From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>
Subject: Re: [PATCH 08/20] target-ppc: Add hooks for handling tcg and kvm
 limitations
Date: Mon, 16 Apr 2012 12:19:46 +0200
Message-ID: <4F8BF242.2080807@suse.de>
References: <1334515144-26485-1-git-send-email-afaerber@suse.de> <1334515144-26485-9-git-send-email-afaerber@suse.de> <4F8BF0D0.2090109@redhat.com>
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Cc: qemu-devel@nongnu.org, qemu-ppc@nongnu.org, blauwirbel@gmail.com,
	agraf@suse.de, David Gibson <david@gibson.dropbear.id.au>,
	"Marcelo Tosatti (supporter:Overall)" <mtosatti@redhat.com>,
	open@suse.de, "list@suse.de:Overall" <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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Am 16.04.2012 12:13, schrieb Avi Kivity:
> On 04/15/2012 09:38 PM, Andreas F=C3=A4rber wrote:
>> From: David Gibson <david@gibson.dropbear.id.au>
>>
>> On target-ppc, our table of CPU types and features encodes the featu=
res as
>> found on the hardware, regardless of whether these features are actu=
ally
>> usable under TCG or KVM.  We already have cases where the informatio=
n from
>> the cpu table must be fixed up to account for limitations in the emu=
lation
>> method we're using.  e.g. TCG does not support the DFP and VSX instr=
uctions
>> and KVM needs different numbering of the CPUs in order to tell it th=
e
>> correct thread to core mappings.
>>
>> This patch cleans up these hacks to handle emulation limitations by
>> consolidating them into a pair of functions specifically for the pur=
pose.
>>
>>      env->check_pow =3D def->check_pow;
>> +
>> +    if (kvm_enabled()) {
>> +        if (kvmppc_fixup_cpu(env) !=3D 0) {
>> +            fprintf(stderr, "Unable to virtualize selected CPU with=
 KVM\n");
>> +            exit(1);
>> +        }
>> +    } else {
>> +        if (ppc_fixup_cpu(env) !=3D 0) {
>> +            fprintf(stderr, "Unable to emulate selected CPU with TC=
G\n");
>> +            exit(1);
>> +        }
>> +    }
>> +
>>
>=20
> I wish we had an error like that for x86.  Right now we silently add =
and
> drop cpu features.

x86 has an ,+enforce option for that, doesn't it?

Andreas

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