Re: [BUG][PATCH -mm] bluetooth : rfcomm add get/put device in del_conn
On Dec 26, 2007 11:13 AM, Dave Young <[EMAIL PROTECTED]> wrote: > > On Tue, Dec 25, 2007 at 06:07:24PM +0800, Dave Young wrote: > > On Dec 25, 2007 6:03 PM, Dave Young <[EMAIL PROTECTED]> wrote: > > > Due to 2.6.24-rc6-mm1 kernel changes (maybe kobject or driver core), If I > > > exec: > > > > > > rfcomm connect 0 1 > > > > > > kernel will oops after connect timeout. > > > > > > hand copy some oops text: > > > > > > EIP is at driver_sysfs_remove+0x1a/0x40 > > > Call Trace: > > > show_trace_log_lvl+0x1a/0x30 > > > show_stack_log_lvl+0x9a/0xc0 > > > show_registers+0xc7/0x270 > > > die+0x129/0x240 > > > do_page_fault+0x3a1/0x670 > > > error_code+0x72/0x78 > > > __device_release_driver+0x1e/0xa0 > > > device_release_driver+0x30/0x50 > > > bus_remove_device+0x63/0x90 > > > device_del+0x55/0x190 > > > del_conn+0xb/0x10 [bluetooth] > > > run_workqueue+0xe1/0x210 > > > worker_thread+0x99/0xf0 > > > kthread+0x5c/0xa0 > > > kernel_thread_helper+0x7/0x18 > > > > > > (The remote bluetooth device is a mobile phone which is power off) > > > > > > The reason is that in bus_remobe_dev, the klist_del function will release > > > the device, so just add a get/put pair around the device_del in del_conn. > > > > > > Signed-off-by: Dave Young <[EMAIL PROTECTED]> > > > > > > --- > > > net/bluetooth/hci_sysfs.c |2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff -upr linux/net/bluetooth/hci_sysfs.c > > > linux.new/net/bluetooth/hci_sysfs.c > > > --- linux/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:09.0 > > > +0800 > > > +++ linux.new/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:51.0 > > > +0800 > > > @@ -319,7 +319,9 @@ void hci_conn_add_sysfs(struct hci_conn > > > static void del_conn(struct work_struct *work) > > > { > > > struct hci_conn *conn = container_of(work, struct hci_conn, work); > > > + get_device(&conn->dev); > > > device_del(&conn->dev); > > > + put_device(&conn->dev); > > > } > > > > > > void hci_conn_del_sysfs(struct hci_conn *conn) > > > > > > > Hi greg, > > > > BTW, Is it a possible bug of driver core or kobject ? > > > > In device_del > > if(parent) > klist_del() will drop the kref of device > > and then in bus_remove_device > klist_del() will drop it again, so the device would be released. > > then the following works will oops. > > So might my patch is a wrong fix. how about the below one: > > Signed-off-by: Dave Young <[EMAIL PROTECTED]> > > --- > drivers/base/core.c |2 ++ > 1 file changed, 2 insertions(+) > > diff -upr linux/drivers/base/core.c linux.new/drivers/base/core.c > --- linux/drivers/base/core.c 2007-12-26 11:00:49.0 +0800 > +++ linux.new/drivers/base/core.c 2007-12-26 11:01:18.0 +0800 > @@ -926,6 +926,7 @@ void device_del(struct device * dev) > struct device * parent = dev->parent; > struct class_interface *class_intf; > > + dev = get_device(dev); > if (parent) > klist_del(&dev->knode_parent); > if (MAJOR(dev->devt)) > @@ -966,6 +967,7 @@ void device_del(struct device * dev) > cleanup_device_parent(dev); > kobject_del(&dev->kobj); > put_device(parent); > + put_device(dev); > } > > /** > Hi all, The patches in this thread of me are wrong fixes, I'm sorry for this. I've found the real problem(BUG), it's in bluetooth connection code, because of workqueue delay, the device could be put before the device_del called. I will submit a new patch in a while. Regards dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [BUG][PATCH -mm] bluetooth : rfcomm add get/put device in del_conn
On Tue, Dec 25, 2007 at 06:07:24PM +0800, Dave Young wrote: > On Dec 25, 2007 6:03 PM, Dave Young <[EMAIL PROTECTED]> wrote: > > Due to 2.6.24-rc6-mm1 kernel changes (maybe kobject or driver core), If I > > exec: > > > > rfcomm connect 0 1 > > > > kernel will oops after connect timeout. > > > > hand copy some oops text: > > > > EIP is at driver_sysfs_remove+0x1a/0x40 > > Call Trace: > > show_trace_log_lvl+0x1a/0x30 > > show_stack_log_lvl+0x9a/0xc0 > > show_registers+0xc7/0x270 > > die+0x129/0x240 > > do_page_fault+0x3a1/0x670 > > error_code+0x72/0x78 > > __device_release_driver+0x1e/0xa0 > > device_release_driver+0x30/0x50 > > bus_remove_device+0x63/0x90 > > device_del+0x55/0x190 > > del_conn+0xb/0x10 [bluetooth] > > run_workqueue+0xe1/0x210 > > worker_thread+0x99/0xf0 > > kthread+0x5c/0xa0 > > kernel_thread_helper+0x7/0x18 > > > > (The remote bluetooth device is a mobile phone which is power off) > > > > The reason is that in bus_remobe_dev, the klist_del function will release > > the device, so just add a get/put pair around the device_del in del_conn. > > > > Signed-off-by: Dave Young <[EMAIL PROTECTED]> > > > > --- > > net/bluetooth/hci_sysfs.c |2 ++ > > 1 file changed, 2 insertions(+) > > > > diff -upr linux/net/bluetooth/hci_sysfs.c > > linux.new/net/bluetooth/hci_sysfs.c > > --- linux/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:09.0 +0800 > > +++ linux.new/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:51.0 +0800 > > @@ -319,7 +319,9 @@ void hci_conn_add_sysfs(struct hci_conn > > static void del_conn(struct work_struct *work) > > { > > struct hci_conn *conn = container_of(work, struct hci_conn, work); > > + get_device(&conn->dev); > > device_del(&conn->dev); > > + put_device(&conn->dev); > > } > > > > void hci_conn_del_sysfs(struct hci_conn *conn) > > > > Hi greg, > > BTW, Is it a possible bug of driver core or kobject ? > In device_del if(parent) klist_del() will drop the kref of device and then in bus_remove_device klist_del() will drop it again, so the device would be released. then the following works will oops. So might my patch is a wrong fix. how about the below one: Signed-off-by: Dave Young <[EMAIL PROTECTED]> --- drivers/base/core.c |2 ++ 1 file changed, 2 insertions(+) diff -upr linux/drivers/base/core.c linux.new/drivers/base/core.c --- linux/drivers/base/core.c 2007-12-26 11:00:49.0 +0800 +++ linux.new/drivers/base/core.c 2007-12-26 11:01:18.0 +0800 @@ -926,6 +926,7 @@ void device_del(struct device * dev) struct device * parent = dev->parent; struct class_interface *class_intf; + dev = get_device(dev); if (parent) klist_del(&dev->knode_parent); if (MAJOR(dev->devt)) @@ -966,6 +967,7 @@ void device_del(struct device * dev) cleanup_device_parent(dev); kobject_del(&dev->kobj); put_device(parent); + put_device(dev); } /** -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [BUG][PATCH -mm] bluetooth : rfcomm add get/put device in del_conn
On Dec 25, 2007 6:03 PM, Dave Young <[EMAIL PROTECTED]> wrote: > Due to 2.6.24-rc6-mm1 kernel changes (maybe kobject or driver core), If I > exec: > > rfcomm connect 0 1 > > kernel will oops after connect timeout. > > hand copy some oops text: > > EIP is at driver_sysfs_remove+0x1a/0x40 > Call Trace: > show_trace_log_lvl+0x1a/0x30 > show_stack_log_lvl+0x9a/0xc0 > show_registers+0xc7/0x270 > die+0x129/0x240 > do_page_fault+0x3a1/0x670 > error_code+0x72/0x78 > __device_release_driver+0x1e/0xa0 > device_release_driver+0x30/0x50 > bus_remove_device+0x63/0x90 > device_del+0x55/0x190 > del_conn+0xb/0x10 [bluetooth] > run_workqueue+0xe1/0x210 > worker_thread+0x99/0xf0 > kthread+0x5c/0xa0 > kernel_thread_helper+0x7/0x18 > > (The remote bluetooth device is a mobile phone which is power off) > > The reason is that in bus_remobe_dev, the klist_del function will release the > device, so just add a get/put pair around the device_del in del_conn. > > Signed-off-by: Dave Young <[EMAIL PROTECTED]> > > --- > net/bluetooth/hci_sysfs.c |2 ++ > 1 file changed, 2 insertions(+) > > diff -upr linux/net/bluetooth/hci_sysfs.c linux.new/net/bluetooth/hci_sysfs.c > --- linux/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:09.0 +0800 > +++ linux.new/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:51.0 +0800 > @@ -319,7 +319,9 @@ void hci_conn_add_sysfs(struct hci_conn > static void del_conn(struct work_struct *work) > { > struct hci_conn *conn = container_of(work, struct hci_conn, work); > + get_device(&conn->dev); > device_del(&conn->dev); > + put_device(&conn->dev); > } > > void hci_conn_del_sysfs(struct hci_conn *conn) > Hi greg, BTW, Is it a possible bug of driver core or kobject ? Regards dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[BUG][PATCH -mm] bluetooth : rfcomm add get/put device in del_conn
Due to 2.6.24-rc6-mm1 kernel changes (maybe kobject or driver core), If I exec: rfcomm connect 0 1 kernel will oops after connect timeout. hand copy some oops text: EIP is at driver_sysfs_remove+0x1a/0x40 Call Trace: show_trace_log_lvl+0x1a/0x30 show_stack_log_lvl+0x9a/0xc0 show_registers+0xc7/0x270 die+0x129/0x240 do_page_fault+0x3a1/0x670 error_code+0x72/0x78 __device_release_driver+0x1e/0xa0 device_release_driver+0x30/0x50 bus_remove_device+0x63/0x90 device_del+0x55/0x190 del_conn+0xb/0x10 [bluetooth] run_workqueue+0xe1/0x210 worker_thread+0x99/0xf0 kthread+0x5c/0xa0 kernel_thread_helper+0x7/0x18 (The remote bluetooth device is a mobile phone which is power off) The reason is that in bus_remobe_dev, the klist_del function will release the device, so just add a get/put pair around the device_del in del_conn. Signed-off-by: Dave Young <[EMAIL PROTECTED]> --- net/bluetooth/hci_sysfs.c |2 ++ 1 file changed, 2 insertions(+) diff -upr linux/net/bluetooth/hci_sysfs.c linux.new/net/bluetooth/hci_sysfs.c --- linux/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:09.0 +0800 +++ linux.new/net/bluetooth/hci_sysfs.c 2007-12-25 17:45:51.0 +0800 @@ -319,7 +319,9 @@ void hci_conn_add_sysfs(struct hci_conn static void del_conn(struct work_struct *work) { struct hci_conn *conn = container_of(work, struct hci_conn, work); + get_device(&conn->dev); device_del(&conn->dev); + put_device(&conn->dev); } void hci_conn_del_sysfs(struct hci_conn *conn) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/