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Date: Tue, 18 Feb 2014 11:23:02 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 3/3] qtest: kill QEMU process on g_assert()
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To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, Stefan Hajnoczi <stefanha@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel@nongnu.org, Markus Armbruster <armbru@redhat.com>, Anthony Liguori <aliguori@amazon.com>, Andreas Faerber <afaerber@suse.de>

Il 18/02/2014 11:17, Daniel P. Berrange ha scritto:
>>> > >Yes, SIGABRT is synchronous for all purposes.  So the only danger is
>>> > >that g_string_free() or g_free() could fail while we're in
>>> > >g_assert(false).  But they don't, which makes sense because they are
>>> > >totally unrelated to g_assert() and therefore can handle re-entrancy.
>> >
>> > If malloc aborts due to a double free or other similar problem, you
>> > may risk reentering it.
> If you register the custom SIGABRT handler with sigaction + SA_RESETHAND
> then you'd avoid the re-entrancy risk, since a cascading SIGABRT would
> get handled by the system default handler, which would immediately
> terminate the process.

I meant reentering malloc.

Paolo