Frederic Weisbecker wrote:
On Thu, Aug 13, 2009 at 04:57:20PM -0400, Masami Hiramatsu wrote:This script tests kprobes to probe on all symbols in the kernel and finds symbols which must be blacklisted. Usage ----- kprobestest [-s SYMLIST] [-b BLACKLIST] [-w WHITELIST] Run stress test. If SYMLIST file is specified, use it as an initial symbol list (This is useful for verifying white list after diagnosing all symbols). kprobestest cleanup Cleanup all lists How to Work ----------- This tool list up all symbols in the kernel via /proc/kallsyms, and sorts it into groups (each of them including 64 symbols in default). And then, it tests each group by using kprobe-tracer. If a kernel crash occurred, that group is moved into 'failed' dir. If the group passed the test, this script moves it into 'passed' dir and saves kprobe_profile into 'passed/profiles/'. After testing all groups, all 'failed' groups are merged and sorted into smaller groups (divided by 4, in default). And those are tested again. This loop will be repeated until all group has just 1 symbol. Finally, the script sorts all 'passed' symbols into 'tested', 'untested', and 'missed' based on profiles. Note ---- - This script just gives us some clues to the blacklisted functions. In some cases, a combination of probe points will cause a problem, but each of them doesn't cause the problem alone. Thank you,This script makes my x86-64 dual core easily and hardly locking-up on the 1st batch of symbols to test. I have one sym list in the failed and unset directories: int_very_careful int_signal int_restore_rest stub_clone stub_fork stub_vfork stub_sigaltstack stub_iopl ptregscall_common stub_execve stub_rt_sigreturn irq_entries_start common_interrupt ret_from_intr exit_intr retint_with_reschedule retint_check retint_swapgs retint_restore_args restore_args irq_return retint_careful retint_signal retint_kernel irq_move_cleanup_interrupt reboot_interrupt apic_timer_interrupt generic_interrupt invalidate_interrupt0 invalidate_interrupt1 invalidate_interrupt2 invalidate_interrupt3 invalidate_interrupt4 invalidate_interrupt5 invalidate_interrupt6 invalidate_interrupt7 threshold_interrupt thermal_interrupt mce_self_interrupt call_function_single_interrupt call_function_interrupt reschedule_interrupt error_interrupt spurious_interrupt perf_pending_interrupt divide_error overflow bounds invalid_op device_not_available double_fault coprocessor_segment_overrun invalid_TSS segment_not_present spurious_interrupt_bug coprocessor_error alignment_check simd_coprocessor_error native_load_gs_index gs_change kernel_thread child_rip kernel_execve call_softirq I don't have a crash log because I was running with X. But it also happened with other batch of symbols.
Thank you for reporting, here, I also have a result tested on KVM@x86-64. native_read_tscp native_read_msr_safe native_read_msr_amd_safe native_write_msr_safe vmalloc_fault spurious_fault search_exception_tables notify_die trace_hardirqs_off_caller ident_complete lock_acquire lock_release bad_address secondary_startup_64 stack_start bad_address restore_args irq_return restore trace_hardirqs_off_thunk init_level4_pgt level3_ident_pgt level3_kernel_pgt level2_fixmap_pgt _text startup_64 level1_fixmap_pgt level2_ident_pgt level2_kernel_pgt level2_spare_pgt native_get_debugreg native_set_debugreg native_set_iopl_mask native_load_sp0 debug_show_all_locks debug_check_no_locks_held valid_state mark_lock mark_held_locks lockdep_trace_alloc trace_softirqs_on trace_hardirqs_on_caller __down_write __down_read trace_hardirqs_on_thunk lockdep_sys_exit_thunk Most of them can be fixed just by adding __kprobes. Some of them which are already in the another section, kprobes should check the symbols are in the section.
The problem is that I don't have any serial line in this box then I can't catch any crash log. My K7 testbox also died in my arms this afternoon. But I still have two other testboxes (one P2 and one P3), hopefully I could reproduce the problem in these boxes in which I can connect a serial line.
Thank you for helping me to find it!
I've pushed your patches in the following git tree: git://git.kernel.org/pub/scm/linux/kernel/git/fgrederic/random-tracing.git \ tracing/kprobes So you can send patches on top of this one.
Great! I've found another trivial bugs, so I'll fix those on it. Thank you, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@xxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
