From: Paolo Bonzini <pbonzini@redhat.com>
To: "Zhang, Yang Z" <yang.z.zhang@intel.com>,
Zhang Haoyu <zhanghy@sangfor.com>, kvm <kvm@vger.kernel.org>
Cc: Alex Williamson <alex.williamson@redhat.com>,
Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
"Michael S.Tsirkin" <mst@redhat.com>,
Gleb Natapov <gleb@cloudius-systems.com>
Subject: Re: [question] lots of interrupts injected to vm when pressing some key w/o releasing
Date: Tue, 25 Nov 2014 10:49:40 +0100 [thread overview]
Message-ID: <547450B4.6010909@redhat.com> (raw)
In-Reply-To: <A9667DDFB95DB7438FA9D7D576C3D87E0ABF0FE3@SHSMSX104.ccr.corp.intel.com>
On 25/11/2014 04:15, Zhang, Yang Z wrote:
> > The IRR register means an interrupt was received and not serviced yet,
> > similar to the LAPIC or PIC register. It is not the same thing as the
> > interrupt line level (it happens to be for level-triggered interrupts).
>
> Yes, but commit(0bc830b05) changes the behavior: before it ,
> ioapic->irr is cleared only when userspace lower the irq level. With it,
> it is cleared after the edge interrupt is serviced by ioapic. As you
> mentioned below, if QEMU tried to set a line twice, than there will be
> two interrupts for guest which only one interrupt before commit(0bc830b05).
Indeed, but that shouldn't happen. It would be a QEMU bug, since the
all-QEMU implementation of the ioapic is doing the same as commit 0bc830b05.
Paolo
next prev parent reply other threads:[~2014-11-25 9:50 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-20 2:20 [question] lots of interrupts injected to vm when pressing some key w/o releasing Zhang Haoyu
2014-11-20 6:19 ` Paolo Bonzini
2014-11-20 6:59 ` [question] lots of interrupts injected to vm when pressing somekey " Zhang Haoyu
2014-11-20 7:06 ` Gleb Natapov
2014-11-24 8:58 ` [question] lots of interrupts injected to vm when pressingsomekey " Zhang Haoyu
[not found] ` <A9667DDFB95DB7438FA9D7D576C3D87E0ABEF25B@SHSMSX104.ccr.corp.intel.com>
2014-11-21 22:31 ` [question] lots of interrupts injected to vm when pressing some key " Paolo Bonzini
[not found] ` <A9667DDFB95DB7438FA9D7D576C3D87E0ABF0FE3@SHSMSX104.ccr.corp.intel.com>
2014-11-25 9:49 ` Paolo Bonzini [this message]
[not found] ` <A9667DDFB95DB7438FA9D7D576C3D87E0ABF396A@SHSMSX104.ccr.corp.intel.com>
2014-12-03 15:42 ` Paolo Bonzini
2014-12-15 9:39 ` Zhang Haoyu
2014-12-15 9:40 ` Paolo Bonzini
2014-11-24 12:17 ` Zhang Haoyu
2014-11-24 12:25 ` Paolo Bonzini
2014-11-25 1:54 ` [question] lots of interrupts injected to vm when pressing somekey " Zhang Haoyu
2014-11-25 7:02 ` Paolo Bonzini
2014-11-25 11:20 ` Zhang Haoyu
2014-11-25 13:52 ` Paolo Bonzini
[not found] ` <201411261511537876936@sangfor.com>
[not found] ` <A9667DDFB95DB7438FA9D7D576C3D87E0ABF2A95@SHSMSX104.ccr.corp.intel.com>
2014-11-27 7:20 ` [question] lots of interrupts injected to vm when pressing some key " Zhang Haoyu
[not found] ` <A9667DDFB95DB7438FA9D7D576C3D87E0ABF2C24@SHSMSX104.ccr.corp.intel.com>
2014-11-27 8:54 ` Zhang Haoyu
2014-11-28 8:27 ` Wanpeng Li
2014-11-28 9:44 ` Zhang Haoyu
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=547450B4.6010909@redhat.com \
--to=pbonzini@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=gleb@cloudius-systems.com \
--cc=kvm@vger.kernel.org \
--cc=mst@redhat.com \
--cc=xiaoguangrong@linux.vnet.ibm.com \
--cc=yang.z.zhang@intel.com \
--cc=zhanghy@sangfor.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 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.