| Message ID | 20180904112219.89287-3-heikki.krogerus@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | usb: typec: A few more improvements for Intel CHT | expand |
HI, On 04-09-18 13:22, Heikki Krogerus wrote: > This fixes potential "BUG: unable to handle kernel paging > request at ..." from happening. > > Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches") > Cc: <stable@vger.kernel.org> > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > drivers/usb/common/roles.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/common/roles.c b/drivers/usb/common/roles.c > index 15cc76e22123..3d8a776e55ee 100644 > --- a/drivers/usb/common/roles.c > +++ b/drivers/usb/common/roles.c > @@ -109,8 +109,15 @@ static void *usb_role_switch_match(struct device_connection *con, int ep, > */ > struct usb_role_switch *usb_role_switch_get(struct device *dev) > { > - return device_connection_find_match(dev, "usb-role-switch", NULL, > - usb_role_switch_match); > + struct usb_role_switch *sw; > + > + sw = device_connection_find_match(dev, "usb-role-switch", NULL, > + usb_role_switch_match); > + > + if (!IS_ERR(sw)) > + WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); While testing I found a bug, so sorry but this is going to need a v4, device_connection_find_match() may return NULL here, so this needs to be if (!IS_ERR_OR_NULL(sw)) to avoid an oops. Note I'm also seeing some other issues which I need to debug I will do so tomorrow morning so you may want to wait a bit with v4. Regards, Hans > + > + return sw; > } > EXPORT_SYMBOL_GPL(usb_role_switch_get); > > @@ -122,8 +129,10 @@ EXPORT_SYMBOL_GPL(usb_role_switch_get); > */ > void usb_role_switch_put(struct usb_role_switch *sw) > { > - if (!IS_ERR_OR_NULL(sw)) > + if (!IS_ERR_OR_NULL(sw)) { > put_device(&sw->dev); > + module_put(sw->dev.parent->driver->owner); > + } > } > EXPORT_SYMBOL_GPL(usb_role_switch_put); > >
On Thu, Sep 06, 2018 at 10:59:34PM +0200, Hans de Goede wrote: > HI, > > On 04-09-18 13:22, Heikki Krogerus wrote: > > This fixes potential "BUG: unable to handle kernel paging > > request at ..." from happening. > > > > Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches") > > Cc: <stable@vger.kernel.org> > > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > > --- > > drivers/usb/common/roles.c | 15 ++++++++++++--- > > 1 file changed, 12 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/usb/common/roles.c b/drivers/usb/common/roles.c > > index 15cc76e22123..3d8a776e55ee 100644 > > --- a/drivers/usb/common/roles.c > > +++ b/drivers/usb/common/roles.c > > @@ -109,8 +109,15 @@ static void *usb_role_switch_match(struct device_connection *con, int ep, > > */ > > struct usb_role_switch *usb_role_switch_get(struct device *dev) > > { > > - return device_connection_find_match(dev, "usb-role-switch", NULL, > > - usb_role_switch_match); > > + struct usb_role_switch *sw; > > + > > + sw = device_connection_find_match(dev, "usb-role-switch", NULL, > > + usb_role_switch_match); > > + > > + if (!IS_ERR(sw)) > > + WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); > > While testing I found a bug, so sorry but this is going to need a v4, > device_connection_find_match() may return NULL here, so this needs > to be if (!IS_ERR_OR_NULL(sw)) to avoid an oops. > > Note I'm also seeing some other issues which I need to debug I will > do so tomorrow morning so you may want to wait a bit with v4. Np. Take your time. And thanks for testing these. Cheers,
diff --git a/drivers/usb/common/roles.c b/drivers/usb/common/roles.c index 15cc76e22123..3d8a776e55ee 100644 --- a/drivers/usb/common/roles.c +++ b/drivers/usb/common/roles.c @@ -109,8 +109,15 @@ static void *usb_role_switch_match(struct device_connection *con, int ep, */ struct usb_role_switch *usb_role_switch_get(struct device *dev) { - return device_connection_find_match(dev, "usb-role-switch", NULL, - usb_role_switch_match); + struct usb_role_switch *sw; + + sw = device_connection_find_match(dev, "usb-role-switch", NULL, + usb_role_switch_match); + + if (!IS_ERR(sw)) + WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); + + return sw; } EXPORT_SYMBOL_GPL(usb_role_switch_get); @@ -122,8 +129,10 @@ EXPORT_SYMBOL_GPL(usb_role_switch_get); */ void usb_role_switch_put(struct usb_role_switch *sw) { - if (!IS_ERR_OR_NULL(sw)) + if (!IS_ERR_OR_NULL(sw)) { put_device(&sw->dev); + module_put(sw->dev.parent->driver->owner); + } } EXPORT_SYMBOL_GPL(usb_role_switch_put);
This fixes potential "BUG: unable to handle kernel paging request at ..." from happening. Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches") Cc: <stable@vger.kernel.org> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> --- drivers/usb/common/roles.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)