQywgaXQgaXMgY2hlY2tpbmcgdGhhdCBrYXNhbl9lYXJseV9zaGFk b3dfcHRlIGlzIGluIHRoZSBzYW1lIHBhZ2UgYXMgCj4gdGhlIHBndGFibGUgcmVmZXJyZWQgYnkg dGhlIFBNRCBlbnRyeS4gQnV0IHdoYXQgaGFwcGVucyBpZiB0aGF0IFBNRCAKPiBlbnRyeSBpcyBy ZWZlcnJpbmcgYW5vdGhlciBwZ3RhYmxlIHdoaWNoIGlzIGluc2lkZSB0aGUgc2FtZSBwYWdlIGFz IAo+IGthc2FuX2Vhcmx5X3NoYWRvd19wdGUgPwo+IAo+IFNob3VsZG4ndCB0aGUgdGVzdCBiZQo+ IAo+ICDCoMKgwqDCoGlmIChwbWRfcGFnZV92YWRkcih2YWwpID09IGxtX2FsaWFzKGthc2FuX2Vh cmx5X3NoYWRvd19wdGUpKQo+ICDCoMKgwqDCoMKgwqDCoCByZXR1cm4gbm90ZV9rYXNhbl9wYWdl X3RhYmxlKHdhbGssIGFkZHIpOwoKTm93IEkgY29tZSB0byBsb29rIGF0IHRoaXMgY29kZSBhZ2Fp biwgSSB0aGluayB5b3UncmUgcmlnaHQuIE9uIGFybTY0IAp0aGlzIGRvZXNuJ3QgY2F1c2UgYSBw cm9ibGVtIC0gcGFnZSB0YWJsZXMgYXJlIHBhZ2Ugc2l6ZWQgYW5kIHBhZ2UgCmFsaWduZWQsIHNv IHRoZXJlIGNvdWxkbid0IGJlIGFueSBub24tS0FTQU4gcGd0YWJsZXMgc2hhcmluZyB0aGUgcGFn ZS4gCk9idmlvdXNseSB0aGF0J3Mgbm90IG5lY2Vzc2FyaWx5IHRydWUgb2Ygb3RoZXIgYXJjaGl0 ZWN0dXJlcy4KCkZlZWwgZnJlZSB0byBhZGQgYSBwYXRjaCB0byB5b3VyIHNlcmllcyA7KQoKU3Rl dmUKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4 LXJpc2N2IG1haWxpbmcgbGlzdApsaW51eC1yaXNjdkBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6 Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YK 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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 80F22C433B4 for ; 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Tue, 20 Apr 2021 00:00:21 +1000 (AEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0FCD231B; Mon, 19 Apr 2021 07:00:18 -0700 (PDT) Received: from [192.168.1.179] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3FBAA3F7D7; Mon, 19 Apr 2021 07:00:16 -0700 (PDT) Subject: Re: [PATCH v1 3/5] mm: ptdump: Provide page size to notepage() To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , akpm@linux-foundation.org References: <1ef6b954fb7b0f4dfc78820f1e612d2166c13227.1618506910.git.christophe.leroy@csgroup.eu> <41819925-3ee5-4771-e98b-0073e8f095cf@arm.com> <1102cda1-b00f-b6ef-6bf3-22068cc11510@arm.com> <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> From: Steven Price Message-ID: <4a76fbda-aa9d-867b-e2eb-a1951780aeec@arm.com> Date: Mon, 19 Apr 2021 15:00:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 19/04/2021 14:14, Christophe Leroy wrote: > > > Le 16/04/2021 à 12:51, Steven Price a écrit : >> On 16/04/2021 11:38, Christophe Leroy wrote: >>> >>> >>> Le 16/04/2021 à 11:28, Steven Price a écrit : >>>> On 15/04/2021 18:18, Christophe Leroy wrote: >>>> >>>> To be honest I don't fully understand why powerpc requires the >>>> page_size - it appears to be using it purely to find "holes" in the >>>> calls to note_page(), but I haven't worked out why such holes would >>>> occur. >>> >>> I was indeed introduced for KASAN. We have a first commit >>> https://github.com/torvalds/linux/commit/cabe8138 which uses page >>> size to detect whether it is a KASAN like stuff. >>> >>> Then came https://github.com/torvalds/linux/commit/b00ff6d8c as a >>> fix. I can't remember what the problem was exactly, something around >>> the use of hugepages for kernel memory, came as part