On Wed, Jul 17, 2013 at 12:43:56PM -0700, Darrick J. Wong wrote: > I also wrote a script that fills a fs, maliciously marks all the fs metadata > blocks as free, and writes more files to the fs, with the result that you > corrupt the metadata. I wonder if it's feasible to modify mballoc to check > that it's not handing out well known metadata locations to files? We have that --- it's the block_validity mount option. I use it regularly for testing. It's off by default because it does take a bit more CPU time for every single block allocation and deallocation. It would be useful if someone who had access to fast PCIe-attached flash tried to measure the CPU utilization of a metadata-intensive workload (such as fs_mark) with and without block_validity. If the overhead is negligible, we could enable this by default, and remove the mount option. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
