On Wed, Feb 07, 2018 at 02:54:30PM +0800, Wei Wang wrote: > In some usages, e.g. virtio-balloon, a kernel module needs to know if > page poisoning is in use. This patch exposes the page_poisoning_enabled > function to kernel modules. > > Signed-off-by: Wei Wang <wei.w.wang@xxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> > --- > mm/page_poison.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/mm/page_poison.c b/mm/page_poison.c > index e83fd44..c08d02a 100644 > --- a/mm/page_poison.c > +++ b/mm/page_poison.c > @@ -30,6 +30,11 @@ bool page_poisoning_enabled(void) > debug_pagealloc_enabled())); > } > > +/** > + * page_poisoning_enabled - check if page poisoning is enabled > + * > + * Return true if page poisoning is enabled, or false if not. > + */ > static void poison_page(struct page *page) > { > void *addr = kmap_atomic(page); > @@ -37,6 +42,7 @@ static void poison_page(struct page *page) > memset(addr, PAGE_POISON, PAGE_SIZE); > kunmap_atomic(addr); > } > +EXPORT_SYMBOL_GPL(page_poisoning_enabled); > > static void poison_pages(struct page *page, int n) > { Looks like both the comment and the export are in the wrong place. I'm a bit concerned that callers also in fact poke at the PAGE_POISON - exporting that seems to be more of an accident as it's only used without page_poisoning.c - it might be better to have page_poisoning_enabled get u8 * and set it. > -- > 2.7.4 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization