Re: [PATCH V2 4/13] KVM/MMU: Flush tlb directly in the kvm_handle_hva_range()

From: Tianyu Lan
Date: Thu Sep 20 2018 - 10:30:23 EST


On 9/20/2018 12:08 AM, Michael Kelley (EOSG) wrote:
> From: Tianyu Lan Sent: Monday, September 17, 2018 8:19 PM
>> +
>> + if (ret && kvm_available_flush_tlb_with_range()) {
>> + kvm_flush_remote_tlbs_with_address(kvm,
>> + gfn_start,
>> + gfn_end - gfn_start);
>
> Does the above need to be gfn_end - gfn_start + 1?

The flush range depends on the input parameter frame start and frame end
of for_each_slot_rmap_range().

for_each_slot_rmap_range(memslot, PT_PAGE_TABLE_LEVEL,
PT_MAX_HUGEPAGE_LEVEL,
gfn_start, gfn_end - 1,
&iterator)
ret |= handler(kvm, iterator.rmap, memslot,
iterator.gfn, iterator.level, data);


The start is "gfn_start" and the end is "gfn_end - 1". The flush size is
(gfn_end - 1) - gfn_start + 1 = gfn_end - gfn_start.

>
>> + ret = 0;
>> + }
>
> Michael
>