From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joseph Qi Date: Sun, 2 Jun 2013 09:32:04 +0800 Subject: [Ocfs2-devel] [PATCH v2] ocfs2: should not use le32_add_cpu to set ocfs2_dinode i_flags In-Reply-To: <51AA065A.4040400@oracle.com> References: <51A6DA6A.5060301@huawei.com> <20130531152535.a832b5dd6435595798ffb73d@linux-foundation.org> <51AA065A.4040400@oracle.com> Message-ID: <51AAA094.9050508@huawei.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Hi Jeff & Andrew, We found this bug when we do analysis for a read-only filesystem bug that is directly caused by dinode flags mismatch. Of course Jeff you could fix the comments and make it comprehensible. On 2013/6/1 22:34, Jeff Liu wrote: > Hi Andrew, > > Sorry for the late response because I just returned from the LinuxCon/Japan. > > I'm afraid that Joesph can not follow this thread up in time since today is the > weekend in China. So please let me answer your question on behalf of Joesph > as a quick response. > > On 06/01/2013 06:25 AM, Andrew Morton wrote: > >> On Thu, 30 May 2013 12:49:46 +0800 Joseph Qi wrote: >> >>> If we use le32_add_cpu to set ocfs2_dinode i_flags, it may lead to the >>> corresponding flag corrupted. So we should change it to bitwise and/or >>> operation. >>> >> >> The usual question: what is the end-user impact of the bug which was >> just fixed? > > This patch can be treated as a trivial fix. Yes, i_flags is operated in > bitwise context, but those assignments are only happened at the time of > initializing the corresponding OCFS2 private on-disk inode info. Hence > there is no impact from the end-user's perspective. > > However, it's better to replace those three assignments with bitwise operations > since they essentially should be. In this way, we can immediately know that the > business performed on i_flags are in bitwise rather than increasing or decreasing > a count value. > >> For the usual reason: so I and others can decide which kernel versions >> need the fix. > > The current fix comments looks too horrible than it would be. > Can it make your life easier if I repost this patch with the revised > descriptions if Joseph agrees to me? > > > Thanks, > -Jeff > > . >