Re: [PATCH] Support HIGHMEM pages in vmap_pages_range_noflush()

[William Kucharski <william.kucharski@oracle.com>]

Looks good and IMHO it's more self-documenting.

Reviewed-by: <william.kucharski@oracle.com>

> On Aug 18, 2022, at 3:07 PM, Matthew Wilcox <willy@infradead.org> wrote:
> 
> If the pages being mapped are in HIGHMEM, page_address() returns NULL.
> This probably wasn't noticed before because there aren't currently
> any architectures with HAVE_ARCH_HUGE_VMALLOC and HIGHMEM, but it's
> simpler to call page_to_phys() and futureproofs us against such
> configurations existing.
> 
> Fixes: 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings")
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index dd6cdb201195..bea9b0c37295 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -590,7 +590,7 @@ int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
> int err;
> 
> err = vmap_range_noflush(addr, addr + (1UL << page_shift),
> - __pa(page_address(pages[i])), prot,
> + page_to_phys(pages[i]), prot,
> page_shift);
> if (err)
> return err;
>