From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:34620 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1034555AbdAIP06 (ORCPT ); Mon, 9 Jan 2017 10:26:58 -0500 Subject: Patch "f2fs: hide a maybe-uninitialized warning" has been added to the 4.9-stable tree To: arnd@arndb.de, gregkh@linuxfoundation.org, jaegeuk@kernel.org Cc: , From: Date: Mon, 09 Jan 2017 16:26:32 +0100 Message-ID: <1483975592213106@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled f2fs: hide a maybe-uninitialized warning to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: f2fs-hide-a-maybe-uninitialized-warning.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 230436b3ef3fd7d4a1da19edf5e87bb2d74e0fc2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 2 Nov 2016 14:52:15 +0100 Subject: f2fs: hide a maybe-uninitialized warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Arnd Bergmann commit 230436b3ef3fd7d4a1da19edf5e87bb2d74e0fc2 upstream. gcc is unsure about the use of last_ofs_in_node, which might happen without a prior initialization: fs/f2fs//git/arm-soc/fs/f2fs/data.c: In function ‘f2fs_map_blocks’: fs/f2fs/data.c:799:54: warning: ‘last_ofs_in_node’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) { As pointed out by Chao Yu, the code is actually correct as 'prealloc' is only set if the last_ofs_in_node has been set, the two always get updated together. This initializes last_ofs_in_node to dn.ofs_in_node for each new dnode at the start of the 'next_block' loop, which at that point is a correct initialization as well. I assume that compilers that correctly track the contents of the variables and do not warn about the condition also figure out that they can eliminate the extra assignment here. Fixes: 46008c6d4232 ("f2fs: support in batch multi blocks preallocation") Signed-off-by: Arnd Bergmann Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman --- fs/f2fs/data.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -716,7 +716,7 @@ next_dnode: } prealloc = 0; - ofs_in_node = dn.ofs_in_node; + last_ofs_in_node = ofs_in_node = dn.ofs_in_node; end_offset = ADDRS_PER_PAGE(dn.node_page, inode); next_block: Patches currently in stable-queue which might be from arnd@arndb.de are queue-4.9/asoc-lpass-platform-initialize-dma-channel-number.patch queue-4.9/scsi-mvsas-fix-command_active-typo.patch queue-4.9/debugfs-improve-define_debugfs_attribute-for-config_debug_fs.patch queue-4.9/f2fs-hide-a-maybe-uninitialized-warning.patch