Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755229Ab0GASKx (ORCPT ); Thu, 1 Jul 2010 14:10:53 -0400 Received: from kroah.org ([198.145.64.141]:60049 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754840Ab0GASKu (ORCPT ); Thu, 1 Jul 2010 14:10:50 -0400 X-Mailbox-Line: From gregkh@clark.site Thu Jul 1 10:28:57 2010 Message-Id: <20100701172857.301476632@clark.site> User-Agent: quilt/0.48-10.1 Date: Thu, 01 Jul 2010 10:26:59 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jeff Moyer , Rik van Riel , Larry Woodman Subject: [10/23] do_generic_file_read: clear page errors when issuing a fresh read of the page In-Reply-To: <20100701175134.GA2098@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1681 Lines: 53 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Jeff Moyer commit 91803b499cca2fe558abad709ce83dc896b80950 upstream. I/O errors can happen due to temporary failures, like multipath errors or losing network contact with the iSCSI server. Because of that, the VM will retry readpage on the page. However, do_generic_file_read does not clear PG_error. This causes the system to be unable to actually use the data in the page cache page, even if the subsequent readpage completes successfully! The function filemap_fault has had a ClearPageError before readpage forever. This patch simply adds the same to do_generic_file_read. Signed-off-by: Jeff Moyer Signed-off-by: Rik van Riel Acked-by: Larry Woodman Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/filemap.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1118,6 +1118,12 @@ page_not_up_to_date_locked: } readpage: + /* + * A previous I/O error may have been due to temporary + * failures, eg. multipath errors. + * PG_error will be set again if readpage fails. + */ + ClearPageError(page); /* Start the actual read. The read will unlock the page. */ error = mapping->a_ops->readpage(filp, 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/