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To:     <like.xu@linux.intel.com>
References: <20210329054137.120994-2-like.xu@linux.intel.com>
Subject: Re: [PATCH v4 01/16] perf/x86/intel: Add x86_pmu.pebs_vmx for Ice
 Lake Servers
CC:     <andi@firstfloor.org>, "Fangyi (Eric)" <eric.fangyi@huawei.com>,
        Xiexiangyou <xiexiangyou@huawei.com>,
        <kan.liang@linux.intel.com>, <kvm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <wei.w.wang@intel.com>,
        <x86@kernel.org>
From:   "Liuxiangdong (Aven, Cloud Infrastructure Service Product Dept.)" 
        <liuxiangdong5@huawei.com>
Message-ID: <606BD46F.7050903@huawei.com>
Date:   Tue, 6 Apr 2021 11:24:31 +0800
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Hi，like.
Some questions about this new pebs patches set：
https://lore.kernel.org/kvm/20210329054137.120994-2-like.xu@linux.intel.com/

The new hardware facility supporting guest PEBS is only available
on Intel Ice Lake Server platforms for now.


AFAIK， Icelake supports adaptive PEBS and extended PEBS which Skylake 
doesn't.
But we can still use IA32_PEBS_ENABLE MSR to indicate general-purpose 
counter in Skylake.
Is there anything else that only Icelake supports in this patches set?


Besides, we have tried this patches set in Icelake.  We can use pebs(eg: 
"perf record -e cycles:pp")
when guest is kernel-5.11, but can't when kernel-4.18.  Is there a 
minimum guest kernel version requirement?


Thanks,
Xiangdong Liu