From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: KVM_GET_SUPPORTED_CPUID returning -E2BIG
Date: Sun, 08 May 2011 11:56:13 +0300
Message-ID: <4DC65AAD.3050003@redhat.com>
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Cc: kvm <kvm@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Pekka Enberg <penberg@kernel.org>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Asias He <asias.hejun@gmail.com>,
	Prasad Joshi <prasadjoshi124@gmail.com>
To: Sasha Levin <levinsasha928@gmail.com>
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On 05/08/2011 08:15 AM, Sasha Levin wrote:
> Hello,
>
> I'm seeing a case where KVM tools occasionally fails with the following
> error message: "KVM_GET_SUPPORTED_CPUID failed: Argument list too long",
> which means that we get -E2BIG back from KVM_GET_SUPPORTED_CPUID.
>
> Why would it happen if we pass KVM_MAX_CPUID_ENTRIES as the max number
> of entries (in the nent field of struct kvm_cpuid2)?

KVM_MAX_CPUID_ENTRIES is a private define, not exported to userspace 
(since it can change).

> Also, Why would it happen randomly and not each time the code is run?

Probably you have some bug.  E2BIG is returned when nent is smaller than 
the number of entries returned (which only depends on the host cpu type).

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