From: Junfeng Yang Subject: [CHECKER] inconsistent NFS stat cache (NFS on ext3, 2.6.11) Date: Sat, 12 Mar 2005 03:56:14 -0800 (PST) Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Linux Kernel Mailing List , , To: nfs@lists.sourceforge.net Sender: ext2-devel-admin@lists.sourceforge.net Errors-To: ext2-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: List-ID: Hi, We checked NFS on top of ext3 using FiSC (our file system model checker) and found a case where NFS stat cache can contain inconsistent entries. Basically, to trigger this inconsistency, just do the following steps: 1. create a file A1, write a few bytes to it, so A1 is 4 words 2. create a hard link A2, pointing to A1 3. stat on A2. A2's size is 4 words 4. truncate A1 to a larger size, write a few bytes at the end. now it's 1031 words. 5. stat on A2. it's size is still 4 words, which should be 1031 words We have a test case to re-create this warning. You can download it at http://fisc.stanford.edu/bug16/crash.c. It includes some sudo commands to mount nfs partitions, which you might want to change according to your local settings. cat /etc/exports shows: /mnt/sbd0-export localhost(rw,sync) /mnt/sbd1-export localhost(rw,sync) Let me know if you have any problems reproducing the warning. We'd appreciate any confirmations/clarifications. -Junfeng ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click