From 577bd3ef6eed18ea3c866b2f25b14aa5e139b41f Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bj=C3=B8rn=20Mork?= Date: Wed, 9 May 2012 13:53:22 +0200 Subject: [PATCH] USB: cdc-wdm: cannot use dev_printk when device is gone MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit commit 6b0b79d38806481c1c8fffa7c5842f3c83679a42 upstream. We cannot dereference a removed USB interface for dev_printk. Use pr_debug instead where necessary. Flush errors are expected if device is unplugged and are therefore best ingored at this point. Move the kill_urbs() call in wdm_release with dev_dbg() for the non disconnect, as we know it has already been called if WDM_DISCONNECTING is set. This does not actually fix anything, but keeps the code more consistent. Cc: Oliver Neukum Signed-off-by: Bjørn Mork Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-wdm.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 1fb3d31..c184b37 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -530,7 +530,9 @@ static int wdm_flush(struct file *file, fl_owner_t id) struct wdm_device *desc = file->private_data; wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags)); - if (desc->werr < 0) + + /* cannot dereference desc->intf if WDM_DISCONNECTING */ + if (desc->werr < 0 && !test_bit(WDM_DISCONNECTING, &desc->flags)) dev_err(&desc->intf->dev, "Error in flush path: %d\n", desc->werr); @@ -621,12 +623,15 @@ static int wdm_release(struct inode *inode, struct file *file) mutex_unlock(&desc->wlock); if (!desc->count) { - dev_dbg(&desc->intf->dev, "wdm_release: cleanup"); - kill_urbs(desc); - if (!test_bit(WDM_DISCONNECTING, &desc->flags)) + if (!test_bit(WDM_DISCONNECTING, &desc->flags)) { + dev_dbg(&desc->intf->dev, "wdm_release: cleanup"); + kill_urbs(desc); desc->manage_power(desc->intf, 0); - else + } else { + /* must avoid dev_printk here as desc->intf is invalid */ + pr_debug(KBUILD_MODNAME " %s: device gone - cleaning up\n", __func__); cleanup(desc); + } } mutex_unlock(&wdm_mutex); return 0; -- 2.7.4