From: Avi Kivity <avi@redhat.com>
To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Eric B Munson <emunson@mgebm.net>,
mingo@redhat.com, hpa@zytor.com, ryanh@linux.vnet.ibm.com,
aliguori@us.ibm.com, mtosatti@redhat.com,
jeremy.fitzhardinge@citrix.com, kvm@vger.kernel.org,
linux-arch@vger.kernel.org, x86@kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/4 V10] Add ioctl for KVMCLOCK_GUEST_STOPPED
Date: Mon, 30 Jan 2012 19:11:25 +0200 [thread overview]
Message-ID: <4F26CF3D.4070001@redhat.com> (raw)
In-Reply-To: <4F26C2EC.5070303@siemens.com>
On 01/30/2012 06:18 PM, Jan Kiszka wrote:
> >
> > This looks racy. The vcpu can remove its kvmclock concurrently with
> > this access, and src will be NULL.
>
> There is no race here (src is member of the vcpu), but arch.time might
> have become invalid. KVM_REQ_CLOCK_UPDATE instead of mark_page_dirty
> would indeed be the way to go. Trivial solution, I would say.
>
> However, the concept of "guest stopped" has VM, not VCPU scope.
We're not stopping the guest here, just setting a flag in kvmclock,
which certainly is a per-vcpu thing.
> That
> makes the call more appropriate as a VM ioctl. If that thing should
> really become per-vcpu, at least call it KVMCLOCK_VCPU_STOPPED.
>
All current ioctls start with KVM_. Maybe KVM_KVMCLOCK_CTRL?
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2012-01-30 17:11 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1326825641-15765-1-git-send-email-emunson@mgebm.net>
2012-01-17 18:40 ` [PATCH 1/4 V10] Add flag to indicate that a vm was stopped by the host Eric B Munson
2012-01-17 18:40 ` [PATCH 2/4 V10] Add functions to check if the host has stopped the vm Eric B Munson
2012-01-17 18:40 ` [PATCH 3/4 V10] Add ioctl for KVMCLOCK_GUEST_STOPPED Eric B Munson
2012-01-30 15:07 ` Avi Kivity
2012-01-30 15:11 ` Avi Kivity
2012-01-30 15:33 ` Eric B Munson
2012-01-30 15:32 ` Eric B Munson
2012-01-30 15:49 ` Avi Kivity
2012-01-30 16:01 ` Eric B Munson
2012-01-30 16:18 ` Jan Kiszka
2012-01-30 17:11 ` Avi Kivity [this message]
2012-01-17 18:40 ` [PATCH 4/4 V10] Add check for suspended vm in softlockup detector Eric B Munson
2012-01-27 20:45 ` [PATCH 0/4 V10] Avoid soft lockup message when KVM is stopped by host Eric B Munson
2012-01-30 15:08 ` Avi Kivity
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=4F26CF3D.4070001@redhat.com \
--to=avi@redhat.com \
--cc=aliguori@us.ibm.com \
--cc=emunson@mgebm.net \
--cc=hpa@zytor.com \
--cc=jan.kiszka@siemens.com \
--cc=jeremy.fitzhardinge@citrix.com \
--cc=kvm@vger.kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=mtosatti@redhat.com \
--cc=ryanh@linux.vnet.ibm.com \
--cc=x86@kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.