summaryrefslogtreecommitdiff
path: root/drivers/usb/serial/usb-serial.c
AgeCommit message (Collapse)Author
2009-08-03USB: fix wrong order of events in usb serial suspensionOliver Neukum
if a subdriver has an additional suspend method, it must be called first to allow the subdriver to return -EBUSY, because the second half cannot be easily undone. Signed-off-by: Oliver Neukum <oliver@neukum.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-03USB: usb-serial, remove unused variablesJiri Slaby
There are some unused variables in serial_do_down. Remove them. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-03tty: USB serial termios bitsAlan Cox
Various drivers have hacks to mangle termios structures. This stems from the fact there is no nice setup hook for configuring the termios settings when the port is created Signed-off-by: Alan Cox <alan@linux.intel.com>
2009-08-03tty: USB does not need the filp argument in the driversAlan Cox
And indeed none of them use it. Clean this up as it will make moving to a standard open method rather easier. Signed-off-by: Alan Cox <alan@linux.intel.com>
2009-08-03tty: USB can now use the shutdown method for kref based freeing of portsAlan Cox
Signed-off-by: Alan Cox <alan@linux.intel.com>
2009-08-03tty: USB hangup is racyAlan Cox
The USB layer uses tty_hangup to deal with unplugs of the physical hardware (analogous to loss of carrier) and then frees the resources. However the tty_hangup is asynchronous. As the hangup can sleep we can use tty_vhangup which is the non async version to avoid freeing resources too early. Signed-off-by: Alan Cox <alan@linux.intel.com>
2009-07-27usb_serial: Fix remaining ref count/lock bugsAlan Cox
This fixes - locking bug that was hidden by ecc2e05e739c30870c8e4f252b63a0c4041f2724 - Regression #13821 - Spurious warning when closing and blocking for data write out With these changes my PL2303 always ends up as ttyUSB0 when it should and the module refcounts stay correct. I'll do a more wholesale split & tidy of _open in the next release or two as we get a standard tty_port_open and port->ops->init port->ops->shutdown call backs. Copy sent to Alan Stern and Carlos Mafra just to confirm it fixes all the reports but it passes local testing with the same hardware as Alan Stern. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27tty: Fix a USB serial crash/scribbleAlan Cox
The port lock is used to protect the port state. However the port structure is freed on a hangup, then the lock taken on a close. The right fix is to drop the port on tty->shutdown() but we can't yet do that due to sleep v non-sleeping rules. Instead do the next best thing and fix it up when we are not in -rc season. Reported-by: Daniel Mack <daniel@caiaq.de> Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Daniel Mack <daniel@caiaq.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (48 commits) USB: otg: fix module reinsert issue USB: handle zero-length usbfs submissions correctly USB: EHCI: report actual_length for iso transfers USB: option: remove unnecessary and erroneous code USB: cypress_m8: remove invalid Clear-Halt USB: musb_host: undo incorrect change in musb_advance_schedule() USB: fix LANGID=0 regression USB: serial: sierra driver id_table additions USB serial: Add ID for Turtelizer, an FT2232L-based JTAG/RS-232 adapter. USB: fix race leading to a write after kfree in usbfs USB: Sierra: fix oops upon device close USB: option.c: add A-Link 3GU device id USB: Serial: Add support for Arkham Technology adapters USB: Fix option_ms regression in 2.6.31-rc2 USB: gadget audio: select SND_PCM USB: ftdi: support NDI devices Revert USB: usbfs: deprecate and hide option for !embedded USB: usb.h: fix kernel-doc notation USB: RNDIS gadget, fix issues talking from PXA USB: serial: FTDI with product code FB80 and vendor id 0403 ...
