Message-ID: <508543DE.3080504@redhat.com>
Date: Mon, 22 Oct 2012 15:02:22 +0200
From: Avi Kivity <avi@redhat.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120911 Thunderbird/15.0.1
MIME-Version: 1.0
To: Gleb Natapov <gleb@redhat.com>
CC: Jan Kiszka <jan.kiszka@siemens.com>,
        Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH] KVM: x86: fix vcpu->mmio_fragments overflow
References: <20121022091615.GG29310@redhat.com> <50852972.305@linux.vnet.ibm.com> <20121022112314.GO29310@redhat.com> <50852F9C.9020808@siemens.com> <20121022114311.GQ29310@redhat.com> <508531E1.2030307@siemens.com> <508539A8.40404@redhat.com> <50853FF1.8010809@siemens.com> <20121022125301.GS29310@redhat.com> <5085423C.2020908@redhat.com> <20121022130102.GU29310@redhat.com>
In-Reply-To: <20121022130102.GU29310@redhat.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 756
Lines: 21

On 10/22/2012 03:01 PM, Gleb Natapov wrote:

>> It's time where the guest cannot take interrupts, and time in a high
>> priority guest thread that is spent processing low guest priority requests.
>> 
> Proposed fix has exactly same issue. Until all data is transfered to
> userspace no interrupt will be served.

For mmio_fragments that is okay.  It's the same guest instruction, and
it's still O(1).

It's not okay for general mmio coalescing.


-- 
error compiling committee.c: too many arguments to function
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/