On Wed, 2014-06-18 at 15:38 +0900, Yasuaki Ishimatsu wrote: : > @@ -186,7 +186,12 @@ void sync_global_pgds(unsigned long start, unsigned long end) > const pgd_t *pgd_ref = pgd_offset_k(address); > struct page *page; > > - if (pgd_none(*pgd_ref)) > + /* > + * When it is called after memory hot remove, pgd_none() > + * returns true. In this case (removed == 1), we must clear > + * the PGD entries in the local PGD level page. > + */ > + if (pgd_none(*pgd_ref) && !removed) > continue; > > spin_lock(&pgd_lock); > @@ -199,12 +204,18 @@ void sync_global_pgds(unsigned long start, unsigned long end) > pgt_lock = &pgd_page_get_mm(page)->page_table_lock; > spin_lock(pgt_lock); > > - if (pgd_none(*pgd)) > - set_pgd(pgd, *pgd_ref); > - else > + if (!pgd_none(*pgd_ref) && !pgd_none(*pgd)) > BUG_ON(pgd_page_vaddr(*pgd) > != pgd_page_vaddr(*pgd_ref)); > > + if (removed) { Shouldn't this condition be "else if"? Thanks, -Toshi > + if (pgd_none(*pgd_ref) && !pgd_none(*pgd)) > + pgd_clear(pgd); > + } else { > + if (pgd_none(*pgd)) > + set_pgd(pgd, *pgd_ref); > + } > + > spin_unlock(pgt_lock); > } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>