2009-07-12USB: console: Fix regression in usb console on kernel bootJason Wessel
The commit 335f8514f200e63d689113d29cb7253a5c282967 introduced a regression which stopped usb consoles from working correctly as a kernel boot console as well as interactive login device. The addition of the serial_close() which in turn calls tty_port_close_start() will change the reference count of port.count and warn about it. The usb console code had previously incremented the port.count to indicate it was making use of the device as a console and the forced change causes a double open on the usb device which leads to a non obvious kernel oops later on when the tty is freed. To fix the problem instead make use of port->console to track if the port is in fact an active console port to avoid double initialization of the usb serial device. The port.count is incremented and decremented only with in the scope of usb_console_setup() for the purpose of the low level driver initialization. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-12headers: smp_lock.h reduxAlexey Dobriyan
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-25usb_serial: Fix oops when unexisting usb serial device is opened.Thadeu Lima de Souza Cascardo
This commit 335f8514f200e63d689113d29cb7253a5c282967 has stopped properly checking if there is any usb serial associated with the tty in the close function. It happens the close function is called by releasing the terminal right after opening the device fails. As an example, open fails with a non-existing device, when probe has never been called, because the device has never been plugged. This is common in systems with static modules and no udev. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-15USB: usb-serial: replace shutdown with disconnect, releaseAlan Stern
This patch (as1254) splits up the shutdown method of usb_serial_driver into a disconnect and a release method. The problem is that the usb-serial core was calling shutdown during disconnect handling, but drivers didn't expect it to be called until after all the open file references had been closed. The result was an oops when the close method tried to use memory that had been deallocated by shutdown. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15USB: usb-serial: call port_probe and port_remove at the right timesAlan Stern
This patch (as1253) prevents the usb-serial core from calling a driver's port_probe and port_remove methods more than once per port. It also removes some unnecessary try_module_get() calls and adds a missing port_remove method call in a failure path. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-11tty: Bring the usb tty port structure into more useAlan Cox
This allows us to clean stuff up, but is probably also going to cause some app breakage with buggy apps as we now implement proper POSIX behaviour for USB ports matching all the other ports. This does also mean other apps that break on USB will now work properly. Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-28usb-serial: fix crash when sub-driver updates firmwareAlan Stern
This patch (as1244) fixes a crash in usb-serial that occurs when a sub-driver returns a positive value from its attach method, indicating that new firmware was loaded and the device will disconnect and reconnect. The usb-serial core then skips the step of registering the port devices; when the disconnect occurs, the attempt to unregister the ports fails dramatically. This problem shows up with Keyspan devices and it might affect others as well. When the attach method returns a positive value, the patch sets num_ports to 0. This tells usb_serial_disconnect() not to try unregistering any of the ports; instead they are cleaned up by destroy_serial(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-23USB: serial: fix lifetime and locking problemsAlan Stern
This patch (as1229) fixes a few lifetime and locking problems in the usb-serial driver. The main symptom is that an invalid kevent is created when the serial device is unplugged while a connection is active. Ports should be unregistered when device is disconnected, not when the parent usb_serial structure is deallocated. Each open file should hold a reference to the corresponding port structure, and the reference should be released when the file is closed. serial->disc_mutex should be acquired in serial_open(), to resolve the classic race between open and disconnect. serial_close() doesn't need to hold both serial->disc_mutex and port->mutex at the same time. Release the subdriver's module reference only after releasing all the other references, in case one of the release routines needs to invoke some code in the subdriver module. Replace a call to flush_scheduled_work() (which is prone to deadlocks) with cancel_work_sync(). Also, add a call to cancel_work_sync() in the disconnect routine. Reduce the scope of serial->disc_mutex in serial_disconnect(). The only place it really needs to protect is where the "disconnected" flag is set. This fixes the bug reported in http://bugs.freedesktop.org/show_bug.cgi?id=20703 Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Dan Williams <dcbw@redhat.com> Tested-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Oliver Neukum <oliver@neukum.org> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-01proc tty: switch usb-serial to ->proc_fopsAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-24usb-serial: fix usb_serial_register bug when boot with nousb paramDave Young
