Hi Johan/Kuba, On Fri, Oct 23, 2015 at 2:03 PM, Johan Hedberg <johan.hedberg@xxxxxxxxx> wrote: > Hi Syam, > > On Fri, Oct 23, 2015, s.syam@xxxxxxxxxxx wrote: >> We have observed one kernel panic during the sco close. >> The panic logs has been given below. Further analysis we could see that invalid memory access is happening at >> sco_pi(sk)->conn->hcon = NULL; in __sco_sock_close(). >> >> It will be great if someone analyses and provide the fix/clue for this issue. >> Thanks for your time. >> >> >> Code: >> static void __sco_sock_close(struct sock *sk) >> { >> BT_DBG("sk %p state %d socket %p", sk, sk->sk_state, sk->sk_socket); >> >> switch (sk->sk_state) { >> case BT_LISTEN: >> sco_sock_cleanup_listen(sk); >> break; >> >> case BT_CONNECTED: >> case BT_CONFIG: >> if (sco_pi(sk)->conn->hcon) { >> sk->sk_state = BT_DISCONN; >> sco_sock_set_timer(sk, SCO_DISCONN_TIMEOUT); >> hci_conn_drop(sco_pi(sk)->conn->hcon); >> sco_pi(sk)->conn->hcon = NULL; //Invalid memory access happen here. >> } else >> sco_chan_del(sk, ECONNRESET); >> break; >> >> case BT_CONNECT2: >> case BT_CONNECT: >> case BT_DISCONN: >> ... >> ... >> } >> } >> >> Logs: >> Oct 21 23:35:12 alert Kernel: [ 175.323507] Unable to handle kernel NULL pointer dereference at virtual address 00000000 >> ..... >> Oct 21 23:35:12 warn Kernel: [ 175.338344] [<c0866be4>] (__sco_sock_close+0x1ec/0x230) from [<c0866d20>] (sco_sock_close+0x20/0x34) >> Oct 21 23:35:12 warn Kernel: [ 175.338478] [<c0866d20>] (sco_sock_close+0x20/0x34) from [<c0866d78>] (sco_sock_release+0x44/0x100) >> Oct 21 23:35:12 warn Kernel: [ 175.338614] [<c0866d78>] (sco_sock_release+0x44/0x100) from [<c0721ad0>] (sock_release+0x20/0xc4) >> Oct 21 23:35:12 warn Kernel: [ 175.338745] [<c0721ad0>] (sock_release+0x20/0xc4) from [<c07221e4>] (sock_close+0x20/0x2c) >> Oct 21 23:35:12 warn Kernel: [ 175.338874] [<c07221e4>] (sock_close+0x20/0x2c) from [<c02741d0>] (fput+0x11c/0x230) >> Oct 21 23:35:12 warn Kernel: [ 175.338994] [<c02741d0>] (fput+0x11c/0x230) from [<c0270fa8>] (filp_close+0x70/0x7c) >> Oct 21 23:35:12 warn Kernel: [ 175.339110] [<c0270fa8>] (filp_close+0x70/0x7c) from [<c0271064>] (sys_close+0xb0/0xf0) >> Oct 21 23:35:12 warn Kernel: [ 175.339232] [<c0271064>] (sys_close+0xb0/0xf0) from [<c0105d9c>] (__sys_trace_return+0x0/0x24) > > You'll probably want to take a look at the SCO socket patch set that > Kuba sent in the beginning of this month: > > [PATCH 0/5] Few proposed fixes to stop crashes on fast SCO disconnec > > Particularly his second patch looks like something that could be related > to this. > Thanks for your guidance. We will try with Kuba's patch sets. Few of them has already applied to bluetooth-next a couple of hours back. Look like his Patch 1/5 fixes the one time issue which I reported 3 months back with subject "Sco connection disconnection panic happen". Thanks Johan & Kuba. Regards, Syam. -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html