Hi All, I got the following output when running some tests (I'm not really sure what exactly happened when this bug was triggered): [13850.947279] ============================================================================= [13850.948024] BUG kmalloc-8: Redzone overwritten [13850.948024] ----------------------------------------------------------------------------- [13850.948024] [13850.948024] INFO: 0xffff8800104f6d28-0xffff8800104f6d2b. First byte 0x0 instead of 0xcc [13850.948024] INFO: Allocated in __seq_open_private+0x20/0x5e age=4436 cpu=0 pid=17295 [13850.948024] __slab_alloc.clone.46+0x3e7/0x456 [13850.948024] __kmalloc+0x8c/0x110 [13850.948024] __seq_open_private+0x20/0x5e [13850.948024] seq_open_net+0x3b/0x5d [13850.948024] dev_mc_seq_open+0x15/0x17 [13850.948024] proc_reg_open+0xad/0x127 [13850.948024] __dentry_open+0x1a0/0x2fe [13850.948024] nameidata_to_filp+0x63/0x6a [13850.948024] do_last+0x59e/0x5cb [13850.948024] path_openat+0xcd/0x35d [13850.948024] do_filp_open+0x38/0x84 [13850.948024] do_sys_open+0x6f/0x101 [13850.948024] sys_open+0x1b/0x1d [13850.948024] system_call_fastpath+0x16/0x1b [13850.948024] INFO: Freed in seq_release_private+0x26/0x45 age=30272 cpu=0 pid=17283 [13850.948024] __slab_free+0x35/0x1dc [13850.948024] kfree+0xb6/0xbf [13850.948024] seq_release_private+0x26/0x45 [13850.948024] seq_release_net+0x32/0x3b [13850.948024] proc_reg_release+0xd9/0xf6 [13850.948024] fput+0x11e/0x1dc [13850.948024] filp_close+0x6e/0x79 [13850.948024] put_files_struct+0xcc/0x196 [13850.948024] exit_files+0x46/0x4f [13850.948024] do_exit+0x264/0x75c [13850.948024] do_group_exit+0x83/0xb1 [13850.948024] sys_exit_group+0x12/0x16 [13850.948024] system_call_fastpath+0x16/0x1b [13850.948024] INFO: Slab 0xffffea0000413d80 objects=12 used=8 fp=0xffff8800104f6000 flags=0x10000000000081 [13850.948024] INFO: Object 0xffff8800104f6d20 @offset=3360 fp=0xffff8800104f6e70 [13850.948024] [13850.948024] Bytes b4 ffff8800104f6d10: 39 64 00 00 01 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a 9d......ZZZZZZZZ [13850.948024] Object ffff8800104f6d20: 00 a9 38 83 ff ff ff ff ..8..... [13850.948024] Redzone ffff8800104f6d28: 00 00 00 00 cc cc cc cc ........ [13850.948024] Padding ffff8800104f6e68: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ [13850.948024] Pid: 17295, comm: trinity Tainted: G W 3.2.0-rc2-sasha-00146-gc729049-dirty #15 [13850.948024] Call Trace: [13850.948024] [<ffffffff8112c8f6>] ? print_section+0x38/0x3a [13850.948024] [<ffffffff8112ca21>] print_trailer+0x129/0x132 [13850.948024] [<ffffffff8112cd02>] check_bytes_and_report+0xb2/0xeb [13850.948024] [<ffffffff8115bacc>] ? __seq_open_private+0x31/0x5e [13850.948024] [<ffffffff8112d811>] check_object+0x4e/0x1ae [13850.948024] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [13850.948024] [<ffffffff8112e723>] free_debug_processing+0x96/0x1dc [13850.948024] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [13850.948024] [<ffffffff8112ec07>] __slab_free+0x35/0x1dc [13850.948024] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [13850.948024] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [13850.948024] [<ffffffff81626be3>] ? debug_check_no_obj_freed+0x12/0x17 [13850.948024] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [13850.948024] [<ffffffff8113041f>] kfree+0xb6/0xbf [13850.948024] [<ffffffff81196f4b>] ? single_open_net+0x54/0x54 [13850.948024] [<ffffffff8115ba7c>] seq_release_private+0x26/0x45 [13850.948024] [<ffffffff81196f7d>] seq_release_net+0x32/0x3b [13850.948024] [<ffffffff8118dc6c>] proc_reg_release+0xd9/0xf6 [13850.948024] [<ffffffff811418cf>] fput+0x11e/0x1dc [13850.948024] [<ffffffff8113f3d8>] filp_close+0x6e/0x79 [13850.948024] [<ffffffff81089f17>] put_files_struct+0xcc/0x196 [13850.948024] [<ffffffff8108a074>] exit_files+0x46/0x4f [13850.948024] [<ffffffff8108a756>] do_exit+0x264/0x75c [13850.948024] [<ffffffff8113f67c>] ? fsnotify_modify+0x60/0x68 [13850.948024] [<ffffffff81b96f8a>] ? sysret_check+0x2e/0x69 [13850.948024] [<ffffffff8108ad01>] do_group_exit+0x83/0xb1 [13850.948024] [<ffffffff8108ad41>] sys_exit_group+0x12/0x16 [13850.948024] [<ffffffff81b96f52>] system_call_fastpath+0x16/0x1b [13850.948024] FIX kmalloc-8: Restoring 0xffff8800104f6d28-0xffff8800104f6d2b=0xcc [13850.948024] [14925.113722] ============================================================================= [14925.114041] BUG kmalloc-8: Redzone overwritten [14925.114041] ----------------------------------------------------------------------------- [14925.114041] [14925.114041] INFO: 0xffff8800104f2d28-0xffff8800104f2d2b. First byte 0x0 instead of 0xcc [14925.114041] INFO: Allocated in __seq_open_private+0x20/0x5e age=6777 cpu=0 pid=17491 [14925.114041] __slab_alloc.clone.46+0x3e7/0x456 [14925.114041] __kmalloc+0x8c/0x110 [14925.114041] __seq_open_private+0x20/0x5e [14925.114041] seq_open_net+0x3b/0x5d [14925.114041] dev_mc_seq_open+0x15/0x17 [14925.114041] proc_reg_open+0xad/0x127 [14925.114041] __dentry_open+0x1a0/0x2fe [14925.114041] nameidata_to_filp+0x63/0x6a [14925.114041] do_last+0x59e/0x5cb [14925.114041] path_openat+0xcd/0x35d [14925.114041] do_filp_open+0x38/0x84 [14925.114041] do_sys_open+0x6f/0x101 [14925.114041] sys_open+0x1b/0x1d [14925.114041] system_call_fastpath+0x16/0x1b [14925.114041] INFO: Freed in seq_release_private+0x26/0x45 age=30836 cpu=0 pid=17487 [14925.114041] __slab_free+0x35/0x1dc [14925.114041] kfree+0xb6/0xbf [14925.114041] seq_release_private+0x26/0x45 [14925.114041] seq_release_net+0x32/0x3b [14925.114041] proc_reg_release+0xd9/0xf6 [14925.114041] fput+0x11e/0x1dc [14925.114041] filp_close+0x6e/0x79 [14925.114041] put_files_struct+0xcc/0x196 [14925.114041] exit_files+0x46/0x4f [14925.114041] do_exit+0x264/0x75c [14925.114041] do_group_exit+0x83/0xb1 [14925.114041] sys_exit_group+0x12/0x16 [14925.114041] system_call_fastpath+0x16/0x1b [14925.114041] INFO: Slab 0xffffea0000413c80 objects=12 used=11 fp=0xffff8800104f27e0 flags=0x10000000000081 [14925.114041] INFO: Object 0xffff8800104f2d20 @offset=3360 fp=0xffff8800104f2bd0 [14925.114041] [14925.114041] Bytes b4 ffff8800104f2d10: 0a b1 de 00 01 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ [14925.114041] Object ffff8800104f2d20: 00 a9 38 83 ff ff ff ff ..8..... [14925.114041] Redzone ffff8800104f2d28: 00 00 00 00 cc cc cc cc ........ [14925.114041] Padding ffff8800104f2e68: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ [14925.114041] Pid: 17491, comm: trinity Tainted: G W 3.2.0-rc2-sasha-00146-gc729049-dirty #15 [14925.114041] Call Trace: [14925.114041] [<ffffffff8112c8f6>] ? print_section+0x38/0x3a [14925.114041] [<ffffffff8112ca21>] print_trailer+0x129/0x132 [14925.114041] [<ffffffff8112cd02>] check_bytes_and_report+0xb2/0xeb [14925.114041] [<ffffffff8115bacc>] ? __seq_open_private+0x31/0x5e [14925.114041] [<ffffffff8112d811>] check_object+0x4e/0x1ae [14925.114041] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [14925.114041] [<ffffffff8112e723>] free_debug_processing+0x96/0x1dc [14925.114041] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [14925.114041] [<ffffffff8112ec07>] __slab_free+0x35/0x1dc [14925.114041] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [14925.114041] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [14925.114041] [<ffffffff81626be3>] ? debug_check_no_obj_freed+0x12/0x17 [14925.114041] [<ffffffff8115ba7c>] ? seq_release_private+0x26/0x45 [14925.114041] [<ffffffff8113041f>] kfree+0xb6/0xbf [14925.114041] [<ffffffff81196f4b>] ? single_open_net+0x54/0x54 [14925.114041] [<ffffffff8115ba7c>] seq_release_private+0x26/0x45 [14925.114041] [<ffffffff81196f7d>] seq_release_net+0x32/0x3b [14925.114041] [<ffffffff8118dc6c>] proc_reg_release+0xd9/0xf6 [14925.114041] [<ffffffff811418cf>] fput+0x11e/0x1dc [14925.114041] [<ffffffff8113f3d8>] filp_close+0x6e/0x79 [14925.114041] [<ffffffff81089f17>] put_files_struct+0xcc/0x196 [14925.114041] [<ffffffff8108a074>] exit_files+0x46/0x4f [14925.114041] [<ffffffff8108a756>] do_exit+0x264/0x75c [14925.114041] [<ffffffff8104ca1b>] ? smp_apic_timer_interrupt+0x76/0x84 [14925.114041] [<ffffffff81b966b8>] ? retint_restore_args+0x13/0x13 [14925.114041] [<ffffffff8108ad01>] do_group_exit+0x83/0xb1 [14925.114041] [<ffffffff8108ad41>] sys_exit_group+0x12/0x16 [14925.114041] [<ffffffff81b96f52>] system_call_fastpath+0x16/0x1b [14925.114041] FIX kmalloc-8: Restoring 0xffff8800104f2d28-0xffff8800104f2d2b=0xcc [14925.114041] [15958.081391] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [15958.082012] CPU 1 [15958.082012] Pid: 15, comm: rcuc/1 Tainted: G W 3.2.0-rc2-sasha-00146-gc729049-dirty #15 [15958.082012] RIP: 0010:[<ffffffff810b305b>] [<ffffffff810b305b>] __lock_acquire+0xff/0xe50 [15958.082012] RSP: 0000:ffff880013c03cc8 EFLAGS: 00010002 [15958.082012] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800124daf60 RCX: 0000000000000000 [15958.082012] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880010b82568 [15958.082012] RBP: ffff880013c03d98 R08: 0000000000000002 R09: 0000000000000000 [15958.082012] R10: ffff880010b82568 R11: 0000000000000001 R12: ffff880010b82568 [15958.082012] R13: 0000000000000002 R14: 0000000000000000 R15: ffff880013c03f18 [15958.082012] FS: 0000000000000000(0000) GS:ffff880013c00000(0000) knlGS:0000000000000000 [15958.082012] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [15958.082012] CR2: 00007f9193a05c2c CR3: 0000000010735000 CR4: 00000000000406e0 [15958.082012] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [15958.082012] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [15958.082012] Process rcuc/1 (pid: 15, threadinfo ffff8800124e6000, task ffff8800124daf60) [15958.082012] Stack: [15958.082012] ffff880013dceb10 ffff8800124daf60 ffffffff00000000 0000000000000000 [15958.082012] ffff880010b82568 0000000000000082 ffff880000000000 ffffffff810b1d97 [15958.082012] ffff8800124daf60 ffff880013c03ee8 ffff880013c03df8 ffffffff816141ae [15958.082012] Call Trace: [15958.082012] <IRQ> [15958.082012] [<ffffffff810b1d97>] ? trace_hardirqs_on_caller+0x151/0x197 [15958.082012] [<ffffffff816141ae>] ? trace_hardirqs_on_thunk+0x3a/0x3f [15958.082012] [<ffffffff810b4255>] lock_acquire+0x8a/0xa7 [15958.082012] [<ffffffff81aa6314>] ? dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff810afac3>] ? arch_local_irq_restore+0x12/0x19 [15958.082012] [<ffffffff81b958b7>] _raw_spin_lock+0x3b/0x6e [15958.082012] [<ffffffff81aa6314>] ? dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff81aa6314>] dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff810915f1>] run_timer_softirq+0x1da/0x28c [15958.082012] [<ffffffff81091599>] ? run_timer_softirq+0x182/0x28c [15958.082012] [<ffffffff81aa62f4>] ? dn_neigh_elist+0x3a/0x3a [15958.082012] [<ffffffff8108c2e4>] __do_softirq+0xa4/0x14b [15958.082012] [<ffffffff81b9923c>] call_softirq+0x1c/0x30 [15958.082012] <EOI> [15958.082012] [<ffffffff8103525a>] do_softirq+0x62/0xb8 [15958.082012] [<ffffffff810e1711>] ? rcu_cpu_kthread+0x284/0x2b8 [15958.082012] [<ffffffff8108c1cb>] _local_bh_enable_ip+0xaf/0xe6 [15958.082012] [<ffffffff8108c233>] local_bh_enable+0xd/0xf [15958.082012] [<ffffffff810e1711>] rcu_cpu_kthread+0x284/0x2b8 [15958.082012] [<ffffffff810e148d>] ? rcu_do_batch.clone.24+0x1fe/0x1fe [15958.082012] [<ffffffff8109ee97>] kthread+0x9b/0xa3 [15958.082012] [<ffffffff810b1d97>] ? trace_hardirqs_on_caller+0x151/0x197 [15958.082012] [<ffffffff81b99144>] kernel_thread_helper+0x4/0x10 [15958.082012] [<ffffffff81b966b8>] ? retint_restore_args+0x13/0x13 [15958.082012] [<ffffffff8109edfc>] ? kthread_flush_work_fn+0xf/0xf [15958.082012] [<ffffffff81b99140>] ? gs_change+0x13/0x13 [15958.082012] Code: 8d 40 ff ff ff 4c 89 95 50 ff ff ff 45 31 f6 e8 23 fc ff ff 44 8b 8d 40 ff ff ff 48 85 c0 4c 8b 95 50 ff ff ff 0f 84 e4 0c 00 00 <f0> ff 80 98 01 00 00 44 8b bb d0 08 00 00 83 3d 64 27 74 01 00 [15958.082012] RIP [<ffffffff810b305b>] __lock_acquire+0xff/0xe50 [15958.082012] RSP <ffff880013c03cc8> [15958.082012] ---[ end trace 21ee6c8ed26977a8 ]--- [15958.082012] Kernel panic - not syncing: Fatal exception in interrupt [15958.082012] Pid: 15, comm: rcuc/1 Tainted: G D W 3.2.0-rc2-sasha-00146-gc729049-dirty #15 [15958.082012] Call Trace: [15958.082012] <IRQ> [<ffffffff81b930f3>] panic+0x96/0x1c3 [15958.082012] [<ffffffff81036626>] oops_end+0xcf/0xdf [15958.082012] [<ffffffff8103677c>] die+0x55/0x61 [15958.082012] [<ffffffff8103417b>] do_general_protection+0x12e/0x136 [15958.082012] [<ffffffff81b966e8>] ? restore_args+0x30/0x30 [15958.082012] [<ffffffff81b96935>] general_protection+0x25/0x30 [15958.082012] [<ffffffff810b305b>] ? __lock_acquire+0xff/0xe50 [15958.082012] [<ffffffff810b2fcb>] ? __lock_acquire+0x6f/0xe50 [15958.082012] [<ffffffff810b1d97>] ? trace_hardirqs_on_caller+0x151/0x197 [15958.082012] [<ffffffff816141ae>] ? trace_hardirqs_on_thunk+0x3a/0x3f [15958.082012] [<ffffffff810b4255>] lock_acquire+0x8a/0xa7 [15958.082012] [<ffffffff81aa6314>] ? dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff810afac3>] ? arch_local_irq_restore+0x12/0x19 [15958.082012] [<ffffffff81b958b7>] _raw_spin_lock+0x3b/0x6e [15958.082012] [<ffffffff81aa6314>] ? dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff81aa6314>] dn_slow_timer+0x20/0x108 [15958.082012] [<ffffffff810915f1>] run_timer_softirq+0x1da/0x28c [15958.082012] [<ffffffff81091599>] ? run_timer_softirq+0x182/0x28c [15958.082012] [<ffffffff81aa62f4>] ? dn_neigh_elist+0x3a/0x3a [15958.082012] [<ffffffff8108c2e4>] __do_softirq+0xa4/0x14b [15958.082012] [<ffffffff81b9923c>] call_softirq+0x1c/0x30 [15958.082012] <EOI> [<ffffffff8103525a>] do_softirq+0x62/0xb8 [15958.082012] [<ffffffff810e1711>] ? rcu_cpu_kthread+0x284/0x2b8 [15958.082012] [<ffffffff8108c1cb>] _local_bh_enable_ip+0xaf/0xe6 [15958.082012] [<ffffffff8108c233>] local_bh_enable+0xd/0xf [15958.082012] [<ffffffff810e1711>] rcu_cpu_kthread+0x284/0x2b8 [15958.082012] [<ffffffff810e148d>] ? rcu_do_batch.clone.24+0x1fe/0x1fe [15958.082012] [<ffffffff8109ee97>] kthread+0x9b/0xa3 [15958.082012] [<ffffffff810b1d97>] ? trace_hardirqs_on_caller+0x151/0x197 [15958.082012] [<ffffffff81b99144>] kernel_thread_helper+0x4/0x10 [15958.082012] [<ffffffff81b966b8>] ? retint_restore_args+0x13/0x13 [15958.082012] [<ffffffff8109edfc>] ? kthread_flush_work_fn+0xf/0xf [15958.082012] [<ffffffff81b99140>] ? gs_change+0x13/0x13 [15958.082012] Rebooting in 1 seconds.. # KVM session ended normally. Please let me know if theres anything I can do to help debugging it. -- Sasha. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>