With "nousb" cmdline booting, built-in serial drivers (ie. airecable) will trigger kernel oops. Indeed, if nousb, usb_serial_init will failed, and the usb serial bus type will not be registerd, then usb_serial_register call driver_register which try to register the driver to a not registered bus. Here add usb_disabled() check in usb_serial_register to fix it. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24USB: serial: refuse to open recently removed USB Serial devicesJames Woodcock
A USB-serial converter device is plugged into a system, and a process opens it's device node. If the device is physically removed whilst the process still has its device node open, then other processes can sucessfully open the now non-existent device's node. I would expect that open() on a device that has been physically removed should return ENODEV. This is manifesting itself with getty on my system. I do the following: 1. set up inittab to spawn getty on ttyUSB0, eg: T1:23:respawn:/sbin/getty -L ttyUSB0 115200 vt100 2. Plug in USB-serial converter cable 3. Wait for a login prompt on a terminal program attached to the serial cable 4. Login 5. Pull the USB-serial converter cable from the box 6. getty doesn't realise that ttyUSB0 no longer exists as /dev/ttyUSB0 can still be opened. 7. Re-insert the USB-serial converter cable 8. You should no longer get a login prompt over the serial cable, as the the USB-serial cable now shows up as /dev/ttyUSB1, and getty is trying to talk to /dev/ttyUSB0. The attached patch will cause open("/dev/ttyUSB0", O_RDONLY) to return ENODEV after the USB-serial converter has been pulled. The patch was created against 2.6.28.1. I can supply it against something else if needs be. It is fairly simple, so should be OK. I am using a pl2303 device, although I don't think that makes any difference. From: James Woodcock <James.Woodcock@ACULAB.COM> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24USB: serial: remove recourse to generic methodOliver Neukum
This removes the fallback to the generic method. It is cleaner to explicitely request it. Introducing this was my mistake. This will be solved by an explicit test and the driver being allowed to request what it needs to be done upon resumption. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24USB: serial: use generic method if no alternative is provided in usb serial ↵Oliver Neukum
layer This patch makes use of the generic method if a serial driver provides no implementation. This simplifies implementing suspend/resume support in serial drivers. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-24USB: serial: introduce a flag into the usb serial layer to tell drivers that ↵Oliver Neukum
their URBs are killed due to suspension This patch introduces a flag into the usb serial layer to tell drivers that their URBs are killed due to suspension. That is necessary to let drivers know whether they should report an error back. Signed-off-by: Oliver Neukum <oneukum@suse.de> Hi Greg, this is for 2.6.30. Patches to use this in drivers are under development. Regards Oliver
2009-01-12usb-serial: remove NULL checkAlan Cox
Julia Lawell found a case where a NULL check was misplaced in the usb-serial code. However as the object in question cannot be NULL the check can simply be removed. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02tty: Drop the lock_kernel in the private ioctl hookAlan Cox
We don't need the BKL here any more so it can go. In a couple of spots the driver requirements are not clear so push the lock down into the driver. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02tty: USB tty devices can block in tcdrain when unpluggedAlan Cox
The underlying problem is that the device methods don't all correctly handle disconnected status and some keep reporting bytes pending which causes tcdrain to stall. When the cable is unplugged they are definitely gone, and as this is true for all USB cables we can fix it in the core usb serial code. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02tty: Fix close races in USB serialAlan Cox
USB serial has always had races where the tty port usage count can hit zero during a receive event. The internal locking is a mutex so we can't use that in the IRQ handlers. With krefs we can tackle this differently but we still need to be careful. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30tty: Fix USB kref leakAlan Cox
When we close we must clear the extra reference we got when we read port->tty. Setting the port tty NULL will clear the kref held by the driver but not the one we obtained ourselves while doing the lookup. Signed-off-by: Alan Cox <alan@redhat.com> Tested-by: Helge Hafting <helge.hafting@aitel.hist.no> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17USB: remove use of err() in drivers/usb/serialGreg Kroah-Hartman
err() is going away, so switch to dev_err() or printk() if it's really needed. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17USB: remove info() macro from usb/serial driversGreg Kroah-Hartman
USB should not be having it's own printk macros, so remove info() and use the system-wide standard of dev_info() wherever possible. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-13tty: usb-serial krefsAlan Cox
