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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.0 (3.60.0-1.fc44) Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Hi, ke, 2026-04-22 kello 11:09 -0400, Michael Bommarito kirjoitti: > On Wed, Apr 22, 2026 at 10:55=E2=80=AFAM Luiz Augusto von Dentz > wrote: > > We might need a lock in order to access the session->conn: >=20 > This one is a little easier than the other txwin_size issue in terms > of blast radius. >=20 > What pattern would you prefer here? >=20 > Option 1, smaller but ordering questions: hold the semaphore across > check and use like this: >=20 > down_read(&hidp_session_sem); > if (session->conn) > l2cap_unregister_user(session->conn, &session->user); > up_read(&hidp_session_sem) >=20 >=20 > Option 2, more correct but more cycles: snapshot the conn and use outside >=20 > down_read(&hidp_session_sem); > conn =3D session->conn; > if (conn) > l2cap_conn_get(conn); > up_read(&hidp_session_sem); > if (conn) { > l2cap_unregister_user(conn, &session->user); > l2cap_conn_put(conn); > } I'm not sure now (would need to rethink it through), but one probably should check if dbf666e4fc9b is needed or whether 752a6c9596d alone would be enough to address the original issue. --=20 Pauli Virtanen