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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88E39C433F5 for ; Sat, 23 Apr 2022 10:25:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234908AbiDWK2L (ORCPT ); Sat, 23 Apr 2022 06:28:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234911AbiDWK1e (ORCPT ); Sat, 23 Apr 2022 06:27:34 -0400 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79AFF10E4 for ; Sat, 23 Apr 2022 03:24:36 -0700 (PDT) Received: by mail-wm1-x32e.google.com with SMTP id f6so76674wma.0 for ; Sat, 23 Apr 2022 03:24:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=JnzJn9/apOse1TRdog9QxKjgDoh08yuT8iYmEPjnkLo=; b=EdRnFs11rrayuYTjd5BRRXOPQ+6lHEDn37pxNXH+HIV3NgWTWMAzKj3mdnLsnM7ntT q05koXcf1+O2OIpp3SfPEK9RptcDXAr6XlEyDnuOQ+Poug3JuqInykzDCJnjQLqq13I2 MXclDmF1rAmIMpbZ9wI77X72rk9zp9AN+zxKfWMhMvHVypCkm9VzQlrIA1S5kh0oBUjg 1DqtbpsbmQfT9LU33EtELKde09//wwPjGq3kWkyKnVk72c1jd12/zfeHXnkK3xMqEKUe dpoCsaBFopex08M2tgjBPQhIiVq2P1Xrzi4licGX4dNkfqg7853kCehT2Af/eJE87sYy S6Nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=JnzJn9/apOse1TRdog9QxKjgDoh08yuT8iYmEPjnkLo=; b=iHfiMqegn+dM2owAmFgEkWFgcD9p+B+2EqDCZLhnnz+2+L05DJt1I7KvWgFFUYN0Y7 2PdVuYXYd4MlSkgCoQiXiEpwwBB9dSXeduQNok7xHKyglRgfwkJQs/6lrYUOpKO178Vl DCPxsWTvZqo3m1y+bBLxcLbsoKIFZbixugsJ7jNy48ZvqE/lS/0743ghIwK3Kqk6LTVS 2ofs+mC2I/uyJ9er6of/NXUmkzB6t3sZaS7gMUumfK/iCySex2fGIGSXsZCCv+8m0OyQ JTuuI4s3n90PkrVGM2ukHX9AGGSS+w/ZLdqo6+5uBZ7J3FcwtcMnJusoHGfqv2/1Afy5 Yikg== X-Gm-Message-State: AOAM532TMcNe8ALnaxzQ4q6pGgyj8wcIechbztf4bW0gsJxMfUth4037 nuGE2PYiflig03C+d59QUMTeulBtRjE= X-Google-Smtp-Source: ABdhPJyS1uQmxp9EjFBBuu7Wu0WbDYSAIAiNH9tMqDan9RYRWsD+dh/C82c+oe7q2B0VbV9fc3mpvg== X-Received: by 2002:a05:600c:3641:b0:38e:4b2f:330 with SMTP id y1-20020a05600c364100b0038e4b2f0330mr17410186wmq.180.1650709475085; Sat, 23 Apr 2022 03:24:35 -0700 (PDT) Received: from localhost.localdomain (host-79-50-86-254.retail.telecomitalia.it. [79.50.86.254]) by smtp.gmail.com with ESMTPSA id t15-20020adfeb8f000000b002060d26c211sm4089057wrn.114.2022.04.23.03.24.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 23 Apr 2022 03:24:33 -0700 (PDT) From: "Fabio M. De Francesco" To: Greg Kroah-Hartman , =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Hridya Valsaraju , Suren Baghdasaryan , Ira Weiny , linux-kernel@vger.kernel.org Cc: "Fabio M. De Francesco" Subject: [PATCH 2/3] binder: Use kmap_local_page() in binder_alloc_copy_user_to_buffer() Date: Sat, 23 Apr 2022 12:24:20 +0200 Message-Id: <20220423102421.16869-3-fmdefrancesco@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220423102421.16869-1-fmdefrancesco@gmail.com> References: <20220423102421.16869-1-fmdefrancesco@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The use of kmap() is being deprecated in favor of kmap_local_page() where it is feasible. With kmap_local_page(), the mapping is per thread, CPU local and not globally visible. binder_alloc_copy_user_to_buffer() is a function where the use of kmap_local_page() in place of kmap() is correctly suited because the mapping is local to the thread. Therefore, use kmap_local_page() / kunmap_local(). Signed-off-by: Fabio M. De Francesco --- drivers/android/binder_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 0b3f2f569053..0875c463c002 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -1217,9 +1217,9 @@ binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, page = binder_alloc_get_page(alloc, buffer, buffer_offset, &pgoff); size = min_t(size_t, bytes, PAGE_SIZE - pgoff); - kptr = kmap(page) + pgoff; + kptr = kmap_local_page(page) + pgoff; ret = copy_from_user(kptr, from, size); - kunmap(page); + kunmap_local(kptr); if (ret) return bytes - size + ret; bytes -= size; -- 2.34.1