4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Burton <paul.burton@xxxxxxxxxx> commit f4281bba818105c7c91799abe40bc05c0dbdaa25 upstream. The following patch will expose __update_cache to highmem pages. Handle them by mapping them in for the duration of the cache maintenance, just like in __flush_dcache_page. The code for that isn't shared because we need the page address in __update_cache so sharing became messy. Given that the entirity is an extra 5 lines, just duplicate it. Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx> Cc: Lars Persson <lars.persson@xxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Jerome Marchand <jmarchan@xxxxxxxxxx> Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Patchwork: https://patchwork.linux-mips.org/patch/12721/ Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/mm/cache.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/arch/mips/mm/cache.c +++ b/arch/mips/mm/cache.c @@ -143,9 +143,17 @@ void __update_cache(struct vm_area_struc return; page = pfn_to_page(pfn); if (page_mapping(page) && Page_dcache_dirty(page)) { - addr = (unsigned long) page_address(page); + if (PageHighMem(page)) + addr = (unsigned long)kmap_atomic(page); + else + addr = (unsigned long)page_address(page); + if (exec || pages_do_alias(addr, address & PAGE_MASK)) flush_data_cache_page(addr); + + if (PageHighMem(page)) + __kunmap_atomic((void *)addr); + ClearPageDcacheDirty(page); } }