Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754157AbZIGRu2 (ORCPT ); Mon, 7 Sep 2009 13:50:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754122AbZIGRu1 (ORCPT ); Mon, 7 Sep 2009 13:50:27 -0400 Received: from fxip-0047f.externet.hu ([88.209.222.127]:37334 "EHLO pomaz-ex.szeredi.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754101AbZIGRu0 (ORCPT ); Mon, 7 Sep 2009 13:50:26 -0400 To: stern@rowland.harvard.edu CC: miklos@szeredi.hu, alan@linux.intel.com, gregkh@suse.de, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org In-reply-to: (message from Alan Stern on Mon, 7 Sep 2009 11:08:25 -0400 (EDT)) Subject: Re: WARNINGs in usb-serial.c References: Message-Id: From: Miklos Szeredi Date: Mon, 07 Sep 2009 19:50:22 +0200 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9736 Lines: 169 On Mon, 7 Sep 2009, Alan Stern wrote: > On Mon, 7 Sep 2009, Miklos Szeredi wrote: > > > Here's a reproducible Oops on that kernel when trying to connect with > > wvdial. This is a regression compared to -linus, where wvdial works > > (most of the time anyway). > > > > I can bisect it if it's not immediately obvious what is happening... > > I don't think bisecting will help (or is even possible). > > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 > > IP: [] serial_chars_in_buffer+0x47/0x5f [usbserial] > > It's difficult to say without an assembly listing, but I gather that > serial_chars_in_buffer() is seeing port->serial == NULL. Can you > verify this? Yes, that is the case. > This is unexpected, because port->serial is initialized in > usb_serial_probe() and is not set to NULL until destroy_serial(), after > which port should not be used at all. Can you add a > > #define DEBUG > > line at the start of usb-serial.c (before the #include lines) so that > we can tell if destroy_serial() is getting called too early? When you > do, post the dmesg log showing everything from the time you start > running your test. drivers/usb/serial/usb-serial.c: serial_install drivers/usb/serial/usb-serial.c: serial_open - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x541e drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5402 drivers/usb/serial/usb-serial.c: serial_set_termios - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5402 drivers/usb/serial/usb-serial.c: serial_set_termios - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_tiocmget - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5402 drivers/usb/serial/usb-serial.c: serial_set_termios - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 5 byte(s) drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 4 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 13 byte(s) drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 drivers/usb/serial/usb-serial.c: serial_write - port 0, 28 byte(s) drivers/usb/serial/usb-serial.c: serial_write - port 0, 1 byte(s) drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: usb_serial_port_work - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_write_room - port 0 PPP generic driver version 2.4.2 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_open - port 0 drivers/usb/serial/usb-serial.c: serial_tiocmset - port 0 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5401 drivers/usb/serial/usb-serial.c: serial_ioctl - port 0, cmd 0x5404 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 drivers/usb/serial/usb-serial.c: serial_set_termios - port 0 drivers/usb/serial/usb-serial.c: serial_open - port 0 drivers/usb/serial/usb-serial.c: destroy_serial - GSM modem (1-port) drivers/usb/serial/usb-serial.c: return_serial drivers/usb/serial/usb-serial.c: serial_close - port 0 drivers/usb/serial/usb-serial.c: serial_chars_in_buffer = port 0 BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: [] serial_chars_in_buffer+0x47/0x5f [usbserial] PGD 0 Oops: 0000 [#1] PREEMPT SMP last sysfs file: /sys/class/rfkill/rfkill2/state CPU 0 Modules linked in: ppp_generic slhc usb_storage option usbserial bnep sco rfcomm l2cap acpi_cpufreq nf_conntrack_netbios_ns microcode fuse iwl3945 iwlcore mac80211 thinkpad_acpi backlight btusb ac led_class nsc_ircc bluetooth cfg80211 button battery processor thermal irda uinput rfkill e1000e crc_ccitt Pid: 5139, comm: pppd Not tainted 2.6.31-rc8-gkh-00038-g37d0892-dirty #42 2007FUG RIP: 0010:[] [] serial_chars_in_buffer+0x47/0x5f [usbserial] RSP: 0018:ffff88009cc17d78 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8800b5d7a800 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88009cc17ca7 RBP: ffff88009cc17d88 R08: 0000000000000082 R09: ffffffff8105d685 R10: 0000000000000082 R11: 0000000000018600 R12: ffff8800b64af000 R13: ffff8800b64af000 R14: ffff8800b64af000 R15: ffff8800b64af000 FS: 00007ff05244d6f0(0000) GS:ffff880001f45000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000018 CR3: 000000009cc95000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process pppd (pid: 5139, threadinfo ffff88009cc16000, task ffff8800a89f4040) Stack: ffff8800a547c940 7fffffffffffffff ffff88009cc17d98 ffffffff811c7aa2 <0> ffff88009cc17e08 ffffffff811c7ff7 ffff88009cc17df8 0000000000000046 <0> ffff8800a89f4040 ffffffff810c9f8a ffff8800aa902200 ffff8800bf840bc0 Call Trace: [] tty_chars_in_buffer+0x1a/0x1c [] tty_wait_until_sent+0x32/0xfc [] ? kmem_cache_free+0x118/0x18b [] tty_ioctl+0xa6/0x891 [] vfs_ioctl+0x2f/0x7d [] do_vfs_ioctl+0x4af/0x4ec [] ? fget+0x0/0x127 [] ? sysret_check+0x27/0x62 [] sys_ioctl+0x47/0x6a [] system_call_fastpath+0x16/0x1b Code: 00 74 23 0f b6 8b 50 02 00 00 48 c7 c2 20 dc 1c a0 48 c7 c6 67 e0 1c a0 48 c7 c7 87 e0 1c a0 31 c0 e8 93 76 15 e1 48 8b 13 31 c0 42 18 01 75 0d 48 8b 42 08 4c 89 e7 ff 90 58 01 00 00 5b 41 RIP [] serial_chars_in_buffer+0x47/0x5f [usbserial] RSP CR2: 0000000000000018 ---[ end trace ef2106e42e2196ab ]--- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/