Use kref in the USB serial drivers so that we don't free tty structures from under the URB receive handlers as has historically been the case if you were unlucky. This also gives us a framework for general tty drivers to use tty_port objects and refcount. Contains two err->dev_err changes merged together to fix clashes in the -next tree. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-23usb-serial: Add Siemens EF81 to PL-2303 hack triggersAndreas Bombe
This hardware needs the pl2303 hack in order to work properly :( Signed-off-by: Andreas Bombe <aeb@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-13usb-serial: don't release unregistered minorsAlan Stern
This patch (as1121) fixes a bug in the USB serial core. When a device is unregistered, the core will give back its minors -- even if the device hasn't been assigned any! The patch reserves the highest minor value (255) to mean that no minor was assigned. It also removes some dead code and does a small style fixup. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-22tty: rework break handlingAlan Cox
Some hardware needs to do break handling itself and may have partial support only. Make break_ctl return an error code. Add a tty driver flag so you can indicate driver hardware side break support. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22usb-serial: Coding styleAlan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22usb_serial: API all changeAlan Cox
USB serial likes to use port->tty back pointers for the real work it does and to do so without any actual locking. Unfortunately when you consider hangup events, hangup/parallel reopen or even worse hangup followed by parallel close events the tty->port and port->tty pointers are not guaranteed to be the same as port->tty is the active tty while tty->port is the port the tty may or may not still be attached to. So rework the entire API to pass the tty struct. For console cases we need to pass both for now. This shows up multiple drivers that immediately crash with USB console some of which have been fixed in the process. Longer term we need a proper tty as console abstraction Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-21USB: fix usb serial pm counter decrement for disconnected interfacesOliver Neukum
usb serial decrements the pm counter even if an interface has been disconnected. If it was a logical disconnect the interface may belong already to another driver. This patch introduces a check for disconnected interfaces. Signed-off-by: Oliver Neukum <oneukum@suse.de> Cc: Stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21USB: usb-serial: fix a sparse warning about different signednessAndre Haupt
fix the following sparse warning: drivers/usb/serial/usb-serial.c:927:43: warning: incorrect type in argument 3 (different signedness) drivers/usb/serial/usb-serial.c:927:43: expected unsigned int *minor drivers/usb/serial/usb-serial.c:927:43: got int *<noident> CHECK drivers/usb/serial/generic.c Signed-off-by: Andre Haupt <andre@bitwigglers.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21USB: usb dev_set_name() instead of dev->bus_idKay Sievers
The bus_id field is going away, use the dev_set_name() function to set it properly. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21USB: usb dev_name() instead of dev->bus_idKay Sievers
The bus_id field is going away, use the dev_name() function instead. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-30tty: The big operations reworkAlan Cox
- Operations are now a shared const function block as with most other Linux objects - Introduce wrappers for some optional functions to get consistent behaviour - Wrap put_char which used to be patched by the tty layer - Document which functions are needed/optional - Make put_char report success/fail - Cache the driver->ops pointer in the tty as tty->ops - Remove various surplus lock calls we no longer need - Remove proc_write method as noted by Alexey Dobriyan - Introduce some missing sanity checks where certain driver/ldisc combinations would oops as they didn't check needed methods were present [akpm@linux-foundation.org: fix fs/compat_ioctl.c build] [akpm@linux-foundation.org: fix isicom] [akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build] [akpm@linux-foundation.org: fix kgdb] Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-24usb serial: more fixes and groundwork for tty changesAlan Cox
- If a termios change fails due to lack of memory we should copy the old settings back over as the device has not changed - Note various locking problems - kl5kusb105 had various remaining tty flag handling problems - Make safe_serial use tty_insert_flip_string not open coded loops - set termios speed properly in usb_serial Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24USB: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24USB: serial: remove endpoints setting checks from core and headerGreg Kroah-Hartman
Remove the unused check for num_interrupt and friends as well as remove them from the header file because no usb-serial drivers no longer reference them. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24USB: usb-serial: Prepare for BKL push downAlan Cox
