| Message ID | 20230913201248.452081-6-zi.yan@sent.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Use nth_page() in place of direct struct page manipulation | expand |
On 13 Sep 2023, at 16:12, Zi Yan wrote: > From: Zi Yan <ziy@nvidia.com> > > __flush_dcache_pages() is called during hugetlb migration via > migrate_pages() -> migrate_hugetlbs() -> unmap_and_move_huge_page() > -> move_to_new_folio() -> flush_dcache_folio(). And with hugetlb and > without sparsemem vmemmap, struct page is not guaranteed to be contiguous > beyond a section. Use nth_page() instead. > > Fixes: 15fa3e8e3269 ("mips: implement the new page table range API") > Cc: <stable@vger.kernel.org> > Signed-off-by: Zi Yan <ziy@nvidia.com> > --- > arch/mips/mm/cache.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c > index 02042100e267..7f830634dbe7 100644 > --- a/arch/mips/mm/cache.c > +++ b/arch/mips/mm/cache.c > @@ -117,7 +117,7 @@ void __flush_dcache_pages(struct page *page, unsigned int nr) > * get faulted into the tlb (and thus flushed) anyways. > */ > for (i = 0; i < nr; i++) { > - addr = (unsigned long)kmap_local_page(page + i); > + addr = (unsigned long)kmap_local_page(nth_page(page, i)); > flush_data_cache_page(addr); > kunmap_local((void *)addr); > } > -- > 2.40.1 Without the fix, a wrong address might be used for data cache page flush. No bug is reported. The fix comes from code inspection. -- Best Regards, Yan, Zi
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c index 02042100e267..7f830634dbe7 100644 --- a/arch/mips/mm/cache.c +++ b/arch/mips/mm/cache.c @@ -117,7 +117,7 @@ void __flush_dcache_pages(struct page *page, unsigned int nr) * get faulted into the tlb (and thus flushed) anyways. */ for (i = 0; i < nr; i++) { - addr = (unsigned long)kmap_local_page(page + i); + addr = (unsigned long)kmap_local_page(nth_page(page, i)); flush_data_cache_page(addr); kunmap_local((void *)addr); }