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 B29CCC433EF for ; Wed, 18 May 2022 13:09:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 30DED6B0074; Wed, 18 May 2022 09:09:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2BDA98D0002; Wed, 18 May 2022 09:09:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1855E8D0001; Wed, 18 May 2022 09:09:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 065166B0074 for ; Wed, 18 May 2022 09:09:42 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id C3D5556D for ; Wed, 18 May 2022 13:09:41 +0000 (UTC) X-FDA: 79478895762.16.04AEF4B Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf11.hostedemail.com (Postfix) with ESMTP id CA2AB400D5 for ; Wed, 18 May 2022 13:09:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ju+39W+MjqK0PaJ3zrGj+hf6cLDd05VvDhYO8wadxW4=; b=lQyS21gGKOGmli7n7NsiTm9LSV 4/6EjxnCsiP1GkaKgZ6zFQy4qB8VMuS2mMmR0/NsEZjxdUH/F3AOfCEyihO2oCGGl+B1sAXmcTMLL 3bvcfP++pICulIArauX1aVTRcFI4kFB8ZvqlkTF02rlZhzcIu1zEOHgfCHiiL64mPk/uARPfD3FXI FHrfn5uQZ8DgJh76MSlY0EPHejJQZg/5dkbkk4BTqB1Slvbq9Mdu6Okejpe/yfnRvcX+2KvWMs1Hi t25/J1lSDPxKk8Pzs8hOciB8g6psEZlzdMqOzWqsg8Ge9g6QOhGopvf3tPHZGT96DApZN4jyrjGNX PHHBUxCA==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nrJQi-002E94-A3; Wed, 18 May 2022 13:09:32 +0000 Date: Wed, 18 May 2022 06:09:32 -0700 From: Christoph Hellwig To: Vivek Kumar Cc: corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, maz@kernel.org, axboe@kernel.dk, rafael@kernel.org, akpm@linux-foundation.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org, linux-pm@vger.kernel.org, linux-mm@kvack.org, len.brown@intel.com, pavel@ucw.cz, paulmck@kernel.org, bp@suse.de, keescook@chromium.org, songmuchun@bytedance.com, rdunlap@infradead.org, damien.lemoal@opensource.wdc.com, pasha.tatashin@soleen.com, tabba@google.com, ardb@kernel.org, tsoni@quicinc.com, quic_psodagud@quicinc.com, quic_svaddagi@quicinc.com, Prasanna Kumar Subject: Re: [RFC 5/6] Hibernate: Add check for pte_valid in saveable page Message-ID: References: <1652860121-24092-1-git-send-email-quic_vivekuma@quicinc.com> <1652860121-24092-6-git-send-email-quic_vivekuma@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1652860121-24092-6-git-send-email-quic_vivekuma@quicinc.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=lQyS21gG; spf=none (imf11.hostedemail.com: domain of BATV+240e8cd436ded551dd5d+6842+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+240e8cd436ded551dd5d+6842+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: CA2AB400D5 X-Stat-Signature: 4b1pezwdsh1yu1jqhotqxypxfhqsozd4 X-HE-Tag: 1652879374-773110 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 Wed, May 18, 2022 at 01:18:40PM +0530, Vivek Kumar wrote: > Add check for pte_valid in saveable page after being checked for > the rest. This is required as PTE is removed for pages allocated > with dma_alloc_coherent with DMA_ATTR_NO_KERNEL_MAPPING flag set. > This patch makes sure that these pages are not considered for > snapshot. I don't think we ever remove kernel PTEs for DMA_ATTR_NO_KERNEL_MAPPING. If the allocation did come from highmem they never had one to start with. The logic here looks a bit fishy to me.