Take the lock in usb-serial instead. As it relies on the BKL internally we can't push it any deeper yet. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-15USB: remove broken usb-serial num_endpoints checkGreg Kroah-Hartman
The num_interrupt_in, num_bulk_in, and other checks in the usb-serial code are just wrong, there are too many different devices out there with different numbers of endpoints. We need to just be sticking with the device ids instead of trying to catch this kind of thing. It broke too many different devices. This fixes a large number of usb-serial devices to get them working properly again. Cc: Oliver Neukum <oliver@neukum.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01USB: stop io performed by mos7720 upon close()Oliver Neukum
This fixes a problem where the mos7720 driver will make io to a device from which it has been logically disconnected. It does so by introducing a flag by which the generic usb serial code can signal the subdrivers their disconnection and appropriate locking. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01USB: Prepare serial core for autosuspend.Sarah Sharp
Claim the interface for a USB to serial converter when the tty is open, and release the interface when the tty is closed. If a driver doesn't provide a resume function, use the generic resume instead. Make sure the generic resume function does not submit the URBs if we're coming back from autosuspend. On autoresume, we know that the open function will be called next, which will attempt to submit the URBs. If we submit them in the resume function, the open will fail. This works for: - autosuspend - suspending with the tty open or closed - hibernate with the tty closed A hibernate (or a suspend that causes the USB subsystem to lose power) has issues. If you have the tty open when you hibernate, a new tty will be created when the device re-enumerates during resume. Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01USB: usb_serial: clean tty reference in the last closeAristeu Rozanski
When a usb serial adapter is used as console, the usb serial console driver bumps the open_count on the port struct used but doesn't attach a real tty to it (only a fake one temporaly). If this port is opened later using the regular character device interface, the open method won't initialize the port, which is the expected, and will receive a brand new tty struct created by tty layer, which will be stored in port->tty. When the last close is issued, open_count won't be 0 because of the console usage and the port->tty will still contain the old tty value. This is the last ttyUSB<n> close so the allocated tty will be freed by the tty layer. The usb_serial and usb_serial_port are still in use by the console, so port_free() won't be called (serial_close() -> usb_serial_put() -> destroy_serial() -> port_free()), so the scheduled work (port->work, usb_serial_port_work()) will still run. And usb_serial_port_work() does: (...) tty = port->tty; if (!tty) return; tty_wakeup(tty); which causes (manually copied): Faulting instruction address: 0x6b6b6b68 Oops: Kernel access of bad area, sig: 11 [#1] PREEMPT PowerMac Modules linked in: binfmt_misc ipv6 nfs lockd nfs_acl sunrpc dm_snapshot dm_mirror dm_mod hfsplus uinput ams input_polldev genrtc cpufreq_powersave i2c_powermac therm_adt746x snd_aoa_codec_tas snd_aoa_fabric_layout snd_aoa joydev snd_aoa_i2sbus snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc pmac_zilog serial_core evdev ide_cd cdrom snd appletouch soundcore snd_aoa_soundbus bcm43xx firmware_class usbhid ieee80211softmac ff_memless firewire_ohci firewire_core ieee80211 ieee80211_crypt crc_itu_t sungem sungem_phy uninorth_agp agpart ssb NIP: 6b6b6b68 LR: c01b2108 CTR: 6b6b6b6b REGS: c106de80 TRAP: 0400 Not tainted (2.6.24-rc2) MSR: 40009032 <EE,ME,IR,DR> CR: 82004024 XER: 00000000 TASK = c106b4c0[5] 'events/0' THREAD: c106c000 GPR00: 6b6b6b6b c106df30 c106b4c0 c2d613a0 00009032 00000001 00001a00 00000001 GPR08: 00000008 00000000 00000000 c106c000 42004028 00000000 016ffbe0 0171a724 GPR16: 016ffcf4 00240e24 00240e70 016fee68 016ff9a4 c03046c4 c0327f50 c03046fc GPR24: c106b6b9 c106b4c0 c101d610 c106c000 c02160fc c1eac1dc c2d613ac c2d613a0 NIP [6b6b6b68] 0x6b6b6b68 LR [c01b2108] tty_wakeup+0x6c/0x9c Call Trace: [c106df30] [c01b20e8] tty_wakeup+0x4c/0x9c (unreliable) [c106df40] [c0216138] usb_serial_port_work+0x3c/0x78 [c106df50] [c00432e8] run_workqueue+0xc4/0x15c [c106df90] [c0043798] worker_thread+0xa0/0x124 [c106dfd0] [c0048224] kthread+0x48/0x84 [c106dff0] [c00129bc] kernel_thread+0x44/0x60 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX Slab corruption: size-2048 start=c2d613a0, len=2048 Redzone: 0x9f911029d74e35b/0x9f911029d74e35b. Last user: [<c01b16d8>](release_one_tty+0xbc/0xf4) 050: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b Prev obj: start=c2d60b88, len=2048 Redzone: 0x9f911029d74e35b/0x9f911029d74e35b. Last user: [<c00f30ec>](show_stat+0x410/0x428) 000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b This patch avoids this, clearing port->tty considering if the port is used as serial console or not Signed-off-by: Aristeu Rozanski <arozansk@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-25USB: usb_serial_resume bug fixSarah Sharp
Avoid potential null pointer dereference. Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>