[Crash-utility] crash crashes reading qemu dump files

[Andi Kleen]

So I wanted to use crash to look at a dump from a qemu KVM guest
I write a dump file from the qemu console with

dump-guest-core foo

Then I do on the host

crash vmlinux foo
...
   <segmentation violation in gdb>

In gdb I see it seems to jump to 0

(gdb) p $pc
$1 = (void (*)()) 0x0
(gdb) bt
#0  0x0000000000000000 in ?? ()
#1  0x000000000073707a in ui_file_write (length_buf=1,
buf=0x7fffffffbaaf "N", file=<optimized out>) at ui-file.c:224
#2  tee_file_write (file=<optimized out>, buf=0x7fffffffbaaf "N",
length_buf=1) at ui-file.c:758
#3  0x00000000007337d6 in fputc_unfiltered (stream=0x126de20,
c=<optimized out>) at utils.c:2209
#4  fputs_maybe_filtered (linebuffer=linebuffer at entry=0x1534a00 "No
symbol \"task_struct\" in current context.\n", 
    stream=stream at entry=0x126de20, filter=1) at utils.c:2126
#5  0x00000000007339b0 in vfprintf_maybe_filtered (stream=0x126de20,
format=format at entry=0x9db4b5 "%s\n", 
    args=args at entry=0x7fffffffbaf8, filter=1, filter=1) at utils.c:2332
#6  0x0000000000734a4c in vfprintf_filtered (args=0x7fffffffbaf8,
format=0x9db4b5 "%s\n", stream=<optimized out>) at utils.c:2340
#7  fprintf_filtered (stream=<optimized out>,
format=format at entry=0x9db4b5 "%s\n") at utils.c:2392
#8  0x0000000000676f67 in throw_exception (exception=...) at
exceptions.c:234
#9  0x0000000000677219 in throw_it (reason=reason at entry=RETURN_ERROR,
error=error at entry=GENERIC_ERROR, fmt=<optimized out>, 
    ap=ap at entry=0x7fffffffbc48) at exceptions.c:434
#10 0x0000000000677436 in throw_verror (error=error at entry=GENERIC_ERROR,
fmt=<optimized out>, ap=ap at entry=0x7fffffffbc48)
    at exceptions.c:440
#11 0x00000000007323d4 in error (string=<optimized out>) at utils.c:717
#12 0x00000000005ea1a3 in c_parse_internal () at c-exp.y:862
#13 0x00000000005ea4f9 in c_parse () at c-exp.y:3064
#14 0x00000000006a2fe1 in parse_exp_in_context
(stringptr=stringptr at entry=0x7fffffffda18, pc=pc at entry=0,
block=block at entry=0x0, 
    comma=comma at entry=0, out_subexp=out_subexp at entry=0x0,
    void_context_p=0) at parse.c:1234
#15 0x00000000006a31e5 in parse_exp_1
(stringptr=stringptr at entry=0x7fffffffda68, pc=pc at entry=0,
block=block at entry=0x0, 
    comma=comma at entry=0) at parse.c:1136
#16 0x00000000006a3239 in parse_expression (string=0x8739b0
"task_struct") at parse.c:1279
#17 0x000000000064b270 in gdb_get_datatype (req=0xe61620 <shared_bufs>)
at symtab.c:5330
#18 gdb_command_funnel (req=req at entry=0xe61620 <shared_bufs>) at
symtab.c:5208
#19 0x00000000004ddc45 in gdb_interface (req=req at entry=0xe61620
<shared_bufs>) at gdb_interface.c:397
#20 0x00000000004de102 in gdb_session_init () at gdb_interface.c:244
#21 0x0000000000466c14 in main_loop () at main.c:637
#22 0x0000000000678e83 in captured_command_loop (data=data at entry=0x0) at
main.c:258
#23 0x000000000067772a in catch_errors (func=func at entry=0x678e70
<captured_command_loop>, func_args=func_args at entry=0x0, 
    errstring=errstring at entry=0x8b201f "", mask=mask at entry=6) at
    exceptions.c:557
#24 0x0000000000679e16 in captured_main (data=data at entry=0x7fffffffde00)
at main.c:1064
#25 0x000000000067772a in catch_errors (func=func at entry=0x679150
<captured_main>, func_args=func_args at entry=0x7fffffffde00, 
    errstring=errstring at entry=0x8b201f "", mask=mask at entry=6) at
    exceptions.c:557
#26 0x000000000067a177 in gdb_main (args=0x7fffffffde00) at main.c:1079
#27 gdb_main_entry (argc=<optimized out>,
argv=argv at entry=0x7fffffffdf58) at main.c:1099
#28 0x00000000004dce84 in gdb_main_loop (argc=<optimized out>,
argc at entry=3, argv=argv at entry=0x7fffffffdf58) at gdb_interface.c:76
#29 0x000000000046549f in main (argc=3, argv=0x7fffffffdf58) at
main.c:613

Environment:
Linux 3.11, current mainline linux (same result)

FC19, qemu-system-x86-1.4.2-12.fc19.x86_64

Known problem?

-Andi

-- 
ak at linux.intel.com -- Speaking for myself only