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From: =?utf-8?Q?Llu=C3=ADs_Vilanova?= <vilanova@ac.upc.edu>
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Date: Mon, 16 Jan 2017 18:10:57 +0100
In-Reply-To: <20170109154439.GF30228@stefanha-x1.localdomain> (Stefan
	Hajnoczi's message of "Mon, 9 Jan 2017 15:44:39 +0000")
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Subject: Re: [Qemu-devel] [PATCH v4 3/6] hypertrace: [*-user] Add QEMU-side
 proxy to "guest_hypertrace" event
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To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, Daniel P Berrange <berrange@redhat.com>, Luiz Capitulino <lcapitulino@redhat.com>, Eric Blake <eblake@redhat.com>, Riku Voipio <riku.voipio@iki.fi>

Stefan Hajnoczi writes:

> On Mon, Dec 26, 2016 at 09:34:54PM +0100, Llu=C3=ADs Vilanova wrote:
[...]
>> +
>> +    } else {
>> +        /* proxy to next handler */
>> +        if (segv_next.sa_sigaction !=3D NULL) {
>> +            segv_next.sa_sigaction(signum, siginfo, sigctxt);
>> +        } else if (segv_next.sa_handler !=3D NULL) {
>> +            segv_next.sa_handler(signum);
>> +        }

> Is there a case when no signal handler was installed (i.e. default
> action)?

Sorry, in my previous email I meant no, there is none. If hypertrace is not
initialized, the segv handler will never be installed; otherwise segv_next =
will
always have one of the two values.


Thanks,
  Lluis