From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
Christian Borntraeger <christian.borntraeger@de.ibm.com>
Subject: Re: [PATCH 1/3] KVM: introduce kvm->created_vcpus
Date: Mon, 13 Jun 2016 16:43:06 +0200 [thread overview]
Message-ID: <20160613164306.760ba899.cornelia.huck@de.ibm.com> (raw)
In-Reply-To: <1465824332-10628-2-git-send-email-pbonzini@redhat.com>
On Mon, 13 Jun 2016 15:25:30 +0200
Paolo Bonzini <pbonzini@redhat.com> wrote:
> The race between creating the irqchip and the first VCPU is
> currently fixed by checking the presence of an irqchip before
> updating kvm->online_vcpus, and undoing the whole VCPU creation
> if someone created the irqchip in the meanwhile.
>
> Instead, introduce a new field in struct kvm that will count VCPUs
> under a mutex, without the atomic access and memory ordering that we
> need elsewhere to protect the vcpus array. This also plugs the race
> and is more easily applicable in all similar circumstances.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> include/linux/kvm_host.h | 8 ++++++++
> virt/kvm/kvm_main.c | 23 +++++++++++++++++------
> 2 files changed, 25 insertions(+), 6 deletions(-)
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
next prev parent reply other threads:[~2016-06-13 14:43 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-13 13:25 [PATCH 0/3] KVM: do not use kvm->online_vcpus to check "has one VCPU been created?" Paolo Bonzini
2016-06-13 13:25 ` [PATCH 1/3] KVM: introduce kvm->created_vcpus Paolo Bonzini
2016-06-13 14:43 ` Cornelia Huck [this message]
2016-06-13 13:25 ` [PATCH 2/3] KVM: remove kvm_vcpu_compatible Paolo Bonzini
2016-06-13 13:25 ` [PATCH 3/3] KVM: s390: use kvm->created_vcpus Paolo Bonzini
2016-06-13 14:36 ` Cornelia Huck
2016-06-13 13:33 ` [PATCH 0/3] KVM: do not use kvm->online_vcpus to check "has one VCPU been created?" Christian Borntraeger
2016-06-13 14:44 ` Cornelia Huck
2016-06-15 22:00 ` Paolo Bonzini
2016-06-16 7:30 ` Christian Borntraeger
2016-06-16 7:59 ` Cornelia Huck
2016-06-16 8:23 ` Paolo Bonzini
2016-06-16 8:07 ` Paolo Bonzini
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=20160613164306.760ba899.cornelia.huck@de.ibm.com \
--to=cornelia.huck@de.ibm.com \
--cc=christian.borntraeger@de.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
/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;
as well as URLs for NNTP newsgroup(s).