Re: [PATCHv4 3/3] x86/tdx: Handle load_unaligned_zeropad() page-cross to a shared page

[Dave Hansen]

On 6/15/22 15:52, Kirill A. Shutemov wrote:
>> +	vaddr = (unsigned long)insn_get_addr_ref(&insn, regs);
>> +	if (vaddr / PAGE_SIZE != (vaddr + size) / PAGE_SIZE)
> Oops. I just realized it has off-by-one. It supposed to be:
> 
> 	if (vaddr / PAGE_SIZE != (vaddr + size - 1) / PAGE_SIZE)

That was bugging me.  Glad you caught this.

Wouldn't this be more obviously correct?

	if (ALIGN_DOWN(vaddr,        PAGE_SIZE) !=
	    ALIGN_DOWN(vaddr + size, PAGE_SIZE))
		...

I don't think we have a PAGE_ALIGN_DOWN().