From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@qumranet.com>
Subject: Re: [PATCH] kvm-userspace: fix memslot assignment
Date: Thu, 31 Jul 2008 14:24:13 +0300
Message-ID: <4891A0DD.5000503@qumranet.com>
References: <200807251738.29171.borntraeger@de.ibm.com> <200807281855.04681.borntraeger@de.ibm.com> <488F18B9.1010700@qumranet.com> <200807311001.07426.borntraeger@de.ibm.com>
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Cc: kvm <kvm@vger.kernel.org>, Carsten Otte <cotte@de.ibm.com>,
	Olaf Schnapper <os@de.ibm.com>,
	Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>,
	Izik Eidus <izike@qumranet.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>
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Christian Borntraeger wrote:
> Am Dienstag, 29. Juli 2008 schrieb Avi Kivity:
>   
>> They all start with 0 AFAIK (kvm also starts with 0, it just wants it to 
>> be a special slot).
>>     
>
> Now my brain hurts....
> Ok, so I read this as: ppc, ia64 and s390 can start with slot 0 and it is not a special slot.
> On x86 slot 0 is special, if
> * KVM_CAP_SET_TSS_ADDR is not available
> or
> * The ioctl VM_CAP_SET_TSS_ADDR returns <=0
>
>   

I think this is right.  Izik can you confirm?

> +#if defined(__x86_64__) || defined(__i386__)
> +#if defined(KVM_CAP_SET_TSS_ADDR)
> +	if (ioctl(kvm->fd, KVM_CHECK_EXTENSION, KVM_CAP_SET_TSS_ADDR) > 0)
>   

Should be <= here?

> +		i++;
> +#else
> +	i++;
> +#endif
> +#endif
>   

Suggest a helper, kvm_supports_set_tss_addr(), to reduce further 
braindamage.

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