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From: Avi Kivity <avi@qumranet.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: kvm-devel <kvm-devel@lists.sourceforge.net>
Subject: Re: KVM: kvm_vcpu_block task state race
Date: Sun, 11 May 2008 17:26:06 +0300	[thread overview]
Message-ID: <482701FE.2000707@qumranet.com> (raw)
In-Reply-To: <20080509192208.GA13579@dmt>

Marcelo Tosatti wrote:
>> The best practice is to issue all vcpu ioctls from the thread that 
>> created the vcpu; this becomes mandatory if we ever switch to a syscall 
>> interface and remove the mutex.
>>     
>
> For things like register dumps I don't believe its worthwhile. Much
> simpler to stop the vcpu with SIG_IPI, retrieve registers, and run it
> again (now that you mention the busy-spin, it is broken right now, if a
> vcpu is spinning without exiting to userspace).
>
> So do you want to give wait_event_interruptible() a try or wait for that
> change until userspace never issues vcpu ioctl's to a possibly busy vcpu
> (and go with the patch above)?
>   

Do we have anything critical that issues vcpu ioctls outside its 
thread?  While I much prefer wait_event_interruptible(), I don't want to 
break existing userspace.

-- 
error compiling committee.c: too many arguments to function


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  parent reply	other threads:[~2008-05-11 14:26 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-08 22:47 KVM: kvm_vcpu_block task state race Marcelo Tosatti
2008-05-09  7:40 ` Avi Kivity
2008-05-09 14:21   ` Marcelo Tosatti
2008-05-09 15:09     ` Avi Kivity
2008-05-09 19:22       ` Marcelo Tosatti
2008-05-09 19:27         ` Marcelo Tosatti
2008-05-11 14:24           ` Avi Kivity
2008-05-11 14:26         ` Avi Kivity [this message]
2008-05-14  5:21           ` Marcelo Tosatti
2008-05-14  7:55             ` Avi Kivity

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