On Tue, Jul 13, 2021 at 06:31:23PM -0700, Andrew Morton wrote: > On Tue, 13 Jul 2021 07:52:30 +0200 Christoph Hellwig <hch@xxxxxx> wrote: > > > memcpy_to_page and memzero_page can write to arbitrary pages, which could > > be in the page cache or in high memory, so call flush_kernel_dcache_pages > > to flush the dcache. > > I assume this presently is not known to cause any problems, but that > some problems might be discovered in the future? In which case, > should we cc:stable? This is a problem when using these helpers on dcache challeneged architectures. Right now there are just a few users, chances are no one used the PC floppy drіver, the aha1542 driver for an ISA SCSI HBA, and a few advanced and optional btrfs and ext4 features on those platforms yet since the conversion. So yes, stable would be good.
