Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <c752d17e-23fd-4452-e1d8-6c82748b6c8a@intel.com>
Date:   Mon, 28 Nov 2022 05:18:12 -0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.2.2
Subject: Re: [PATCH v7 14/20] x86/virt/tdx: Set up reserved areas for all
 TDMRs
Content-Language: en-US
To:     "Huang, Kai" <kai.huang@intel.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Cc:     "Luck, Tony" <tony.luck@intel.com>,
        "bagasdotme@gmail.com" <bagasdotme@gmail.com>,
        "ak@linux.intel.com" <ak@linux.intel.com>,
        "Wysocki, Rafael J" <rafael.j.wysocki@intel.com>,
        "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
        "Christopherson,, Sean" <seanjc@google.com>,
        "Chatre, Reinette" <reinette.chatre@intel.com>,
        "pbonzini@redhat.com" <pbonzini@redhat.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "Yamahata, Isaku" <isaku.yamahata@intel.com>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "Shahar, Sagi" <sagis@google.com>,
        "imammedo@redhat.com" <imammedo@redhat.com>,
        "Gao, Chao" <chao.gao@intel.com>,
        "Brown, Len" <len.brown@intel.com>,
        "sathyanarayanan.kuppuswamy@linux.intel.com" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        "Huang, Ying" <ying.huang@intel.com>,
        "Williams, Dan J" <dan.j.williams@intel.com>
References: <cover.1668988357.git.kai.huang@intel.com>
 <5a5644e691134dc72c5e3fb0fc22fa40d4aa0b34.1668988357.git.kai.huang@intel.com>
 <5526fedd-fa54-0ad2-f356-94b167e6e290@intel.com>
 <0ebf26d1ee540b4e082b65c51cabe3327f6d51ac.camel@intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <0ebf26d1ee540b4e082b65c51cabe3327f6d51ac.camel@intel.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 11/28/22 01:14, Huang, Kai wrote:
> On Wed, 2022-11-23 at 15:39 -0800, Dave Hansen wrote:
...
>> /*
>>  * Go through tdx_memlist to find holes between memory areas.  If any of
>>  * those holes fall within @tdmr, set up a TDMR reserved area to cover
>>  * the hole.
>>  */
>> static int tdmr_populate_rsvd_holes(struct list_head *tdx_memlist,
>> 				    struct tdmr_info *tdmr,
>> 				    int *rsvd_idx)
> 
> Thanks!
> 
> Should I also change below function 'tdmr_set_up_pamt_rsvd_areas()' to, i.e.
> tdmr_populate_rsvd_pamts()?
> 
> Actually, there are two more functions in this patch: tdmr_set_up_rsvd_areas()
> and tdmrs_set_up_rsvd_areas_all().  Should I also change them to
> tdmr_populate_rsvd_areas() and tdmrs_populate_rsvd_areas_all()? 

I don't know.  I'll look at the naming again once I see it all together.

>> but I also get the feeling that 'prev_end' is a crummy variable name.  I
>> don't have any better suggestions at the moment.
>>
>>> +	list_for_each_entry(tmb, &tdx_memlist, list) {
>>> +		u64 start, end;
>>> +
>>> +		start = tmb->start_pfn << PAGE_SHIFT;
>>> +		end = tmb->end_pfn << PAGE_SHIFT;
>>> +
>>
>> More alignment opportunities:
>>
>> 		start = tmb->start_pfn << PAGE_SHIFT;
>> 		end   = tmb->end_pfn   << PAGE_SHIFT;
> 
> Should I use PFN_PHYS()?  Then looks we don't need this alignment.

Sure.