Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270980AbUJUVYP (ORCPT ); Thu, 21 Oct 2004 17:24:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270971AbUJUVWp (ORCPT ); Thu, 21 Oct 2004 17:22:45 -0400 Received: from e32.co.us.ibm.com ([32.97.110.130]:45458 "EHLO e32.co.us.ibm.com") by vger.kernel.org with ESMTP id S270969AbUJUVPs (ORCPT ); Thu, 21 Oct 2004 17:15:48 -0400 Subject: [PATCH] zap_pte_range should not mark non-uptodate pages dirty From: Dave Kleikamp To: Andrew Morton Cc: Andrea Arcangeli , linux-kernel , linux-mm@kvack.org Content-Type: text/plain Message-Id: <1098393346.7157.112.camel@localhost> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Thu, 21 Oct 2004 16:15:46 -0500 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1436 Lines: 35 zap_pte_range should not mark non-uptodate pages dirty Doing O_DIRECT writes to an mmapped file caused pages in the page cache to be marked dirty but not uptodate. This led to a bug in mpage_writepage. Signed-off-by: Dave Kleikamp Signed-off-by: Andrea Arcangeli diff -urp linux-2.6.9/mm/memory.c linux/mm/memory.c --- linux-2.6.9/mm/memory.c 2004-10-21 10:49:26.598031488 -0500 +++ linux/mm/memory.c 2004-10-21 16:01:44.902376232 -0500 @@ -414,7 +414,15 @@ static void zap_pte_range(struct mmu_gat && linear_page_index(details->nonlinear_vma, address+offset) != page->index) set_pte(ptep, pgoff_to_pte(page->index)); - if (pte_dirty(pte)) + /* + * PG_uptodate can be cleared by + * invalidate_inode_pages2, so we must not try to write + * not uptodate pages. Otherwise we risk invalidating + * underlying O_DIRECT writes, and secondly because + * pdflush would BUG(). Coherency of mmaps against + * O_DIRECT still cannot be guaranteed though. + */ + if (pte_dirty(pte) && PageUptodate(page)) set_page_dirty(page); if (pte_young(pte) && !PageAnon(page)) mark_page_accessed(page); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/