gdb core dump when analysing kernel core dump

[Thomas Klausner <tk%giga.or.at@localhost>]

Hi!

Recently I had a kernel panic, and got a core dump. Since I also had a
netbsd.gdb for that kernel, I thought I'd take a look.

fatal page fault in supervisor mode
trap type 6 code 0 rip ffffffff802eb4c2 cs 8 rflags 10282 cr2 58 ilevel 4 rsp fffffe813a43cf28
curlwp 0xfffffe882df2d420 pid 0.3 lowest kstack 0xfffffe813a4392c0
panic: trap
cpu0: Begin traceback...
vpanic() at netbsd:vpanic+0x13c
snprintf() at netbsd:snprintf
startlwp() at netbsd:startlwp
alltraps() at netbsd:alltraps+0x9e
usb_soft_intr() at netbsd:usb_soft_intr+0x1b
softint_dispatch() at netbsd:softint_dispatch+0xd3
DDB lost frame for netbsd:Xsoftintr+0x4f, trying 0xfffffe813a43cff0
Xsoftintr() at netbsd:Xsoftintr+0x4f
--- interrupt ---
0:
cpu0: End traceback...



(gdb) target kvm core
0xffffffff80675e85 in cpu_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at /archive/foreign/src/sys/arch/amd64/amd64/machdep.c:671
671                     dumpsys();
(gdb) bt
#0  0xffffffff80675e85 in cpu_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at /archive/foreign/src/sys/arch/amd64/amd64/machdep.c:671
#1  0xffffffff808ca514 in vpanic (fmt=fmt@entry=0xffffffff80dd8a2d "trap", ap=ap@entry=0xfffffe813a43cd10) at /archive/foreign/src/sys/kern/subr_prf.c:340
#2  0xffffffff808ca5cf in panic (fmt=fmt@entry=0xffffffff80dd8a2d "trap") at /archive/foreign/src/sys/kern/subr_prf.c:256
#3  0xffffffff80919747 in trap (frame=0xfffffe813a43ce30) at /archive/foreign/src/sys/arch/amd64/amd64/trap.c:298
#4  0xffffffff8010108e in alltraps ()
#5  0xffffffff802eb4c2 in ehci_check_qh_intr (ex=0xfffffe813bcef5c8, sc=0xfffffe813ba45008) at /archive/foreign/src/sys/dev/usb/ehci.c:855
#6  ehci_check_intr (ex=0xfffffe813bcef5c8, sc=0xfffffe813ba45008) at /archive/foreign/src/sys/dev/usb/ehci.c:812
#7  ehci_softintr (v=<optimized out>) at /archive/foreign/src/sys/dev/usb/ehci.c:782
#8  0xffffffff809a5bce in usb_soft_intr (arg=0xfffffe813ba45048) at /archive/foreign/src/sys/dev/usb/usb.c:1023
#9  0xffffffff8060c6a8 in softint_execute (l=<optimized out>, s=4, si=0xffff80023a50e230) at /archive/foreign/src/sys/kern/kern_softint.c:589
#10 softint_dispatch (Abort (core dumped) 


I.e., gdb dumps core after printing "#10 softing_dispatch ("

Here's the backtrace for the gdb core dump:

