On Mon, Jul 11, 2016 at 02:27:39PM -0400, Chris Mason wrote: > > > On 07/11/2016 01:39 PM, Liu Bo wrote: > > eb->io_pages is set in read_extent_buffer_pages(). > > > > In case of readpage failure, for pages that have been added to bio, > > it calls bio_endio and later readpage_io_failed_hook() does the work. > > > > When this eb's page (couldn't be the 1st page) fails to add itself to bio > > due to failure in merge_bio(), it cannot decrease eb->io_pages via bio_endio, > > and ends up with a memory leak eventually. > > > > This lets __do_readpage propagate errors to callers and adds the > > 'atomic_dec(&eb->io_pages)'. > > Thanks for looking at this Liu, how is it currently being tested? I have a btrfs disk image which was corrupted by btrfs-corrupt-block tool, in that image, the chunk tree's content has been removed while the chunk node can be read from read successfully, so we'd get -EIO when trying to read tree root's node since __btrfs_map_block() would fail to find the right item in chunk mapping_tree. Thus, we can test our error handling path in read_extent_buffer_pages(). Thanks, -liubo > > -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
