From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Yang Subject: Re: [PATCH 3/5] mm/mremap: use pmd_addr_end to calculate next in move_page_tables() Date: Wed, 29 Jan 2020 07:29:07 +0800 Message-ID: <20200128232907.GA11467@richard> References: <20200117232254.2792-1-richardw.yang@linux.intel.com> <20200117232254.2792-4-richardw.yang@linux.intel.com> <7147774a-14e9-4ff3-1548-4565f0d214d5@gmail.com> <20200128004301.GD20624@richard> Reply-To: Wei Yang Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dmitry Osipenko Cc: Wei Yang , Russell King - ARM Linux , akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, aneesh.kumar-tEXmvtCZX7AybS5Ee8rs3A@public.gmane.org, kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org, yang.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org, thellstrom-pghWNbHTmq7QT0dZR+AlfA@public.gmane.org, Thierry Reding , Jon Hunter , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On Tue, Jan 28, 2020 at 06:59:48PM +0300, Dmitry Osipenko wrote: >28.01.2020 03:43, Wei Yang пишет: >> On Sun, Jan 26, 2020 at 05:47:57PM +0300, Dmitry Osipenko wrote: >>> 18.01.2020 02:22, Wei Yang пишет: >>>> Use the general helper instead of do it by hand. >>>> >>>> Signed-off-by: Wei Yang >>>> --- >>>> mm/mremap.c | 7 ++----- >>>> 1 file changed, 2 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/mm/mremap.c b/mm/mremap.c >>>> index c2af8ba4ba43..a258914f3ee1 100644 >>>> --- a/mm/mremap.c >>>> +++ b/mm/mremap.c >>>> @@ -253,11 +253,8 @@ unsigned long move_page_tables(struct vm_area_struct *vma, >>>> >>>> for (; old_addr < old_end; old_addr += extent, new_addr += extent) { >>>> cond_resched(); >>>> - next = (old_addr + PMD_SIZE) & PMD_MASK; >>>> - /* even if next overflowed, extent below will be ok */ >>>> + next = pmd_addr_end(old_addr, old_end); >>>> extent = next - old_addr; >>>> - if (extent > old_end - old_addr) >>>> - extent = old_end - old_addr; >>>> old_pmd = get_old_pmd(vma->vm_mm, old_addr); >>>> if (!old_pmd) >>>> continue; >>>> @@ -301,7 +298,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, >>>> >>>> if (pte_alloc(new_vma->vm_mm, new_pmd)) >>>> break; >>>> - next = (new_addr + PMD_SIZE) & PMD_MASK; >>>> + next = pmd_addr_end(new_addr, new_addr + len); >>>> if (extent > next - new_addr) >>>> extent = next - new_addr; >>>> move_ptes(vma, old_pmd, old_addr, old_addr + extent, new_vma, >>>> >>> >>> Hello Wei, >>> >>> Starting with next-20200122, I'm seeing the following in KMSG on NVIDIA >>> Tegra (ARM32): >>> >>> BUG: Bad rss-counter state mm:(ptrval) type:MM_ANONPAGES val:190 >>> >> >> Thanks. >> >> Would you mind letting me know which case you are testing? > >Nothing special, systemd starts to fall apart during boot. > >> Or the special thing is 32-bit platform? >I have a limited knowledge about mm/, so can't provide detailed explanation. > >Please take a look at this: > >[1] >https://elixir.bootlin.com/linux/v5.5/source/arch/arm/include/asm/pgtable-2level.h#L210 > >[2] >https://elixir.bootlin.com/linux/v5.5/source/include/asm-generic/pgtable.h#L549 > >[3] >https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c0ba10b512eb2e2a3888b6e6cc0e089f5e7a191b Thanks, I see the difference here. If this is the case, we can't use pmd_addr_end() to simplify the calculation. This changes the behavior. I would prepare another patch set to fix this. Would you mind helping me verify on your platform? -- Wei Yang Help you, Help me 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=-10.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_DBL_ABUSE_MALW,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 60B0DC2D0DB for ; Tue, 28 Jan 2020 23:29:11 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 32ED9207FD for ; Tue, 28 Jan 2020 23:29:11 +0000 (UTC) Authentication-Results: mail.kernel.org; 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charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gVHVlLCBKYW4gMjgsIDIwMjAgYXQgMDY6NTk6NDhQTSArMDMwMCwgRG1pdHJ5IE9zaXBlbmtv IHdyb3RlOgo+MjguMDEuMjAyMCAwMzo0MywgV2VpIFlhbmcg0L/QuNGI0LXRgjoKPj4gT24gU3Vu LCBKYW4gMjYsIDIwMjAgYXQgMDU6NDc6NTdQTSArMDMwMCwgRG1pdHJ5IE9zaXBlbmtvIHdyb3Rl Ogo+Pj4gMTguMDEuMjAyMCAwMjoyMiwgV2VpIFlhbmcg0L/QuNGI0LXRgjoKPj4+PiBVc2UgdGhl IGdlbmVyYWwgaGVscGVyIGluc3RlYWQgb2YgZG8gaXQgYnkgaGFuZC4KPj4+Pgo+Pj4+IFNpZ25l ZC1vZmYtYnk6IFdlaSBZYW5nIDxyaWNoYXJkdy55YW5nQGxpbnV4LmludGVsLmNvbT4KPj4+PiAt LS0KPj4+PiAgbW0vbXJlbWFwLmMgfCA3ICsrLS0tLS0KPj4+PiAgMSBmaWxlIGNoYW5nZWQsIDIg aW5zZXJ0aW9ucygrKSwgNSBkZWxldGlvbnMoLSkKPj4+Pgo+Pj4+IGRpZmYgLS1naXQgYS9tbS9t cmVtYXAuYyBiL21tL21yZW1hcC5jCj4+Pj4gaW5kZXggYzJhZjhiYTRiYTQzLi5hMjU4OTE0ZjNl ZTEgMTAwNjQ0Cj4+Pj4gLS0tIGEvbW0vbXJlbWFwLmMKPj4+PiArKysgYi9tbS9tcmVtYXAuYwo+ Pj4+IEBAIC0yNTMsMTEgKzI1Myw4IEBAIHVuc2lnbmVkIGxvbmcgbW92ZV9wYWdlX3RhYmxlcyhz dHJ1Y3Qgdm1fYXJlYV9zdHJ1Y3QgKnZtYSwKPj4+PiAgCj4+Pj4gIAlmb3IgKDsgb2xkX2FkZHIg PCBvbGRfZW5kOyBvbGRfYWRkciArPSBleHRlbnQsIG5ld19hZGRyICs9IGV4dGVudCkgewo+Pj4+ ICAJCWNvbmRfcmVzY2hlZCgpOwo+Pj4+IC0JCW5leHQgPSAob2xkX2FkZHIgKyBQTURfU0laRSkg JiBQTURfTUFTSzsKPj4+PiAtCQkvKiBldmVuIGlmIG5leHQgb3ZlcmZsb3dlZCwgZXh0ZW50IGJl bG93IHdpbGwgYmUgb2sgKi8KPj4+PiArCQluZXh0ID0gcG1kX2FkZHJfZW5kKG9sZF9hZGRyLCBv bGRfZW5kKTsKPj4+PiAgCQlleHRlbnQgPSBuZXh0IC0gb2xkX2FkZHI7Cj4+Pj4gLQkJaWYgKGV4 dGVudCA+IG9sZF9lbmQgLSBvbGRfYWRkcikKPj4+PiAtCQkJZXh0ZW50ID0gb2xkX2VuZCAtIG9s ZF9hZGRyOwo+Pj4+ICAJCW9sZF9wbWQgPSBnZXRfb2xkX3BtZCh2bWEtPnZtX21tLCBvbGRfYWRk cik7Cj4+Pj4gIAkJaWYgKCFvbGRfcG1kKQo+Pj4+ICAJCQljb250aW51ZTsKPj4+PiBAQCAtMzAx LDcgKzI5OCw3IEBAIHVuc2lnbmVkIGxvbmcgbW92ZV9wYWdlX3RhYmxlcyhzdHJ1Y3Qgdm1fYXJl YV9zdHJ1Y3QgKnZtYSwKPj4+PiAgCj4+Pj4gIAkJaWYgKHB0ZV9hbGxvYyhuZXdfdm1hLT52bV9t bSwgbmV3X3BtZCkpCj4+Pj4gIAkJCWJyZWFrOwo+Pj4+IC0JCW5leHQgPSAobmV3X2FkZHIgKyBQ TURfU0laRSkgJiBQTURfTUFTSzsKPj4+PiArCQluZXh0ID0gcG1kX2FkZHJfZW5kKG5ld19hZGRy LCBuZXdfYWRkciArIGxlbik7Cj4+Pj4gIAkJaWYgKGV4dGVudCA+IG5leHQgLSBuZXdfYWRkcikK Pj4+PiAgCQkJZXh0ZW50ID0gbmV4dCAtIG5ld19hZGRyOwo+Pj4+ICAJCW1vdmVfcHRlcyh2bWEs