(gdb) bt
#0  0x00007f7ff510e73a in _lwp_kill () from /usr/lib/libc.so.12
#1  0x00007f7ff510e3c5 in abort () at /archive/foreign/src/lib/libc/stdlib/abort.c:74
#2  0x00000000005477e3 in amd64nbsd_trapframe_cache (this_frame=<optimized out>, this_cache=<optimized out>) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/amd64nbsd-tdep.c:168
#3  0x000000000054780f in amd64nbsd_trapframe_this_id (this_frame=<optimized out>, this_cache=<optimized out>, this_id=0x7f7febc29cb8) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/amd64nbsd-tdep.c:209
#4  0x00000000004ac6b8 in compute_frame_id (fi=0x7f7febc29c58) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/frame.c:452
#5  get_prev_frame_if_no_cycle (this_frame=this_frame@entry=0x7f7febc16d08) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/frame.c:1737
#6  0x00000000004ae0e3 in get_prev_frame_1 (this_frame=this_frame@entry=0x7f7febc16d08) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/frame.c:1910
#7  0x00000000004aebb5 in get_prev_frame (this_frame=this_frame@entry=0x7f7febc16d08) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/frame.c:2124
#8  0x000000000057ee55 in dwarf_expr_push_dwarf_reg_entry_value (ctx=0x7f7ff7b274a0, kind=CALL_SITE_PARAMETER_DWARF_REG, kind_u=..., deref_size=-1)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2loc.c:1201
#9  0x00000000005aee91 in execute_stack_op (ctx=ctx@entry=0x7f7ff7b274a0, op_ptr=0x7f7fef39f418 <error: Cannot access memory at address 0x7f7fef39f418>, 
    op_ptr@entry=0x7f7fef39f415 <error: Cannot access memory at address 0x7f7fef39f415>, op_end=op_end@entry=0x7f7fef39f419 <error: Cannot access memory at address 0x7f7fef39f419>)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2expr.c:1376
#10 0x00000000005af6b8 in dwarf_expr_eval (ctx=ctx@entry=0x7f7ff7b274a0, addr=addr@entry=0x7f7fef39f415 <error: Cannot access memory at address 0x7f7fef39f415>, len=len@entry=4)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2expr.c:364
#11 0x000000000057b775 in dwarf2_evaluate_loc_desc_full (type=0x7f7febc900e8, frame=frame@entry=0x7f7febc16d08, data=0x7f7fef39f415 <error: Cannot access memory at address 0x7f7fef39f415>, size=4, 
    per_cu=0x7f7ff5f13be0, byte_offset=byte_offset@entry=0) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2loc.c:2251
#12 0x000000000057f45c in dwarf2_evaluate_loc_desc (per_cu=<optimized out>, size=<optimized out>, data=<optimized out>, frame=0x7f7febc16d08, type=<optimized out>)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2loc.c:2431
#13 loclist_read_variable (symbol=0x7f7febcc7628, frame=0x7f7febc16d08) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/dwarf2loc.c:4092
#14 0x0000000000477161 in default_read_var_value (var=0x7f7febcc7628, frame=0x7f7febc16d08) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/findvar.c:439
#15 0x000000000040a55d in read_frame_arg (sym=sym@entry=0x7f7febcc7628, frame=frame@entry=0x7f7febc16d08, argp=argp@entry=0x7f7fffffce90, entryargp=entryargp@entry=0x7f7fffffceb0)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:345
#16 0x000000000040aeaa in print_frame_args (func=<optimized out>, frame=frame@entry=0x7f7febc16d08, num=num@entry=-1, stream=0x7f7ff7b297c0) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:672
#17 0x000000000040b54b in print_frame (frame=frame@entry=0x7f7febc16d08, print_level=print_level@entry=1, print_what=print_what@entry=LOCATION, print_args=print_args@entry=1, sal=...)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:1203
#18 0x000000000040bb00 in print_frame_info (frame=frame@entry=0x7f7febc16d08, print_level=print_level@entry=1, print_what=print_what@entry=LOCATION, print_args=print_args@entry=1, 
    set_current_sal=set_current_sal@entry=0) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:855
#19 0x000000000040c131 in backtrace_command_1 (count_exp=count_exp@entry=0x0, show_locals=0, no_filters=0, from_tty=from_tty@entry=1) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:1814
#20 0x000000000040c504 in backtrace_command (arg=0x0, from_tty=1) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/stack.c:1911
#21 0x00000000004b503c in execute_command (p=<optimized out>, p@entry=0x7f7ff7b26080 "bt", from_tty=1) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/top.c:468
#22 0x000000000050de44 in command_handler (command=0x7f7ff7b26080 "bt") at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-top.c:435
#23 0x000000000050e23a in command_line_handler (rl=<optimized out>) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-top.c:632
#24 0x000000000065ca8e in rl_callback_read_char () at /archive/foreign/src/external/gpl3/gdb/dist/readline/callback.c:220
#25 0x000000000050de9b in rl_callback_read_char_wrapper (client_data=<optimized out>) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-top.c:164
#26 0x000000000050ef99 in process_event () at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-loop.c:342
#27 0x000000000050f268 in gdb_do_one_event () at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-loop.c:406
#28 0x000000000050f44a in start_event_loop () at /archive/foreign/src/external/gpl3/gdb/dist/gdb/event-loop.c:431
#29 0x00000000004063fd in captured_command_loop (data=data@entry=0x0) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/main.c:267
#30 0x0000000000490f6c in catch_errors (func=func@entry=0x4063ea <captured_command_loop>, func_args=func_args@entry=0x0, errstring=errstring@entry=0x6b90f7 "", mask=mask@entry=RETURN_MASK_ALL)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/exceptions.c:524
#31 0x00000000004072d4 in captured_main (data=data@entry=0x7f7fffffd530) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/main.c:1067
#32 0x0000000000490f6c in catch_errors (func=func@entry=0x406685 <captured_main>, func_args=func_args@entry=0x7f7fffffd530, errstring=errstring@entry=0x6b90f7 "", mask=mask@entry=RETURN_MASK_ALL)
    at /archive/foreign/src/external/gpl3/gdb/dist/gdb/exceptions.c:524
#33 0x00000000004074ef in gdb_main (args=args@entry=0x7f7fffffd530) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/main.c:1076
#34 0x000000000069294d in main (argc=<optimized out>, argv=<optimized out>) at /archive/foreign/src/external/gpl3/gdb/dist/gdb/gdb.c:34

Should I file a bug report? What to include?
 Thomas