Hi Johannes and Catalin, Actually bisecting is the best way, but I failed to run fsstress with early 3.15-rcX due to BUG_ONs in mm; recently it seems that most of there-in issues have been resolved. So I pulled the linus tree having: commit 38583f095c5a8138ae2a1c9173d0fd8a9f10e8aa Merge: 8169d30 3ca9e5d Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Date: Tue May 6 13:07:41 2014 -0700 Merge branch 'akpm' (incoming from Andrew) Merge misc fixes from Andrew Morton: "13 fixes" And then when I tested again with Catalin's patch, it still throws the following warning. Is it false alarm? unreferenced object 0xffff880004226da0 (size 576): comm "fsstress", pid 14590, jiffies 4295191259 (age 706.308s) hex dump (first 32 bytes): 01 00 00 00 81 ff ff ff 00 00 00 00 00 00 00 00 ................ 50 89 34 81 ff ff ff ff b8 6d 22 04 00 88 ff ff P.4......m"..... backtrace: [<ffffffff816c02e8>] kmemleak_update_trace+0x58/0x80 [<ffffffff81349517>] radix_tree_node_alloc+0x77/0xa0 [<ffffffff81349718>] __radix_tree_create+0x1d8/0x230 [<ffffffff8113286c>] __add_to_page_cache_locked+0x9c/0x1b0 [<ffffffff811329a8>] add_to_page_cache_lru+0x28/0x80 [<ffffffff81132f58>] grab_cache_page_write_begin+0x98/0xf0 [<ffffffffa02e4bf4>] f2fs_write_begin+0xb4/0x3c0 [f2fs] [<ffffffff81131b77>] generic_perform_write+0xc7/0x1c0 [<ffffffff81133b7d>] __generic_file_aio_write+0x1cd/0x3f0 [<ffffffff81133dfe>] generic_file_aio_write+0x5e/0xe0 [<ffffffff81195c5a>] do_sync_write+0x5a/0x90 [<ffffffff811968d2>] vfs_write+0xc2/0x1d0 [<ffffffff81196daf>] SyS_write+0x4f/0xb0 [<ffffffff816dead2>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff 2014-05-01 (목), 14:41 -0400, Johannes Weiner: > 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)? Yap. > > > > 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? -- Jaegeuk Kim Samsung -- 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