of the series >>> https://patchwork.ozlabs.org/project/linuxppc-dev/cover/cover.1589866984.git.christophe.leroy@csgroup.eu/ >> >> >> >> Ah, that's useful context. So it looks like powerpc took a different >> route to reducing the KASAN output to x86. >> >> Given the generic ptdump code has handling for KASAN already it should >> be possible to drop that from the powerpc arch code, which I think >> means we don't actually need to provide page size to notepage(). >> Hopefully that means more code to delete ;) >> > > Looking at how the generic ptdump code handles KASAN, I'm a bit sceptic. > > IIUC, it is checking that kasan_early_shadow_pte is in the same page as > the pgtable referred by the PMD entry. But what happens if that PMD > entry is referring another pgtable which is inside the same page as > kasan_early_shadow_pte ? > > Shouldn't the test be > >     if (pmd_page_vaddr(val) == lm_alias(kasan_early_shadow_pte)) >         return note_kasan_page_table(walk, addr); Now I come to look at this code again, I think you're right. On arm64 this doesn't cause a problem - page tables are page sized and page aligned, so there couldn't be any non-KASAN pgtables sharing the page. Obviously that's not necessarily true of other architectures. Feel free to add a patch to your series ;) Steve 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=-10.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 37974C433ED for ; Mon, 19 Apr 2021 14:02:09 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 85E976100A for ; Mon, 19 Apr 2021 14:02:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 85E976100A Authentication-Results: mail.kernel.org; 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Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYURp-00BQUn-QS; Mon, 19 Apr 2021 14:00:25 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0FCD231B; Mon, 19 Apr 2021 07:00:18 -0700 (PDT) Received: from [192.168.1.179] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3FBAA3F7D7; Mon, 19 Apr 2021 07:00:16 -0700 (PDT) Subject: Re: [PATCH v1 3/5] mm: ptdump: Provide page size to notepage() To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , akpm@linux-foundation.org Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-mm@kvack.org References: <1ef6b954fb7b0f4dfc78820f1e612d2166c13227.1618506910.git.christophe.leroy@csgroup.eu> <41819925-3ee5-4771-e98b-0073e8f095cf@arm.com> <1102cda1-b00f-b6ef-6bf3-22068cc11510@arm.com> <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> From: Steven Price Message-ID: <4a76fbda-aa9d-867b-e2eb-a1951780aeec@arm.com> Date: Mon, 19 Apr 2021 15:00:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <627ee414-2f78-94e3-b77b-1013f52e77e3@csgroup.eu> Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210419_070021_924898_5693629C X-CRM114-Status: GOOD ( 20.89 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gMTkvMDQvMjAyMSAxNDoxNCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPiAKPiAKPiBMZSAx Ni8wNC8yMDIxIMOgIDEyOjUxLCBTdGV2ZW4gUHJpY2UgYSDDqWNyaXTCoDoKPj4gT24gMTYvMDQv MjAyMSAxMTozOCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPj4+Cj4+Pgo+Pj4gTGUgMTYvMDQv MjAyMSDDoCAxMToyOCwgU3RldmVuIFByaWNlIGEgw6ljcml0wqA6Cj4+Pj4gT24gMTUvMDQvMjAy MSAxODoxOCwgQ2hyaXN0b3BoZSBMZXJveSB3cm90ZToKPj4+Pgo+Pj4+IFRvIGJlIGhvbmVzdCBJ IGRvbid0IGZ1bGx5IHVuZGVyc3RhbmQgd2h5IHBvd2VycGMgcmVxdWlyZXMgdGhlIAo+Pj4+IHBh Z2Vfc2l6ZSAtIGl0IGFwcGVhcnMgdG8gYmUgdXNpbmcgaXQgcHVyZWx5IHRvIGZpbmQgImhvbGVz IiBpbiB0aGUgCj4+Pj4gY2FsbHMgdG8gbm90ZV9wYWdlKCksIGJ1dCBJIGhhdmVuJ3Qgd29ya2Vk IG91dCB3aHkgc3VjaCBob2xlcyB3b3VsZCAKPj4+PiBvY2N1ci4KPj4+Cj4+PiBJIHdhcyBpbmRl ZWQgaW50cm9kdWNlZCBmb3IgS0FTQU4uIFdlIGhhdmUgYSBmaXJzdCBjb21taXQgCj4+PiBodHRw czovL2dpdGh1Yi5jb20vdG9ydmFsZHMvbGludXgvY29tbWl0L2NhYmU4MTM4IHdoaWNoIHVzZXMg cGFnZSAKPj4+IHNpemUgdG8gZGV0ZWN0IHdoZXRoZXIgaXQgaXMgYSBLQVNBTiBsaWtlIHN0dWZm Lgo+Pj4KPj4+IFRoZW4gY2FtZSBodHRwczovL2dpdGh1Yi5jb20vdG9ydmFsZHMvbGludXgvY29t bWl0L2IwMGZmNmQ4YyBhcyBhIAo+Pj4gZml4LiBJIGNhbid0IHJlbWVtYmVyIHdoYXQgdGhlIHBy b2JsZW0gd2FzIGV4YWN0bHksIHNvbWV0aGluZyBhcm91bmQgCj4+PiB0aGUgdXNlIG9mIGh1Z2Vw YWdlcyBmb3Iga2VybmVsIG1lbW9yeSwgY2FtZSBhcyBwYXJ0IG9mIHRoZSBzZXJpZXMgCj4+PiBo dHRwczovL3BhdGNod29yay5vemxhYnMub3JnL3Byb2plY3QvbGludXhwcGMtZGV2L2NvdmVyL2Nv dmVyLjE1ODk4NjY5ODQuZ2l0LmNocmlzdG9waGUubGVyb3lAY3Nncm91cC5ldS8gCj4+Cj4+Cj4+ Cj4+IEFoLCB0aGF0J3MgdXNlZnVsIGNvbnRleHQuIFNvIGl0IGxvb2tzIGxpa2UgcG93ZXJwYyB0 b29rIGEgZGlmZmVyZW50IAo+PiByb3V0ZSB0byByZWR1Y2luZyB0aGUgS0FTQU4gb3V0cHV0IHRv IHg4Ni4KPj4KPj4gR2l2ZW4gdGhlIGdlbmVyaWMgcHRkdW1wIGNvZGUgaGFzIGhhbmRsaW5nIGZv ciBLQVNBTiBhbHJlYWR5IGl0IHNob3VsZCAKPj4gYmUgcG9zc2libGUgdG8gZHJvcCB0aGF0IGZy b20gdGhlIHBvd2VycGMgYXJjaCBjb2RlLCB3aGljaCBJIHRoaW5rIAo+PiBtZWFucyB3ZSBkb24n dCBhY3R1YWxseSBuZWVkIHRvIHByb3ZpZGUgcGFnZSBzaXplIHRvIG5vdGVwYWdlKCkuIAo+PiBI b3BlZnVsbHkgdGhhdCBtZWFucyBtb3JlIGNvZGUgdG8gZGVsZXRlIDspCj4+Cj4gCj4gTG9va2lu ZyBhdCBob3cgdGhlIGdlbmVyaWMgcHRkdW1wIGNvZGUgaGFuZGxlcyBLQVNBTiwgSSdtIGEgYml0 IHNjZXB0aWMuCj4gCj4gSUlVQywgaXQgaXMgY2hlY2tpbmcgdGhhdCBrYXNhbl9lYXJseV9zaGFk b3dfcHRlIGlzIGluIHRoZSBzYW1lIHBhZ2UgYXMgCj4gdGhlIHBndGFibGUgcmVmZXJyZWQgYnkg dGhlIFBNRCBlbnRyeS4gQnV0IHdoYXQgaGFwcGVucyBpZiB0aGF0IFBNRCAKPiBlbnRyeSBpcyBy ZWZlcnJpbmcgYW5vdGhlciBwZ3RhYmxlIHdoaWNoIGlzIGluc2lkZSB0aGUgc2FtZSBwYWdlIGFz IAo+IGthc2FuX2Vhcmx5X3NoYWRvd19wdGUgPwo+IAo+IFNob3VsZG4ndCB0aGUgdGVzdCBiZQo+ IAo+ICDCoMKgwqDCoGlmIChwbWRfcGFnZV92YWRkcih2YWwpID09IGxtX2FsaWFzKGthc2FuX2Vh cmx5X3NoYWRvd19wdGUpKQo+ICDCoMKgwqDCoMKgwqDCoCByZXR1cm4gbm90ZV9rYXNhbl9wYWdl X3RhYmxlKHdhbGssIGFkZHIpOwoKTm93IEkgY29tZSB0byBsb29rIGF0IHRoaXMgY29kZSBhZ2Fp biwgSSB0aGluayB5b3UncmUgcmlnaHQuIE9uIGFybTY0IAp0aGlzIGRvZXNuJ3QgY2F1c2UgYSBw cm9ibGVtIC0gcGFnZSB0YWJsZXMgYXJlIHBhZ2Ugc2l6ZWQgYW5kIHBhZ2UgCmFsaWduZWQsIHNv IHRoZXJlIGNvdWxkbid0IGJlIGFueSBub24tS0FTQU4gcGd0YWJsZXMgc2hhcmluZyB0aGUgcGFn ZS4gCk9idmlvdXNseSB0aGF0J3Mgbm90IG5lY2Vzc2FyaWx5IHRydWUgb2Ygb3RoZXIgYXJjaGl0 ZWN0dXJlcy4KCkZlZWwgZnJlZSB0byBhZGQgYSBwYXRjaCB0byB5b3VyIHNlcmllcyA7KQoKU3Rl dmUKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4 LWFybS1rZXJuZWwgbWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxAbGlzdHMuaW5mcmFkZWFk Lm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2xpbnV4LWFy bS1rZXJuZWwK