On Wed, 2011-03-30 at 14:27 +0100, Eric Dumazet wrote: > Le mercredi 30 mars 2011 Ã 14:17 +0100, Maxin John a Ãcrit : > > I have compiled the kernel with below given modification in .config > > > > CONFIG_CMDLINE="uhash_entries=256" > > > > After booting with the new kernel, the "kmemleak" no longer complains > > about the "udp_table_init". > > However it do report another possible leak :) > > > > debian-mips:~# cat /sys/kernel/debug/kmemleak > > unreferenced object 0x8f085000 (size 4096): > > comm "swapper", pid 1, jiffies 4294937670 (age 1043.280s) > > hex dump (first 32 bytes): > > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > > backtrace: > > [<801ac7a8>] __kmalloc+0x130/0x180 > > [<80532500>] flow_cache_cpu_prepare+0x50/0xa8 > > [<8052378c>] flow_cache_init_global+0x90/0x138 > > [<80100584>] do_one_initcall+0x174/0x1e0 > > [<8050c348>] kernel_init+0xe4/0x174 > > [<80103d4c>] kernel_thread_helper+0x10/0x18 > > debian-mips:~# > > Hmm, then MIPS kmemleak port might have a problem with percpu data ? > > fcp->hash_table = kzalloc_node(sz, GFP_KERNEL, cpu_to_node(cpu)); > > fcp is a per cpu "struct flow_cache_percpu" I can't figure out what it is. Kmemleak uses this block for scanning the percpu data: for_each_possible_cpu(i) scan_block(__per_cpu_start + per_cpu_offset(i), __per_cpu_end + per_cpu_offset(i), NULL, 1); The __per_cpu_* symbols seem to be correctly defined in the MIPS vmlinux.lds.S as it uses the PERCPU macro directly. Other chunks allocated via pcpu_mem_alloc() should be tracked by kmemleak and either reported as leaks or scanned (and not reporting subsequent blocks referred from the percpu memory). -- Catalin
