Unfortunately I received 2 other kdumps from the same user and it looks like that other 2 kdumps were happening because of a NULL dereference (3.2.0-79). I asked them to test latest 3.2 kernel + the fix I commented above.
User still faced kdumps with latest 3.2 but only with khungtask complaining about soft lockups. A first look into the dumps showed a lock contention: crash> bt ffff883f70c78000 PID: 41940 TASK: ffff883f70c78000 CPU: 13 COMMAND: "java" #0 [ffff883f69093d98] __schedule at ffffffff81666f4a #1 [ffff883f69093e20] schedule at ffffffff816675cf #2 [ffff883f69093e30] rwsem_down_failed_common at ffffffff8166940d #3 [ffff883f69093ea0] rwsem_down_write_failed at ffffffff816694c3 #4 [ffff883f69093eb0] call_rwsem_down_write_failed at ffffffff8131fb43 #5 [ffff883f69093f10] sys_mprotect at ffffffff811488f0 #6 [ffff883f69093f80] system_call_fastpath at ffffffff81671c62 RIP: 00007f1adc172cc7 RSP: 00007f1adcc89c60 RFLAGS: 00010297 RAX: 000000000000000a RBX: ffffffff81671c62 RCX: 00000000ef038c60 RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007f1ad49bc000 RBP: 0000000000002010 R8: 00000000009be000 R9: 0000000000000000 R10: 00000000009bc000 R11: 0000000000000206 R12: 0000000000000ac0 R13: 00007f1ad49bb540 R14: 0000000000002000 R15: 00007f1ad4000078 ORIG_RAX: 000000000000000a CS: 0033 SS: 002b on the task monitored by khungtask thread. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1534413 Title: Precise: lockup during fadvise syscall with POSIX_FADV_DONTNEED To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1534413/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
