Re: [PATCH v10 0/4] mm/vmalloc: free unused pages on vrealloc() shrink

[Shivam Kalra <shivamkalra98@zohomail.in>]

On 16/04/26 00:14, Uladzislau Rezki wrote:
> Yep, the problem reported by Sashiko regarding area->size and vread_iter()
> is correct. V10 does not address this.
> 
> I am not sure that reducing vma size is a good approach here. It is
> widely used and we might end up with fixing even more corner cases.
> 
> vread_iter() and vm-size calculation there should be fixed.
> 
> --
> Uladzislau Rezki
Proposed Change for v11:

long vread_iter(struct iov_iter *iter, const char *addr, size_t count)
{
	struct vmap_node *vn;
	struct vmap_area *va;
	struct vm_struct *vm;
	char *vaddr;
<snip>
  		vaddr = (char *) va->va_start;
  		size = vm ? get_vm_area_size(vm) : va_size(va);
		
		if (vm && vm->nr_pages)
	            size = min(size, (size_t)vm->nr_pages << PAGE_SHIFT);

<snip>