Re: [PATCH v3 3/5] mm: x86: Invoke hypercall when page encryption status is changed

[Ashish Kalra <ashish.kalra@amd.com>]

Hello Boris, Paolo,

On Thu, Jun 10, 2021 at 08:30:52PM +0200, Borislav Petkov wrote:
> On Tue, Jun 08, 2021 at 06:06:26PM +0000, Ashish Kalra wrote:
> > +void notify_range_enc_status_changed(unsigned long vaddr, int npages,
> > +				    bool enc)
> 
> You don't need to break this line.
> 
> > @@ -285,12 +333,13 @@ static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc)
> >  static int __init early_set_memory_enc_dec(unsigned long vaddr,
> >  					   unsigned long size, bool enc)
> >  {
> > -	unsigned long vaddr_end, vaddr_next;
> > +	unsigned long vaddr_end, vaddr_next, start;
> >  	unsigned long psize, pmask;
> >  	int split_page_size_mask;
> >  	int level, ret;
> >  	pte_t *kpte;
> >  
> > +	start = vaddr;
> >  	vaddr_next = vaddr;
> >  	vaddr_end = vaddr + size;
> >  
> > @@ -345,6 +394,8 @@ static int __init early_set_memory_enc_dec(unsigned long vaddr,
> >  
> >  	ret = 0;
> >  
> > +	notify_range_enc_status_changed(start, PAGE_ALIGN(size) >> PAGE_SHIFT,
> > +					enc);
> 
> Ditto.
> 
> >  out:
> >  	__flush_tlb_all();
> >  	return ret;
> > diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
> > index 156cd235659f..9729cb0d99e3 100644
> > --- a/arch/x86/mm/pat/set_memory.c
> > +++ b/arch/x86/mm/pat/set_memory.c
> > @@ -2020,6 +2020,13 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
> >  	 */
> >  	cpa_flush(&cpa, 0);
> >  
> > +	/*
> > +	 * Notify hypervisor that a given memory range is mapped encrypted
> > +	 * or decrypted. The hypervisor will use this information during the
> > +	 * VM migration.
> > +	 */
> 
> Simplify that comment:
> 
>         /*
>          * Notify the hypervisor about the encryption status change of the memory
> 	 * range. It will use this information during the VM migration.
>          */
> 
> 
> With those nitpicks fixed:
> 
> Reviewed-by: Borislav Petkov <bp@suse.de>
> 
> Paulo, if you want me to take this, lemme know, but I think it'll
> conflict with patch 5 so perhaps it all should go together through the
> kvm tree...
> 

Will these patches be merged into 5.14 ?

I have posted another version (v5) for patch 5 after more review comments
from Boris, so please pull in all these patches together. 

Thanks,
Ashish

> Thx.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
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