IG9sZF9wbWQsIG9sZF9hZGRyLCBvbGRfYWRkciArIGV4dGVudCwgbmV3X3ZtYSwKPj4+Pgo+Pj4K Pj4+IEhlbGxvIFdlaSwKPj4+Cj4+PiBTdGFydGluZyB3aXRoIG5leHQtMjAyMDAxMjIsIEknbSBz ZWVpbmcgdGhlIGZvbGxvd2luZyBpbiBLTVNHIG9uIE5WSURJQQo+Pj4gVGVncmEgKEFSTTMyKToK Pj4+Cj4+PiAgQlVHOiBCYWQgcnNzLWNvdW50ZXIgc3RhdGUgbW06KHB0cnZhbCkgdHlwZTpNTV9B Tk9OUEFHRVMgdmFsOjE5MAo+Pj4KPj4gCj4+IFRoYW5rcy4KPj4gCj4+IFdvdWxkIHlvdSBtaW5k IGxldHRpbmcgbWUga25vdyB3aGljaCBjYXNlIHlvdSBhcmUgdGVzdGluZz8KPgo+Tm90aGluZyBz cGVjaWFsLCBzeXN0ZW1kIHN0YXJ0cyB0byBmYWxsIGFwYXJ0IGR1cmluZyBib290Lgo+Cj4+IE9y IHRoZSBzcGVjaWFsIHRoaW5nIGlzIDMyLWJpdCBwbGF0Zm9ybT8KPkkgaGF2ZSBhIGxpbWl0ZWQg a25vd2xlZGdlIGFib3V0IG1tLywgc28gY2FuJ3QgcHJvdmlkZSBkZXRhaWxlZCBleHBsYW5hdGlv bi4KPgo+UGxlYXNlIHRha2UgYSBsb29rIGF0IHRoaXM6Cj4KPlsxXQo+aHR0cHM6Ly9lbGl4aXIu Ym9vdGxpbi5jb20vbGludXgvdjUuNS9zb3VyY2UvYXJjaC9hcm0vaW5jbHVkZS9hc20vcGd0YWJs ZS0ybGV2ZWwuaCNMMjEwCj4KPlsyXQo+aHR0cHM6Ly9lbGl4aXIuYm9vdGxpbi5jb20vbGludXgv djUuNS9zb3VyY2UvaW5jbHVkZS9hc20tZ2VuZXJpYy9wZ3RhYmxlLmgjTDU0OQo+Cj5bM10KPmh0 dHBzOi8vZ2l0Lmtlcm5lbC5vcmcvcHViL3NjbS9saW51eC9rZXJuZWwvZ2l0L3RvcnZhbGRzL2xp bnV4LmdpdC9jb21taXQvP2lkPWMwYmExMGI1MTJlYjJlMmEzODg4YjZlNmNjMGUwODlmNWU3YTE5 MWIKClRoYW5rcywgSSBzZWUgdGhlIGRpZmZlcmVuY2UgaGVyZS4KCklmIHRoaXMgaXMgdGhlIGNh c2UsIHdlIGNhbid0IHVzZSBwbWRfYWRkcl9lbmQoKSB0byBzaW1wbGlmeSB0aGUgY2FsY3VsYXRp b24uClRoaXMgY2hhbmdlcyB0aGUgYmVoYXZpb3IuCgpJIHdvdWxkIHByZXBhcmUgYW5vdGhlciBw YXRjaCBzZXQgdG8gZml4IHRoaXMuIFdvdWxkIHlvdSBtaW5kIGhlbHBpbmcgbWUKdmVyaWZ5IG9u IHlvdXIgcGxhdGZvcm0/CgotLSAKV2VpIFlhbmcKSGVscCB5b3UsIEhlbHAgbWUKCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LWFybS1rZXJuZWwg bWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxAbGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8v bGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2xpbnV4LWFybS1rZXJuZWwK 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=-13.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 0D89AC2D0DB for ; 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Tue, 28 Jan 2020 23:28:59 +0000 (UTC) X-FDA: 76428635598.13.nest39_143b75750e807 X-HE-Tag: nest39_143b75750e807 X-Filterd-Recvd-Size: 4691 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Tue, 28 Jan 2020 23:28:58 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Jan 2020 15:28:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,375,1574150400"; d="scan'208";a="261613284" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga002.fm.intel.com with ESMTP; 28 Jan 2020 15:28:54 -0800 Date: Wed, 29 Jan 2020 07:29:07 +0800 From: Wei Yang To: Dmitry Osipenko Cc: Wei Yang , Russell King - ARM Linux , akpm@linux-foundation.org, dan.j.williams@intel.com, aneesh.kumar@linux.ibm.com, kirill@shutemov.name, yang.shi@linux.alibaba.com, thellstrom@vmware.com, Thierry Reding , Jon Hunter , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "linux-tegra@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH 3/5] mm/mremap: use pmd_addr_end to calculate next in move_page_tables() Message-ID: <20200128232907.GA11467@richard> Reply-To: Wei Yang References: <20200117232254.2792-1-richardw.yang@linux.intel.com> <20200117232254.2792-4-richardw.yang@linux.intel.com> <7147774a-14e9-4ff3-1548-4565f0d214d5@gmail.com> <20200128004301.GD20624@richard> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jan 28, 2020 at 06:59:48PM +0300, Dmitry Osipenko wrote: >28.01.2020 03:43, Wei Yang =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >> On Sun, Jan 26, 2020 at 05:47:57PM +0300, Dmitry Osipenko wrote: >>> 18.01.2020 02:22, Wei Yang =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >>>> Use the general helper instead of do it by hand. >>>> >>>> Signed-off-by: Wei Yang >>>> --- >>>> mm/mremap.c | 7 ++----- >>>> 1 file changed, 2 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/mm/mremap.c b/mm/mremap.c >>>> index c2af8ba4ba43..a258914f3ee1 100644 >>>> --- a/mm/mremap.c >>>> +++ b/mm/mremap.c >>>> @@ -253,11 +253,8 @@ unsigned long move_page_tables(struct vm_area_s= truct *vma, >>>> =20 >>>> for (; old_addr < old_end; old_addr +=3D extent, new_addr +=3D ext= ent) { >>>> cond_resched(); >>>> - next =3D (old_addr + PMD_SIZE) & PMD_MASK; >>>> - /* even if next overflowed, extent below will be ok */ >>>> + next =3D pmd_addr_end(old_addr, old_end); >>>> extent =3D next - old_addr; >>>> - if (extent > old_end - old_addr) >>>> - extent =3D old_end - old_addr; >>>> old_pmd =3D get_old_pmd(vma->vm_mm, old_addr); >>>> if (!old_pmd) >>>> continue; >>>> @@ -301,7 +298,7 @@ unsigned long move_page_tables(struct vm_area_st= ruct *vma, >>>> =20 >>>> if (pte_alloc(new_vma->vm_mm, new_pmd)) >>>> break; >>>> - next =3D (new_addr + PMD_SIZE) & PMD_MASK; >>>> + next =3D pmd_addr_end(new_addr, new_addr + len); >>>> if (extent > next - new_addr) >>>> extent =3D next - new_addr; >>>> move_ptes(vma, old_pmd, old_addr, old_addr + extent, new_vma, >>>> >>> >>> Hello Wei, >>> >>> Starting with next-20200122, I'm seeing the following in KMSG on NVID= IA >>> Tegra (ARM32): >>> >>> BUG: Bad rss-counter state mm:(ptrval) type:MM_ANONPAGES val:190 >>> >>=20 >> Thanks. >>=20 >> Would you mind letting me know which case you are testing? > >Nothing special, systemd starts to fall apart during boot. > >> Or the special thing is 32-bit platform? >I have a limited knowledge about mm/, so can't provide detailed explanat= ion. > >Please take a look at this: > >[1] >https://elixir.bootlin.com/linux/v5.5/source/arch/arm/include/asm/pgtabl= e-2level.h#L210 > >[2] >https://elixir.bootlin.com/linux/v5.5/source/include/asm-generic/pgtable= .h#L549 > >[3] >https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi= t/?id=3Dc0ba10b512eb2e2a3888b6e6cc0e089f5e7a191b Thanks, I see the difference here. If this is the case, we can't use pmd_addr_end() to simplify the calculat= ion. This changes the behavior. I would prepare another patch set to fix this. Would you mind helping me verify on your platform? --=20 Wei Yang Help you, Help me