From nobody Sat Apr 11 07:56:14 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F359C00140 for ; Mon, 15 Aug 2022 12:39:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241694AbiHOMjv (ORCPT ); Mon, 15 Aug 2022 08:39:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241406AbiHOMjo (ORCPT ); Mon, 15 Aug 2022 08:39:44 -0400 Received: from mail.sberdevices.ru (mail.sberdevices.ru [45.89.227.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BE1E23BC3 for ; Mon, 15 Aug 2022 05:39:43 -0700 (PDT) Received: from s-lin-edge02.sberdevices.ru (localhost [127.0.0.1]) by mail.sberdevices.ru (Postfix) with ESMTP id 1FEA15FD09; Mon, 15 Aug 2022 15:39:41 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sberdevices.ru; s=mail; t=1660567181; bh=h3xSKGi14GTF8G5k/6CCFwywk/Utp7TIH930LpgqkZA=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=rReJv9mzVG4WmTOUOqB8Jl6WVci032YIB1/4Pyw4YQVEn078p+fF78MI0fCp/AAPa OvY6t+h1j0gfXLGFH+L5tD+pWysbgfNDih6NRyRAJhS5qK7UO09Y5gFgpA4TIYyvy4 3inrQ0tOuWF2EE4yUjt72TOBbhtoaBbxaN5yA9Ef1iJcjPAlZ1LqVIOzXJD0jnC3ta aASXd0n11qOgZnYHKvA89J+eMOlcSHeWxt+aALmIhO0EguOfKfyLGFDFiJ5DSK6t59 OfvBC5QTnoqS//ZyDhzrOn4c2yvuCsAX6NQaI2e2Nqg2Pg3ctWA4T07Vezv36av0z8 J6b6SRb4ltdhw== Received: from S-MS-EXCH01.sberdevices.ru (S-MS-EXCH01.sberdevices.ru [172.16.1.4]) by mail.sberdevices.ru (Postfix) with ESMTP; Mon, 15 Aug 2022 15:39:41 +0300 (MSK) From: Alexey Romanov To: , , , CC: , , , Alexey Romanov Subject: [PATCH v2 1/2] zsmalloc: zs_object_copy: add clarifying comment Date: Mon, 15 Aug 2022 15:39:29 +0300 Message-ID: <20220815123930.37736-2-avromanov@sberdevices.ru> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20220815123930.37736-1-avromanov@sberdevices.ru> References: <20220815123930.37736-1-avromanov@sberdevices.ru> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [172.16.1.6] X-ClientProxiedBy: S-MS-EXCH01.sberdevices.ru (172.16.1.4) To S-MS-EXCH01.sberdevices.ru (172.16.1.4) X-KSMG-Rule-ID: 4 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Status: not scanned, disabled by settings X-KSMG-AntiSpam-Interceptor-Info: not scanned X-KSMG-AntiPhishing: not scanned, disabled by settings X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 1.1.2.30, bases: 2022/08/15 08:42:00 #20120161 X-KSMG-AntiVirus-Status: Clean, skipped Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Signed-off-by: Alexey Romanov --- mm/zsmalloc.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 5d5fc04385b8..df381ba891ea 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -1564,6 +1564,12 @@ static void zs_object_copy(struct size_class *class,= unsigned long dst, d_off +=3D size; d_size -=3D size; =20 + /* Calling kunmap_atomic(d_addr) is necessary. kunmap_atomic() + * calls must occurs in reverse order of calls to kmap_atomic. + * So, to call kunmap_atomic(s_addr) we should first call=20 + * kunmap_atomic(d_addr). For more details see: + * Documentation/mm/highmem + */ if (s_off >=3D PAGE_SIZE) { kunmap_atomic(d_addr); kunmap_atomic(s_addr); --=20 2.30.1