On Thu, May 01, 2014 at 06:06:10PM +0100, Catalin Marinas wrote: > On Fri, Apr 25, 2014 at 10:45:40AM +0900, Jaegeuk Kim wrote: > > 2. Bug > > This is one of the results, but all the results indicate > > __radix_tree_preload. > > > > unreferenced object 0xffff88002ae2a238 (size 576): > > comm "fsstress", pid 25019, jiffies 4295651360 (age 2276.104s) > > hex dump (first 32 bytes): > > 01 00 00 00 81 ff ff ff 00 00 00 00 00 00 00 00 ................ > > 40 7d 37 81 ff ff ff ff 50 a2 e2 2a 00 88 ff ff @}7.....P..*.... > > backtrace: > > [<ffffffff8170e546>] kmemleak_alloc+0x26/0x50 > > [<ffffffff8119feac>] kmem_cache_alloc+0xdc/0x190 > > [<ffffffff81378709>] __radix_tree_preload+0x49/0xc0 > > [<ffffffff813787a1>] radix_tree_maybe_preload+0x21/0x30 > > [<ffffffff8114bbbc>] add_to_page_cache_lru+0x3c/0xc0 > > [<ffffffff8114c778>] grab_cache_page_write_begin+0x98/0xf0 > > [<ffffffffa02d3151>] f2fs_write_begin+0xa1/0x370 [f2fs] > > [<ffffffff8114af47>] generic_perform_write+0xc7/0x1e0 > > [<ffffffff8114d230>] __generic_file_aio_write+0x1d0/0x400 > > [<ffffffff8114d4c0>] generic_file_aio_write+0x60/0xe0 > > [<ffffffff811b281a>] do_sync_write+0x5a/0x90 > > [<ffffffff811b3575>] vfs_write+0xc5/0x1f0 > > [<ffffffff811b3a92>] SyS_write+0x52/0xb0 > > [<ffffffff81730912>] system_call_fastpath+0x16/0x1b > > [<ffffffffffffffff>] 0xffffffffffffffff > > Do all the backtraces look like the above (coming from > add_to_page_cache_lru)? > > There were some changes in lib/radix-tree.c since 3.14, maybe you could > try reverting them and see if the leaks still appear (cc'ing Johannes). > It could also be a false positive. > > An issue with debugging such cases is that the preloading is common for > multiple radix trees, so the actual radix_tree_node_alloc() could be on > a different path. You could give the patch below a try to see what > backtrace you get (it updates backtrace in radix_tree_node_alloc()). That patch makes a lot of sense to me. I applied it locally but I am unable to reproduce this with page cache heavy workloads. Jaegeuk? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>