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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY 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 84301C433E0 for ; Thu, 25 Mar 2021 19:32:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5086961A3A for ; Thu, 25 Mar 2021 19:32:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230064AbhCYTcI (ORCPT ); Thu, 25 Mar 2021 15:32:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229576AbhCYTbr (ORCPT ); Thu, 25 Mar 2021 15:31:47 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D45AC06174A; Thu, 25 Mar 2021 12:31:47 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 0A0F11F46850 From: Gabriel Krisman Bertazi To: Eric Biggers Cc: Shreeya Patel , tytso@mit.edu, adilger.kernel@dilger.ca, jaegeuk@kernel.org, chao@kernel.org, drosen@google.com, yuchao0@huawei.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, kernel@collabora.com, andre.almeida@collabora.com Subject: Re: [PATCH v4 2/5] fs: Check if utf8 encoding is loaded before calling utf8_unload() Organization: Collabora References: <20210325000811.1379641-1-shreeya.patel@collabora.com> <20210325000811.1379641-3-shreeya.patel@collabora.com> Date: Thu, 25 Mar 2021 15:31:42 -0400 In-Reply-To: (Eric Biggers's message of "Thu, 25 Mar 2021 12:21:49 -0700") Message-ID: <878s6bt4gx.fsf@collabora.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Eric Biggers writes: > On Thu, Mar 25, 2021 at 05:38:08AM +0530, Shreeya Patel wrote: >> utf8_unload is being called if CONFIG_UNICODE is enabled. >> The ifdef block doesn't check if utf8 encoding has been loaded >> or not before calling the utf8_unload() function. >> This is not the expected behavior since it would sometimes lead >> to unloading utf8 even before loading it. >> Hence, add a condition which will check if sb->encoding is NOT NULL >> before calling the utf8_unload(). >> >> Reviewed-by: Gabriel Krisman Bertazi >> Signed-off-by: Shreeya Patel >> --- >> fs/ext4/super.c | 6 ++++-- >> fs/f2fs/super.c | 9 ++++++--- >> 2 files changed, 10 insertions(+), 5 deletions(-) >> >> diff --git a/fs/ext4/super.c b/fs/ext4/super.c >> index ad34a37278cd..e438d14f9a87 100644 >> --- a/fs/ext4/super.c >> +++ b/fs/ext4/super.c >> @@ -1259,7 +1259,8 @@ static void ext4_put_super(struct super_block *sb) >> fs_put_dax(sbi->s_daxdev); >> fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy); >> #ifdef CONFIG_UNICODE >> - utf8_unload(sb->s_encoding); >> + if (sb->s_encoding) >> + utf8_unload(sb->s_encoding); >> #endif >> kfree(sbi); >> } > > > What's the benefit of this change? utf8_unload is a no-op when passed a NULL > pointer; why not keep it that way? For the record, it no longer is a no-op after patch 5 of this series. Honestly, I prefer making it explicitly at the caller that we are not entering the function, like the patch does, instead of returning from it immediately. Makes it more readable, IMO. -- Gabriel Krisman Bertazi