Re: [Qemu-devel] Signal management in qemu-user

["Andreas Färber" <afaerber@suse.de>]

Am 17.05.2012 15:42, schrieb Peter Maydell:
> On 17 May 2012 14:33, Andreas Färber <afaerber@suse.de> wrote:
>> Am 17.05.2012 11:23, schrieb Alex Barcelo:
>>> Running it in a i386 machine works and gives an output of "0x0d\n0x20".
>>> Running it in a qemu-i386 segfaults. Because the self-modifying code
>>> raises a SIGSEGV in the qemu (I understand that it is the method used by
>>> qemu to handle self-modifying code). But the sigprocmask disables the
>>> SIGSEGV and the qemu-user... does nothing to avoid it. So the SIGSEGV is
>>> unmanaged and breaks the program.
>>
>> Alex has the following SIGSEGV workaround queued for our openSUSE package:
>> http://repo.or.cz/w/qemu/agraf.git/commit/0760e24b52ff20a328f168ed23b52c9b9c0fd28f
>>
>> Don't know if it fixes your specific problem.
> 
> No, that's a different issue, see the analysis here:
>  http://lists.gnu.org/archive/html/qemu-devel/2012-02/msg02868.html
> In that case an internal-to-QEMU allocation fails (because the guest
> imposes a severe rlimit), we don't handle it very well and die
> horribly. The commit you link to above is a sticking plaster on
> the problem and definitely not OK for master.

Note the term "workaround". :-)

/-F

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