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Date:   Tue, 6 Jul 2021 14:16:06 -0700
From:   Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
To:     Eduardo Habkost <ehabkost@redhat.com>
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Subject: Re: [PATCH 4/4] x86/tsx: Add cmdline tsx=fake to not clear CPUID
 bits RTM and HLE
Message-ID: <20210706211606.ezme3xvwztagbjqy@gupta-dev2.localdomain>
References: <cover.2d906c322f72ec1420955136ebaa7a4c5073917c.1623272033.git-series.pawan.kumar.gupta@linux.intel.com>
 <de6b97a567e273adff1f5268998692bad548aa10.1623272033.git-series.pawan.kumar.gupta@linux.intel.com>
 <20210706195233.h6w4cm73oktfqpgz@habkost.net>
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On 06.07.2021 15:52, Eduardo Habkost wrote:
>On Wed, Jun 09, 2021 at 02:14:39PM -0700, Pawan Gupta wrote:
>> On CPUs that deprecated TSX, clearing the enumeration bits CPUID.RTM and
>> CPUID.HLE may not be desirable in some corner cases. Like a saved guest
>> would refuse to resume if it was saved before the microcode update
>> that deprecated TSX.
>
>Why is a global option necessary to allow those guests to be
>resumed?  Why can't KVM_GET_SUPPORTED_CPUID always return the HLE
>and RTM bits as supported when the host CPU has them?

Yes, the global option is unnecessary and this patch was dropped in v2.

Thanks,
Pawan