Re: PROBLEM: repeated remap_file_pages on tmpfs triggers bug on process exit

[Kirill A. Shutemov]

Konstantin Khlebnikov wrote:
> It seems boundng logic in do_fault_around is wrong:
> 
> start_addr = max(address & fault_around_mask(), vma->vm_start);
> off = ((address - start_addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
> pte -= off;
> pgoff -= off;
> 
> Ok, off  <= 511, but it might be bigger than pte offset in pte table.

I don't see how it possible: fault_around_mask() cannot be more than 0x1ff000
(x86-64, fault_around_bytes == 2M). It means start_addr will be aligned to 2M
boundary in this case which is start of the page table pte belong to.

Do I miss something?

-- 
 Kirill A. Shutemov
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