Re: [4.1.0-07254-gc13c810] Regression: Bluetooth not working.

2015-06-29 23:13 GMT+02:00 Tedd Ho-Jeong An [off-list ref]:

Hi Jorg

On Mon, 29 Jun 2015 16:37:32 +0200
J=C3=B6rg Otte [off-list ref] wrote:

quoted

2015-06-29 12:30 GMT+02:00 Alexey Dobriyan [off-list ref]:

quoted

On Mon, Jun 29, 2015 at 12:00 PM, J=C3=B6rg Otte [off-list ref] =

wrote:

quoted

quoted

quoted

2015-06-28 18:09 GMT+02:00 Alexey Dobriyan [off-list ref]:

quoted

On Sun, Jun 28, 2015 at 05:36:04PM +0200, J=C3=B6rg Otte wrote:

quoted

2015-06-26 16:28 GMT+02:00 J=C3=B6rg Otte [off-list ref]:

quoted

2015-06-26 12:03 GMT+02:00 J=C3=B6rg Otte [off-list ref]:

quoted

2015-06-26 11:37 GMT+02:00 Marcel Holtmann [off-list ref]=

:

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

Hi Joerg,

quoted

Bluetooth is inoperable in current Linus tree and the
first bad commit is:

835a6a2f8603237a3e6cded5a6765090ecb06ea5 is the first bad comm=

it

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

commit 835a6a2f8603237a3e6cded5a6765090ecb06ea5
Author: Alexey Dobriyan [off-list ref]
Date:   Wed Jun 10 20:28:33 2015 +0300

   Bluetooth: Stop sabotaging list poisoning

   list_del() poisons pointers with special values, no need to=

 overwrite them.

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

   Signed-off-by: Alexey Dobriyan [off-list ref]
   Signed-off-by: Marcel Holtmann [off-list ref]

My BT adapter is an intel 8087:07da
I reverted that commit and this fixed the problem for me.

today we had a patch from Tedd fixing the list initialization i=

n the HIDP code.

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/cor=

e.c

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

index 9070dfd6b4ad..f1a117f8cad2 100644

--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c

@@ -915,6 +915,7 @@ static int hidp_session_new(struct hidp_ses=

sion **out, const bdaddr_t *bdaddr,

quoted

quoted

quoted

quoted

quoted

quoted

quoted

quoted

        session->conn =3D l2cap_conn_get(conn);
        session->user.probe =3D hidp_session_probe;
        session->user.remove =3D hidp_session_remove;
+       INIT_LIST_HEAD(&session->user.list);
        session->ctrl_sock =3D ctrl_sock;
        session->intr_sock =3D intr_sock;
        skb_queue_head_init(&session->ctrl_transmit);

Could this be fixing it for you as well?

I will check this when I am at home in the
afternoon.

The patch works for me too.

Ok, this was a little bit hasty!
I now see the following additional problems:

- System freeze on resume (occures always).
- System freeze on shutdown (occures sometimes)
- System freeze when BT-mouse is connecting (occures sometimes).

Then I can't do anything except power off.

This happens only if Bluetooth AND BT-mouse is activated.

OK, what happens if you just revert only list_del patch?

I have applied this patch:

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 9070dfd6b4ad..f1a117f8cad2 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c

@@ -915,6 +915,7 @@ static int hidp_session_new(struct hidp_session

**out, const bdaddr_t *bdaddr,
        session->conn =3D l2cap_conn_get(conn);
        session->user.probe =3D hidp_session_probe;
        session->user.remove =3D hidp_session_remove;
+       INIT_LIST_HEAD(&session->user.list);
        session->ctrl_sock =3D ctrl_sock;
        session->intr_sock =3D intr_sock;
        skb_queue_head_init(&session->ctrl_transmit);

without this patch bluetooth doesn't work at all for me.

Sure.

Please drop this patch, and do

  git-revert 835a6a2f8603237a3e6cded5a6765090ecb06ea5

Maybe it's some other changes causing hangs.

Looks good so far. The system freeze on resume is gone.

Thanks, J=C3=B6rg

Regarding the system hang issue, it looks like the problem is caused by t=

he list_del().

According to the list.h, this macro puts the entry into invalid state and=

 it causes the device hang in the l2cap_core.c

    /**
     * list_del - deletes entry from list.
     * @entry: the element to delete from the list.
     * Note: list_empty() on entry does not return true after this, the e=

ntry is

     * in an undefined state.
     */

So, one way to fix this issue is using the list_del_init() instead.

Can you try this patch to see if it resolve the issue? No need to revert =

any patch.

I ran a quick test with a different scenarios and it looks good to me so =

far.

 struct l2cap_user *user)

_conn *conn)

        while (!list_empty(&conn->users)) {
                user =3D list_first_entry(&conn->users, struct l2cap_user=

, list);

-               list_del(&user->list);
+               list_del_init(&user->list);
                user->remove(conn, user);
        }
 }

Regards,
Tedd Ho-Jeong An

I now have both patche applied and no revert. Looks good so far.

Thanks, J=C3=B6rg