Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756550AbaDXL7O (ORCPT ); Thu, 24 Apr 2014 07:59:14 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:46300 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753360AbaDXIwU (ORCPT ); Thu, 24 Apr 2014 04:52:20 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Sebastian Ott , Martin Schwidefsky , Luis Henriques Subject: [PATCH 3.11 017/182] s390/cio: fix driver callback initialization for ccw consoles Date: Thu, 24 Apr 2014 09:49:02 +0100 Message-Id: <1398329507-5911-18-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1398329507-5911-1-git-send-email-luis.henriques@canonical.com> References: <1398329507-5911-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.9 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Ott commit 2253e8d79237c69086ded391e6767afe16972527 upstream. ccw consoles are in use before they can be properly registered with the driver core. For devices which are in use by a device driver we rely on the ccw_device's pointer to the driver callbacks to be valid. For ccw consoles this pointer is NULL until they are registered later during boot and we dereferenced this pointer. This worked by chance on 64 bit builds (cdev->drv was NULL but the optional callback cdev->drv->path_event was also NULL by coincidence) and was unnoticed until we received reports about boot failures on 31 bit systems. Fix it by initializing the driver pointer for ccw consoles. Reported-by: Mike Frysinger Reported-by: Heiko Carstens Reviewed-by: Peter Oberparleiter Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky Signed-off-by: Luis Henriques --- arch/s390/include/asm/ccwdev.h | 2 +- drivers/s390/char/con3215.c | 2 +- drivers/s390/char/con3270.c | 6 +----- drivers/s390/char/raw3270.c | 10 +++++++++- drivers/s390/char/raw3270.h | 2 +- drivers/s390/cio/device.c | 3 ++- 6 files changed, 15 insertions(+), 10 deletions(-) diff --git a/arch/s390/include/asm/ccwdev.h b/arch/s390/include/asm/ccwdev.h index f201af8..31b5ca8 100644 --- a/arch/s390/include/asm/ccwdev.h +++ b/arch/s390/include/asm/ccwdev.h @@ -219,7 +219,7 @@ extern void ccw_device_get_id(struct ccw_device *, struct ccw_dev_id *); #define to_ccwdev(n) container_of(n, struct ccw_device, dev) #define to_ccwdrv(n) container_of(n, struct ccw_driver, driver) -extern struct ccw_device *ccw_device_probe_console(void); +extern struct ccw_device *ccw_device_probe_console(struct ccw_driver *); extern void ccw_device_wait_idle(struct ccw_device *); extern int ccw_device_force_console(struct ccw_device *); diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c index eb5d227..bb86494 100644 --- a/drivers/s390/char/con3215.c +++ b/drivers/s390/char/con3215.c @@ -922,7 +922,7 @@ static int __init con3215_init(void) raw3215_freelist = req; } - cdev = ccw_device_probe_console(); + cdev = ccw_device_probe_console(&raw3215_ccw_driver); if (IS_ERR(cdev)) return -ENODEV; diff --git a/drivers/s390/char/con3270.c b/drivers/s390/char/con3270.c index 699fd3e..bb6b0df 100644 --- a/drivers/s390/char/con3270.c +++ b/drivers/s390/char/con3270.c @@ -576,7 +576,6 @@ static struct console con3270 = { static int __init con3270_init(void) { - struct ccw_device *cdev; struct raw3270 *rp; void *cbuf; int i; @@ -591,10 +590,7 @@ con3270_init(void) cpcmd("TERM AUTOCR OFF", NULL, 0, NULL); } - cdev = ccw_device_probe_console(); - if (IS_ERR(cdev)) - return -ENODEV; - rp = raw3270_setup_console(cdev); + rp = raw3270_setup_console(); if (IS_ERR(rp)) return PTR_ERR(rp); diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c index 24a08e8..651d1f5 100644 --- a/drivers/s390/char/raw3270.c +++ b/drivers/s390/char/raw3270.c @@ -776,16 +776,24 @@ raw3270_setup_device(struct ccw_device *cdev, struct raw3270 *rp, char *ascebc) } #ifdef CONFIG_TN3270_CONSOLE +/* Tentative definition - see below for actual definition. */ +static struct ccw_driver raw3270_ccw_driver; + /* * Setup 3270 device configured as console. */ -struct raw3270 __init *raw3270_setup_console(struct ccw_device *cdev) +struct raw3270 __init *raw3270_setup_console(void) { + struct ccw_device *cdev; unsigned long flags; struct raw3270 *rp; char *ascebc; int rc; + cdev = ccw_device_probe_console(&raw3270_ccw_driver); + if (IS_ERR(cdev)) + return ERR_CAST(cdev); + rp = kzalloc(sizeof(struct raw3270), GFP_KERNEL | GFP_DMA); ascebc = kzalloc(256, GFP_KERNEL); rc = raw3270_setup_device(cdev, rp, ascebc); diff --git a/drivers/s390/char/raw3270.h b/drivers/s390/char/raw3270.h index 7b73ff8..359276a 100644 --- a/drivers/s390/char/raw3270.h +++ b/drivers/s390/char/raw3270.h @@ -190,7 +190,7 @@ raw3270_put_view(struct raw3270_view *view) wake_up(&raw3270_wait_queue); } -struct raw3270 *raw3270_setup_console(struct ccw_device *cdev); +struct raw3270 *raw3270_setup_console(void); void raw3270_wait_cons_dev(struct raw3270 *); /* Notifier for device addition/removal */ diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c index 1ab5f6c..8d04a9a 100644 --- a/drivers/s390/cio/device.c +++ b/drivers/s390/cio/device.c @@ -1610,7 +1610,7 @@ out_unlock: return rc; } -struct ccw_device *ccw_device_probe_console(void) +struct ccw_device *ccw_device_probe_console(struct ccw_driver *drv) { struct io_subchannel_private *io_priv; struct ccw_device *cdev; @@ -1632,6 +1632,7 @@ struct ccw_device *ccw_device_probe_console(void) kfree(io_priv); return cdev; } + cdev->drv = drv; set_io_private(sch, io_priv); ret = ccw_device_console_enable(cdev, sch); if (ret) { -- 1.9.1 -- 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/