[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v6 01/10] qom: add helpers for UserCreatable obj
From: |
Markus Armbruster |
Subject: |
Re: [Qemu-devel] [PATCH v6 01/10] qom: add helpers for UserCreatable object types |
Date: |
Wed, 27 Apr 2016 15:37:21 +0200 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) |
Markus Armbruster <address@hidden> writes:
> This commit regresses error message quality from
>
> $ qemu-system-x86_64 -nodefaults -display none -object
> secret,id=sec0,data=letmein,format=raw,foo=bar
> qemu-system-x86_64: -object
> secret,id=sec0,data=letmein,format=raw,foo=bar: Property '.foo' not found
>
> to just
>
> qemu-system-x86_64: Property '.foo' not found
>
> Clue: cur_loc points to garbage.
>
> (gdb) p cur_loc
> $1 = (Location *) 0x7fffffffdc10
> (gdb) p *cur_loc
> $2 = {kind = (unknown: 4294958128), num = 32767,
> ptr = 0x555555b804a2 <error_report_err+44>, prev = 0x5555565d2770
> <std_loc>}
>
> Looks like cur_loc is dangling. Happens when you forget to loc_pop() a
> Location before it dies. This one is on the stack.
>
> *Might* be release critical.
>
> For comparison, this is how it looks before the patch:
>
> (gdb) p cur_loc
> $1 = (Location *) 0x7fffffffdc10
> (gdb) p *cur_loc
> $2 = {kind = LOC_CMDLINE, num = 2, ptr = 0x7fffffffe018, prev =
> 0x5555565d2770 <std_loc>}
>
> Reported-by: Eric Blake <address@hidden>
I think I nailed it. Preparing patches...