From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: [PATCH] hugetlb: call arch_prepare_hugepage() for surplus pages Date: Wed, 6 Aug 2008 01:36:16 +1000 References: <1217950147.5032.15.camel@localhost.localdomain> In-Reply-To: <1217950147.5032.15.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200808060136.17277.nickpiggin@yahoo.com.au> Sender: owner-linux-mm@kvack.org Return-Path: To: Gerald Schaefer Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-s390@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, Nishanth Aravamudan , Adam Litke List-ID: On Wednesday 06 August 2008 01:29, Gerald Schaefer wrote: > From: Gerald Schaefer > > The s390 software large page emulation implements shared page tables > by using page->index of the first tail page from a compound large page > to store page table information. This is set up in arch_prepare_hugepage(), > which is called from alloc_fresh_huge_page_node(). > > A similar call to arch_prepare_hugepage() is missing for surplus large > pages that are allocated in alloc_buddy_huge_page(), which breaks the > software emulation mode for (surplus) large pages on s390. This patch > adds the missing call to arch_prepare_hugepage(). It will have no effect > on other architectures where arch_prepare_hugepage() is a nop. > > Acked-by: Martin Schwidefsky > Signed-off-by: Gerald Schaefer > --- > > mm/hugetlb.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > Index: linux/mm/hugetlb.c > =================================================================== > --- linux.orig/mm/hugetlb.c > +++ linux/mm/hugetlb.c > @@ -565,7 +565,7 @@ static struct page *alloc_fresh_huge_pag > huge_page_order(h)); > if (page) { > if (arch_prepare_hugepage(page)) { > - __free_pages(page, HUGETLB_PAGE_ORDER); > + __free_pages(page, huge_page_order(h)); > return NULL; > } > prep_new_huge_page(h, page, nid); This looks like a seperate bugfix? > @@ -665,6 +665,11 @@ static struct page *alloc_buddy_huge_pag > __GFP_REPEAT|__GFP_NOWARN, > huge_page_order(h)); > > + if (page && arch_prepare_hugepage(page)) { > + __free_pages(page, huge_page_order(h)); > + return NULL; > + } > + > spin_lock(&hugetlb_lock); > if (page) { > /* Acked-by: Nick Piggin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org