Re: Bluetooth is very ill in -next

Dave Young
2009-10-02T10:57:40Z

On Wed, Sep 30, 2009 at 02:26:36PM +0100, Alan Cox wrote:
>
> Doing "sdptool search DUN" reliably crashes the kernel when using a USB
> bluetooth dongle
>
> Language Base Attr List:
> code_ISO639: 0x656e
> encoding: 0x6a
> base_offset: 0x100
> Profile Descriptor List:
> "Dialup Networking" (0x1103)
> Version: 0x0100
>
>
> is as far as it gets
>
> It then explodes
>
> _spin_lock_irqsave
> ?skb_dequeue
> skb_dequeue
> skb_queue_purge
> l2cap_recv_frame
> ?__lock_acquire
> ?__usb_hcd_submit_urb
> ?__lock_acquire
> l2cap_recv_acldata
> hci_rx_task
> ?l2cap_recv_acldata
> tasklet_action
>
> reliably.
>

Marcel, please take a look at following patch, same as previous
dev_set_name problem.

---
Due to driver core changes dev_set_drvdata will call kzalloc which should be
in might_sleep context, but hci_conn_add will be called in atomic context

Like dev_set_name just put all other device callbacks to work queue function.

oops as following:

Oct 2 17:41:59 darkstar kernel: [ 438.001341] BUG: sleeping function called from invalid context at mm/slqb.c:1546
Oct 2 17:41:59 darkstar kernel: [ 438.001345] in_atomic(): 1, irqs_disabled(): 0, pid: 2133, name: sdptool
Oct 2 17:41:59 darkstar kernel: [ 438.001348] 2 locks held by sdptool/2133:
Oct 2 17:41:59 darkstar kernel: [ 438.001350] #0: (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.+.}, at: [<faa1d2f5>] lock_sock+0xa/0xc [l2cap]
Oct 2 17:41:59 darkstar kernel: [ 438.001360] #1: (&hdev->lock){+.-.+.}, at: [<faa20e16>] l2cap_sock_connect+0x103/0x26b [l2cap]
Oct 2 17:41:59 darkstar kernel: [ 438.001371] Pid: 2133, comm: sdptool Not tainted 2.6.31-mm1 #2
Oct 2 17:41:59 darkstar kernel: [ 438.001373] Call Trace:
Oct 2 17:41:59 darkstar kernel: [ 438.001381] [<c022433f>] __might_sleep+0xde/0xe5
Oct 2 17:41:59 darkstar kernel: [ 438.001386] [<c0298843>] __kmalloc+0x4a/0x15a
Oct 2 17:41:59 darkstar kernel: [ 438.001392] [<c03f0065>] ? kzalloc+0xb/0xd
Oct 2 17:41:59 darkstar kernel: [ 438.001396] [<c03f0065>] kzalloc+0xb/0xd
Oct 2 17:41:59 darkstar kernel: [ 438.001400] [<c03f04ff>] device_private_init+0x15/0x3d
Oct 2 17:41:59 darkstar kernel: [ 438.001405] [<c03f24c5>] dev_set_drvdata+0x18/0x26
Oct 2 17:41:59 darkstar kernel: [ 438.001414] [<fa51fff7>] hci_conn_init_sysfs+0x40/0xd9 [bluetooth]
Oct 2 17:41:59 darkstar kernel: [ 438.001422] [<fa51cdc0>] ? hci_conn_add+0x128/0x186 [bluetooth]
Oct 2 17:41:59 darkstar kernel: [ 438.001429] [<fa51ce0f>] hci_conn_add+0x177/0x186 [bluetooth]
Oct 2 17:41:59 darkstar kernel: [ 438.001437] [<fa51cf8a>] hci_connect+0x3c/0xfb [bluetooth]
Oct 2 17:41:59 darkstar kernel: [ 438.001442] [<faa20e87>] l2cap_sock_connect+0x174/0x26b [l2cap]
Oct 2 17:41:59 darkstar kernel: [ 438.001448] [<c04c8df5>] sys_connect+0x60/0x7a
Oct 2 17:41:59 darkstar kernel: [ 438.001453] [<c024b703>] ? lock_release_non_nested+0x84/0x1de
Oct 2 17:41:59 darkstar kernel: [ 438.001458] [<c028804b>] ? might_fault+0x47/0x81
Oct 2 17:41:59 darkstar kernel: [ 438.001462] [<c028804b>] ? might_fault+0x47/0x81
Oct 2 17:41:59 darkstar kernel: [ 438.001468] [<c033361f>] ? __copy_from_user_ll+0x11/0xce
Oct 2 17:41:59 darkstar kernel: [ 438.001472] [<c04c9419>] sys_socketcall+0x82/0x17b
Oct 2 17:41:59 darkstar kernel: [ 438.001477] [<c020329d>] syscall_call+0x7/0xb

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
---
net/bluetooth/hci_sysfs.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)

--- linux-2.6.31.orig/net/bluetooth/hci_sysfs.c 2009-10-02 18:04:14.000000000 +0800
+++ linux-2.6.31/net/bluetooth/hci_sysfs.c 2009-10-02 18:05:22.000000000 +0800
@@ -90,6 +90,14 @@ static void add_conn(struct work_struct
struct hci_conn *conn = container_of(work, struct hci_conn, work_add);
struct hci_dev *hdev = conn->hdev;

+ conn->dev.type = &bt_link;
+ conn->dev.class = bt_class;
+ conn->dev.parent = &hdev->dev;
+
+ dev_set_drvdata(&conn->dev, conn);
+
+ device_initialize(&conn->dev);
+
dev_set_name(&conn->dev, "%s:%d", hdev->name, conn->handle);

if (device_add(&conn->dev) < 0) {
@@ -136,18 +144,8 @@ static void del_conn(struct work_struct

void hci_conn_init_sysfs(struct hci_conn *conn)
{
- struct hci_dev *hdev = conn->hdev;
-
BT_DBG("conn %p", conn);

- conn->dev.type = &bt_link;
- conn->dev.class = bt_class;
- conn->dev.parent = &hdev->dev;
-
- dev_set_drvdata(&conn->dev, conn);
-
- device_initialize(&conn->dev);
-
INIT_WORK(&conn->work_add, add_conn);
INIT_WORK(&conn->work_del, del_conn);
}