Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S977182AbdDXTTN (ORCPT ); Mon, 24 Apr 2017 15:19:13 -0400 Received: from mail.andi.de1.cc ([85.214.239.24]:42815 "EHLO h2641619.stratoserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S976034AbdDXTTE (ORCPT ); Mon, 24 Apr 2017 15:19:04 -0400 From: Andreas Kemnade To: davem@davemloft.net, joe@perches.com, peter@hurleysoftware.com, linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Discussions about the Letux Kernel Cc: Andreas Kemnade Subject: [PATCH] net: hso: fix module unloading Date: Mon, 24 Apr 2017 21:18:39 +0200 Message-Id: <1493061519-15785-1-git-send-email-andreas@kemnade.info> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5469 Lines: 78 keep tty driver until usb driver is unregistered rmmod hso produces traces like this without that: [40261.645904] usb 2-2: new high-speed USB device number 2 using ehci-omap [40261.854644] usb 2-2: New USB device found, idVendor=0af0, idProduct=8800 [40261.862609] usb 2-2: New USB device strings: Mfr=3, Product=2, SerialNumber=0 [40261.872772] usb 2-2: Product: Globetrotter HSUPA Modem [40261.880279] usb 2-2: Manufacturer: Option N.V. [40262.021270] hso 2-2:1.5: Not our interface [40265.556945] hso: unloaded [40265.559875] usbcore: deregistering interface driver hso [40265.595947] Unable to handle kernel NULL pointer dereference at virtual address 00000033 [40265.604522] pgd = ecb14000 [40265.611877] [00000033] *pgd=00000000 [40265.617034] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [40265.622650] Modules linked in: hso(-) bnep bluetooth ipv6 arc4 twl4030_madc_hwmon wl18xx wlcore mac80211 cfg80211 snd_soc_simple_card snd_soc_simple_card_utils snd_soc_omap_twl4030 snd_soc_gtm601 generic_adc_battery extcon_gpio omap3_isp videobuf2_dma_contig videobuf2_memops wlcore_sdio videobuf2_v4l2 videobuf2_core ov9650 bmp280_i2c v4l2_common bmp280 bmg160_i2c bmg160_core at24 nvmem_core videodev bmc150_accel_i2c bmc150_magn_i2c media bmc150_accel_core tsc2007 bmc150_magn leds_tca6507 bno055 snd_soc_omap_mcbsp industrialio_triggered_buffer snd_soc_omap kfifo_buf snd_pcm_dmaengine gpio_twl4030 snd_soc_twl4030 twl4030_vibra twl4030_madc wwan_on_off ehci_omap pwm_bl pwm_omap_dmtimer panel_tpo_td028ttec1 encoder_opa362 connector_analog_tv omapdrm drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect [40265.698211] sysimgblt fb_sys_fops cfbcopyarea drm omapdss usb_f_ecm g_ether usb_f_rndis u_ether libcomposite configfs omap2430 phy_twl4030_usb musb_hdrc twl4030_charger industrialio w2sg0004 twl4030_pwrbutton bq27xxx_battery w1_bq27000 omap_hdq [last unloaded: hso] [40265.723175] CPU: 0 PID: 2701 Comm: rmmod Not tainted 4.11.0-rc6-letux+ #6 [40265.730346] Hardware name: Generic OMAP36xx (Flattened Device Tree) [40265.736938] task: ecb81100 task.stack: ecb82000 [40265.741729] PC is at cdev_del+0xc/0x2c [40265.745666] LR is at tty_unregister_device+0x40/0x50 [40265.750915] pc : [] lr : [] psr: 600b0113 sp : ecb83ea8 ip : eca4f898 fp : 00000000 [40265.763000] r10: 00000000 r9 : 00000000 r8 : 00000001 [40265.768493] r7 : eca4f800 r6 : 00000003 r5 : 00000000 r4 : ffffffff [40265.775360] r3 : c1458d54 r2 : 00000000 r1 : 00000004 r0 : ffffffff [40265.782257] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none [40265.789764] Control: 10c5387d Table: acb14019 DAC: 00000051 [40265.795806] Process rmmod (pid: 2701, stack limit = 0xecb82218) [40265.802062] Stack: (0xecb83ea8 to 0xecb84000) [40265.806640] 3ea0: ec9e8100 c04b3ecc bf737378 ed5b7c00 00000003 bf7327ec [40265.815277] 3ec0: eca4f800 00000000 ec9fd800 eca4f800 bf737070 bf7328bc eca4f820 c05a9a04 [40265.823883] 3ee0: eca4f820 00000000 00000001 eca4f820 ec9fd870 bf737070 eca4f854 ec9fd8a4 [40265.832519] 3f00: ecb82000 00000000 00000000 c04e6960 eca4f820 bf737070 bf737048 00000081 [40265.841125] 3f20: c01071e4 c04e6a60 ecb81100 bf737070 bf737070 c04e5d94 bf737020 c05a8f88 [40265.849731] 3f40: bf737100 00000800 7f5fa254 00000081 c01071e4 c01c4afc 00000000 006f7368 [40265.858367] 3f60: ecb815f4 00000000 c0cac9c4 c01071e4 ecb82000 00000000 00000000 c01512f4 [40265.866973] 3f80: ed5b3200 c01071e4 7f5fa220 7f5fa220 bea78ec9 0010711c 7f5fa220 7f5fa220 [40265.875579] 3fa0: bea78ec9 c0107040 7f5fa220 7f5fa220 7f5fa254 00000800 dd35b800 dd35b800 [40265.884216] 3fc0: 7f5fa220 7f5fa220 bea78ec9 00000081 bea78dcc 00000000 bea78bd8 00000000 [40265.892822] 3fe0: b6f70521 bea78b6c 7f5dd613 b6f70526 80070030 7f5fa254 ffffffff ffffffff [40265.901458] [] (cdev_del) from [] (tty_unregister_device+0x40/0x50) [40265.909942] [] (tty_unregister_device) from [] (hso_free_interface+0x80/0x144 [hso]) [40265.919982] [] (hso_free_interface [hso]) from [] (hso_disconnect+0xc/0x18 [hso]) [40265.929718] [] (hso_disconnect [hso]) from [] (usb_unbind_interface+0x84/0x200) [40265.939239] [] (usb_unbind_interface) from [] (device_release_driver_internal+0x138/0x1cc) [40265.949798] [] (device_release_driver_internal) from [] (driver_detach+0x60/0x6c) [40265.959503] [] (driver_detach) from [] (bus_remove_driver+0x64/0x8c) [40265.968017] [] (bus_remove_driver) from [] (usb_deregister+0x5c/0xb8) [40265.976654] [] (usb_deregister) from [] (SyS_delete_module+0x160/0x1dc) [40265.985443] [] (SyS_delete_module) from [] (ret_fast_syscall+0x0/0x1c) [40265.994171] Code: c1458d54 e59f3020 e92d4010 e1a04000 (e5941034) [40266.016693] ---[ end trace 9d5ac43c7e41075c ]--- Signed-off-by: Andreas Kemnade --- drivers/net/usb/hso.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c index 2e66340..b75e23f 100644 --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -3293,9 +3293,9 @@ static void __exit hso_exit(void) pr_info("unloaded\n"); tty_unregister_driver(tty_drv); - put_tty_driver(tty_drv); /* deregister the usb driver */ usb_deregister(&hso_driver); + put_tty_driver(tty_drv); } /* Module definitions */ -- 2.1.4