From: Gleb Natapov <gleb@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>,
Daniel Gollub <gollub@b1-systems.de>,
"Daniel P. Berrange" <berrange@redhat.com>,
kvm@vger.kernel.org, qemu-devel <qemu-devel@nongnu.org>
Subject: Re: [PATCH 0/2] Introduce panic hypercall
Date: Tue, 21 Jun 2011 09:04:28 +0300 [thread overview]
Message-ID: <20110621060428.GC491@redhat.com> (raw)
In-Reply-To: <4DFF8208.7060401@redhat.com>
On Mon, Jun 20, 2011 at 08:23:20PM +0300, Avi Kivity wrote:
> On 06/20/2011 08:13 PM, Jan Kiszka wrote:
> >> A watchdog has the advantage that is also detects lockups.
> >>
> >> In fact you could implement the panic device via the existing
> >> watchdogs. Simply program the timer for the minimum interval and
> >> *don't* service the interrupt. This would work for non-virt setups as
> >> well as another way to issue a reset.
> >
> >If you manage to bring down the other guest CPUs fast enough. Otherwise,
> >they may corrupt your crashdump before the host had a chance to collect
> >all pieces. Synchronous signaling to the hypervisor is a bit safer.
>
> You could NMI-IPI them. But I agree a synchronous signal is better
> (note it's not race-free itself).
>
But kexec/kdump has exactly same race, so this is at least not worse that
alternative.
--
Gleb.
next prev parent reply other threads:[~2011-06-21 6:04 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-20 13:38 [PATCH 0/2] Introduce panic hypercall Daniel Gollub
2011-06-20 13:38 ` [PATCH 1/2] Inroduce panic hypercall KVM_HC_PANIC (host) Daniel Gollub
2011-06-20 13:38 ` [PATCH 2/2] Call KVM_HC_PANIC if guest panics Daniel Gollub
2011-06-20 15:31 ` [PATCH 0/2] Introduce panic hypercall Avi Kivity
2011-06-20 15:38 ` Daniel P. Berrange
2011-06-20 15:45 ` Avi Kivity
2011-06-20 15:59 ` Jan Kiszka
2011-06-20 16:26 ` Daniel Gollub
2011-06-20 16:34 ` Avi Kivity
2011-06-20 17:13 ` Jan Kiszka
2011-06-20 17:23 ` Avi Kivity
2011-06-21 6:04 ` Gleb Natapov [this message]
2011-06-21 6:02 ` Gleb Natapov
2011-06-21 8:09 ` Avi Kivity
2011-06-21 8:41 ` Gleb Natapov
2011-06-21 8:56 ` Avi Kivity
2011-06-21 9:03 ` Gleb Natapov
2011-06-21 9:07 ` Avi Kivity
2011-06-21 9:30 ` shawn che
2011-06-20 19:28 ` Anthony Liguori
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110621060428.GC491@redhat.com \
--to=gleb@redhat.com \
--cc=avi@redhat.com \
--cc=berrange@redhat.com \
--cc=gollub@b1-systems.de \
--cc=jan.kiszka@siemens.com \
--cc=kvm@vger.kernel.org \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox