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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5EB0BC19F2D for ; Tue, 9 Aug 2022 08:15:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 96FA86B0071; Tue, 9 Aug 2022 04:15:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 91FF58E0001; Tue, 9 Aug 2022 04:15:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7E77B6B0073; Tue, 9 Aug 2022 04:15:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 6D2186B0071 for ; Tue, 9 Aug 2022 04:15:55 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 349FF1602C1 for ; Tue, 9 Aug 2022 08:15:55 +0000 (UTC) X-FDA: 79779345870.05.0196F0B Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf27.hostedemail.com (Postfix) with ESMTP id 464D440064 for ; Tue, 9 Aug 2022 08:15:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660032953; 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=i/7QmR2udLKWU2FTMqK09JxCCe/ubs98ULH8N/JxdBc=; b=XifCaS0SbLOYUuOpq+xWwg4lfjiVGIfkc+wg5xEPw8mjbe0Wsfzyo0mVJMBhGJi9JdVr5O sXYeyvzYS7kd8UwE96tgDjLwIslXCTZVuuIQLtdZwh9uUG4h6lQQr8q1/EZe+9B/4sTKXX g3rtZ4lGxdn48cmoXZolhTJkupFxwu4= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-423-OZl5ZcL2OEWI002Do5ncyg-1; Tue, 09 Aug 2022 04:15:52 -0400 X-MC-Unique: OZl5ZcL2OEWI002Do5ncyg-1 Received: by mail-wm1-f70.google.com with SMTP id ay31-20020a05600c1e1f00b003a53bda5b0eso3337648wmb.0 for ; Tue, 09 Aug 2022 01:15:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:organization:from:references :cc:to:content-language:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc; bh=i/7QmR2udLKWU2FTMqK09JxCCe/ubs98ULH8N/JxdBc=; b=sU2n3bAJimmIjB5NN+X4+UuaWTPWIhDCGZWDRnYHqgIaw681NeIwGb+svTJCesHFft 4/Ffy6dQp+c3orfMvgMACB7SDG0mW0JOjB0766vqkk4+PecUtJHESEBND9qlwnXiO2m0 KFY9UZjzN9tKkWN51MLH8KbN1eLljx+4YsQ0Iqa6zUSmSBmWp8VcGXRHV8Vw+k4VIdXX OW8Z/AwOMUFdvRNXhwj8qILt1xwmRhOe0b0EQBOJ5n+XEmf9znjQdgTVIxUsgh36riup OAIo7OVOSTDauI/l9DgEfpMyMEqqo2MiBEQIaOhGkzZL825VFzzamR98i7gPOkwyFzF1 YBCw== X-Gm-Message-State: ACgBeo1PaFnEN+rPZpfART/AWyErVXgJ9BZooh1xwsy1OBjaerG8T/HI 5HZ9+DO6eX5+sFsnTglWpMgKB1GscPMdnjNkqWiKRxnBvsA6Fc8zG1bP5Ypr3asoHTiDAukMepR fkvolsUW/f3w= X-Received: by 2002:a05:6000:711:b0:220:63a5:954c with SMTP id bs17-20020a056000071100b0022063a5954cmr13265928wrb.667.1660032951174; Tue, 09 Aug 2022 01:15:51 -0700 (PDT) X-Google-Smtp-Source: AA6agR4RkwnzP+5IczJUCC+Wv0NDQRP6KkwukKaB7wh492u+icviVRyiUTFwWQT25QDFtg2eUkbyDA== X-Received: by 2002:a05:6000:711:b0:220:63a5:954c with SMTP id bs17-20020a056000071100b0022063a5954cmr13265917wrb.667.1660032950929; Tue, 09 Aug 2022 01:15:50 -0700 (PDT) Received: from ?IPV6:2003:d8:2f15:c300:d2ce:1fb5:2460:179a? (p200300d82f15c300d2ce1fb52460179a.dip0.t-ipconnect.de. [2003:d8:2f15:c300:d2ce:1fb5:2460:179a]) by smtp.gmail.com with ESMTPSA id a5-20020adffb85000000b0021e45afa7b0sm12800466wrr.109.2022.08.09.01.15.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 09 Aug 2022 01:15:50 -0700 (PDT) Message-ID: <6504c796-513a-3785-22a8-a933de37bf96@redhat.com> Date: Tue, 9 Aug 2022 10:15:49 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] mm: re-allow pinning of zero pfns (again) To: Alex Williamson , alex.sierra@amd.com, akpm@linux-foundation.org Cc: hch@lst.de, Felix.Kuehling@amd.com, apopple@nvidia.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <166002010021.381133.11357879752637949308.stgit@omen> From: David Hildenbrand Organization: Red Hat In-Reply-To: <166002010021.381133.11357879752637949308.stgit@omen> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660032954; a=rsa-sha256; cv=none; b=5Nrr6DqVykmhTKSGRNVxQR9n1IO11I7lqb6IcJUS/oMOCaD3XzpBELk3+BI49O7hpkmIXr HS9pYsaU3cuf6KPXnmo4jRnJXJStrMPRMMYD8+88CtSGqvkMogOE+ipvb6zEC8+stludtr YBmhL3Hb2fThOeH/Aej5pr4ceeFP46s= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=XifCaS0S; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf27.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660032954; h=from:from:sender: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:dkim-signature; bh=i/7QmR2udLKWU2FTMqK09JxCCe/ubs98ULH8N/JxdBc=; b=WiItcU8HZLBjtvSLcZXZ4rRrtBKPK+lR7b2fti1lo4+nukzLmwYWJL990RvZbBF2O/qmOM gOoHCMi5HMoorBWyYk1AGWX+KE9dsr2BZvacStVry/Ti4Mo4abcMxILTtMPdjXqs/eaXL6 6rX+oY45dG6HIuxYNIJ1B39LUHh7huU= X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 464D440064 Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=XifCaS0S; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf27.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com X-Rspam-User: X-Stat-Signature: 58pyzgttixpoxbytys9uewezwys3prn8 X-HE-Tag: 1660032954-508917 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 09.08.22 06:42, Alex Williamson wrote: > The below referenced commit makes the same error as 1c563432588d ("mm: fix > is_pinnable_page against a cma page"), re-interpreting the logic to exclude > pinning of the zero page, which breaks device assignment with vfio. > > Link: https://lore.kernel.org/all/165490039431.944052.12458624139225785964.stgit@omen > Fixes: f25cbb7a95a2 ("mm: add zone device coherent type memory support") > Signed-off-by: Alex Williamson > --- > include/linux/mm.h | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 18e01474cf6b..772279ed7010 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -1544,9 +1544,8 @@ static inline bool is_longterm_pinnable_page(struct page *page) > if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) > return false; > #endif > - return !(is_device_coherent_page(page) || > - is_zone_movable_page(page) || > - is_zero_pfn(page_to_pfn(page))); > + return !(is_device_coherent_page(page) || is_zone_movable_page(page)) || > + is_zero_pfn(page_to_pfn(page)); > } > #else > static inline bool is_longterm_pinnable_page(struct page *page) :/ I guess the code was moved just at the time the old code was still in place, and when rebasing, the diff in the code was ignored. Reviewed-by: David Hildenbrand I have patches in the works that will properly break COW here to get anon pages instead of pinning the shared zeropage, which is questionable in COW mappings. -- Thanks, David / dhildenb