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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 8586CC07E9A for ; Wed, 14 Jul 2021 08:09:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 178566135A for ; Wed, 14 Jul 2021 08:09:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 178566135A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 528B56B0096; Wed, 14 Jul 2021 04:09:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4B18F6B0098; Wed, 14 Jul 2021 04:09:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 352216B0099; Wed, 14 Jul 2021 04:09:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0140.hostedemail.com [216.40.44.140]) by kanga.kvack.org (Postfix) with ESMTP id 094B76B0096 for ; Wed, 14 Jul 2021 04:09:53 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id ED0F48245571 for ; Wed, 14 Jul 2021 08:09:51 +0000 (UTC) X-FDA: 78360469782.15.3D5A03D Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by imf05.hostedemail.com (Postfix) with ESMTP id 104355009775 for ; Wed, 14 Jul 2021 08:09:46 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10044"; a="210349527" X-IronPort-AV: E=Sophos;i="5.84,238,1620716400"; d="scan'208";a="210349527" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 01:09:37 -0700 X-IronPort-AV: E=Sophos;i="5.84,238,1620716400"; d="scan'208";a="428015671" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 01:09:36 -0700 Date: Wed, 14 Jul 2021 01:09:35 -0700 From: Ira Weiny To: Christoph Hellwig Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/2] mm: call flush_dcache_page in memcpy_to_page and memzero_page Message-ID: <20210714080935.GK3169279@iweiny-DESK2.sc.intel.com> References: <20210713055231.137602-1-hch@lst.de> <20210713055231.137602-2-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210713055231.137602-2-hch@lst.de> User-Agent: Mutt/1.11.1 (2018-12-01) Authentication-Results: imf05.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf05.hostedemail.com: domain of ira.weiny@intel.com has no SPF policy when checking 134.134.136.65) smtp.mailfrom=ira.weiny@intel.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 104355009775 X-Stat-Signature: jc3mwckkknpje776bd74dcg8y4aeht7r X-HE-Tag: 1626250186-964780 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, Jul 13, 2021 at 07:52:30AM +0200, Christoph Hellwig wrote: > memcpy_to_page and memzero_page can write to arbitrary pages, which could > be in the page cache or in high memory, so call flush_kernel_dcache_pages > to flush the dcache. > > Fixes: bb90d4bc7b6a ("mm/highmem: Lift memcpy_[to|from]_page to core") > Fixes: 28961998f858 ("iov_iter: lift memzero_page() to highmem.h") > Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny > --- > include/linux/highmem.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/linux/highmem.h b/include/linux/highmem.h > index 8c6e8e996c87..8e7e50a53a12 100644 > --- a/include/linux/highmem.h > +++ b/include/linux/highmem.h > @@ -318,6 +318,7 @@ static inline void memcpy_to_page(struct page *page, size_t offset, > > VM_BUG_ON(offset + len > PAGE_SIZE); > memcpy(to + offset, from, len); > + flush_dcache_page(page); > kunmap_local(to); > } > > @@ -325,6 +326,7 @@ static inline void memzero_page(struct page *page, size_t offset, size_t len) > { > char *addr = kmap_atomic(page); > memset(addr + offset, 0, len); > + flush_dcache_page(page); > kunmap_atomic(addr); > } > > -- > 2.30.2 >